debaira

Quick Firefox 3.5 Installation Guide

2009-07-03T06:02:00.000-07:00

10 simple steps to install Firefox 3.5 on your Linux PC

1. Download the Firefox 3.5 from here

For example, on my Linux PC, I have downloaded Firefox 3.5 (firefox-3.5.tar.bz2) in my Download folder:

[rakesh@debian Download]$ ls
firefox-3.5.tar.bz2

2. Make a folder (e.g. for me, install) in your home

[rakesh@debian ~]$ mkdir install

3. Move firefox-3.5.tar.bz2 from your gnome Desktop or Download folder to install folder (the folder where you have downloaded firefox-3.5.tar.bz2 file)

[rakesh@debian ~]$ mv /home/rakesh/Download/firefox-3.5.tar.bz2 install/

4. Goto the install folder

[rakesh@debian ~]$ cd install/
[rakesh@debian install]$ ls
firefox-3.5.tar.bz2

5. Extract firefox-3.5.tar.bz2 file

[rakesh@debian install]$ tar -xvf firefox-3.5.tar.bz2
firefox/
firefox/update.locale
firefox/plugins/
firefox/plugins/libnullplugin.so
firefox/Throbber-small.gif
firefox/components/
firefox/components/nsSessionStore.js
firefox/components/nsFilePicker.js
..........
.....

6. Goto firefox folder

[rakesh@debian ]$ cd firefox
[rakesh@debian firefox]$ pwd
/home/rakesh/install/firefox

7. Make a symbolic link to launch Firefox 3.5

[rakesh@debian firefox]$ ln -s /home/rakesh/install/firefox/firefox ~/Desktop/Firefox3.5

8. Make it (Firefox 3.5) executable

[rakesh@debian firefox]$ chmod +x ~/Desktop/Firefox3.5

To open Firefox, from the command line you would type: firefox &

[rakesh@debian firefox]$ firefox &

If steps 7 and 8 do not work for you then follow an alternative option at step 9

9. Goto your gnome Desktop and

a) Right click on the gnome Desktop and
b) select the Create Launcher... option
c) click the button labeled Basic
d) type in "Name:" field : Firefox 3.5
e) type in "Command:" field: /home/rakesh/install/firefox/firefox
f) type in "Comment:" field: Firefox 3.5
g) now click Close button

10. You will see a Firfox 3.5 logo on your Desktop and just click the logo to launch Firefox 3.5 and browser the web.

Enjoy Firefox 3.5 ... :)

Todo.txt CLI Manages Your Tasks from the Command Line

2009-07-01T23:08:00.000-07:00

Dozens of fancy point-and-click task managers promise to organize your to-do list, but so often power users find that nothing outdoes that trusty old classic: the todo.txt file.

If you're a command line lover who skips checkboxes and drop-downs to dash off notes and tasks in a regular old text file, or you're intrigued by the idea and wish your todo.txt chops were stronger, read on.

Gina has been a heavy todo.txt user for years. Back in 2006, he started developing a command line interface (CLI) to my todo.txt which lets him add to and check off items without launching a full-on text editor. Three years of daily (or at least weekly) use later, version 2.0 of the script is now available. It offers basic to advanced commands for managing your todo.txt and other text files you might use to capture information, like ideas.txt or maybelater.txt. Let's take a look.

Who This Is Meant For: If you're comfortable working in the terminal, changing permissions on a file, and working with Unix-style text commands, then the todo.txt CLI is for you. If you don't spend a good amount of time at the command line—either in the Terminal on your Mac, or using a Unix command line or emulator on Windows—you're going to think this whole thing is arcane and confusing. (In that case, we highly recommend getting organized with Remember the Milk. If you want to boost your command line chops on Windows, check out our introduction to Cygwin.)

You've already got CLI religion? Good. Let's get started on some hot todo.txt command line action.

Quick Start Guide:

Download the Todo.txt CLI 2.0 zip file and extract it. You'll get two files. Place both todo.cfg (the configuration file) and todo.sh in your home directory.
Open the todo.cfg file with your text editor of choice. Set the TODO_DIR variable to the right path for your setup. For example, on my Linux PC, this line reads:
TODO_DIR="/home/[your home directory name]/todo"
On Windows PC, this line reads:
TODO_DIR="C:/Documents and Settings/gina/My Documents"
On my Mac, this line reads:
TODO_DIR="/Users/gina/Documents/todo"
Make the todo.sh file executable by using the command: chmod +x todo.sh
(OPTIONAL) Alias the letter t to todo.sh to save keystrokes while you use it. In your ~/.bash_profile file, add the line:
alias t='~/todo.sh'

Now you're ready to put this script to work!

Basic Usage

Before we start, keep in mind that this CLI isn't trying to reinvent the text editor. If you want to do big bulk edits to a lot of items in your todo.txt, just open it up in your favorite text editor to do so. But for quick, one-hit access to add items, mark items as complete, or slice and dice your list by project or priority, todo.sh is for you.

For example, to add a line to your todo.txt file, at the command line, type:

$ t add "Pick up milk"

Add a few more items for good measure:

$ t add "Pick up the dry cleaning"
$ t add "Clean out the inbox"

Now, to see all the items on your list, use:

$ t ls

The output will look like this:

$ t ls 03 Clean out the inbox 01 Pick up milk 02 Pick up the dry cleaning -- TODO: 3 tasks in C:/Documents and Settings/gina/My Documents/todo.txt.

Now, you can reference each item by its ID—which is actually the line number it lives at in the todo.txt file. For instance, to prioritize task 1 to the highest level—priority A—use this command:

$ t pri 1 A

To mark task 2 as complete, use todo.sh's do action:

$ t do 2

Since a video is worth a million words, see this in action in this screencast demonstration of a to-do list you might find for a crew member on Battlestar Galactica. (Go full-screen to see what's being typed more clearly.)

If this video clip isn't clear enough for you, try this alternate high-res location.

Advanced Usage

Once you've got the basics of working with your todo.txt down, it's time to dive into more advanced tricks. Here are a few more things this CLI can do.

Replace or delete a task; append or prepend text to a line. When you want to re-word a task or add a context, project, or additional info to it, use the replace, append, and prepend actions to do so. For example, add "ready at 3PM" to your "Pick up the dry cleaning task" with this command:
$ t append 2 "ready at 3PM"
See all the contexts and projects in your list. If you're using the + and @ sign format to signify projects and contexts, use the listcon and listproj (or lsc and lsprj for short) commands to see a short list of all your contexts or projects in your todo.txt.
Move items from your todo.txt to another text file. Say you've decided that the "Learn how to speak French" task is actually something you're not quite committed to doing—yet. Use todo.sh's mv command to zip that task from todo.txt to another text file in your todo directory. For example, this command will move it into a maybelater.txt file:
$ t move 10 maybelater.txt
List the contents of another text file. Since I got so used to working with todo.txt this way, there's now support for working with other text files. For example, you can list the contents of your maybelater.txt file using the command:
$ t listfile maybelater.txt

Likewise, you can add a line to another file using:

$ t addto ideas.txt "My bright idea"

You can also search the contents of another text file by adding a keyword after the list command, ala:

$ t lf ideas.txt apple

See all the options available to you using the todo.sh -h command. The full usage manual is available here.

Five Game-Changing Features in Firefox 3.5

2009-05-24T01:09:00.000-07:00

The latest Firefox may still be in beta but it boasts a number of behind-the-scenes features that will make developing for the web easier as well as end-user changes that add new functionality, like private browsing and support for drag and drop.

Firefox 3.5 is coming very soon, and this release includes a number of features that up the ante for Web browsers and the Web as an application platform. Some of the game-changing features in Firefox 3.5 won’t be immediately visible to end-users, but they’ll allow Web developers to build Web applications that make the Web even more fun and useful than it already is. Let’s take a look at five of the prominent features you can test drive today in Firefox 3.5.

You can grab tarballs from Mozilla the Mozilla beta announcement page, though many Linux distros also have testing packages available as add-on repositories. For instance, openSUSE users can add the mozilla:beta repository to track the latest Firefox development packages. This gives the added advantage of allowing you to track updates via your distro’s update process, but does mean that updates will usually lag a few days behind the official Moz builds.

Because it’s beta software, the standard disclaimers apply: While Firefox betas are pretty stable, you can expect that it will have some bugs and might even do unexpected things like eating your data. I’ve never had this happen, but take reasonable precautions before running the beta — like backing up your profile directory.

Audio and Video Support in Firefox

Ever get sick of worrying about plugins and helper applications to enjoy multimedia content online? Firefox 3.5 may be the beginning of the end for that particular hassle with support for HTML 5 audio and video elements, and support for the Ogg and WAV formats in the browser itself.

The audio and video elements make it easier to add video and audio to Web pages, with a few lines of HTML Take this example from the Firefox developer site:

Your browser does not support the video element.

If you’re using a supported browser like Firefox 3.5, you’ll see test bars just like we used to enjoy at the end of the broadcast day on television. (Remember when the broadcast day actually ended?) If not, you should just see: “Your browser does not support the video element.”

As a side note, Firefox’s inclusion of Ogg might just help make the free but not yet mainstream format break through. This would be a big win for Linux users who have excellent tools for encoding and decoding Ogg but not a lot of mainstream content in Ogg to view or listen to. Labels like Magnatune that support Ogg out of the box are few and far between.

If you’re running Firefox 3.5, you can catch a number of sample videos on TinyVid.

Private Browsing

Over the years, Firefox has added a number of features that make it easier to erase your browsing tracks — so if you’re sharing a computer with others, you can erase history, cookies, cache and other bits that would let snoopers see how you spend your browsing time. Unfortunately, it’s a bit of a shotgun approach — meaning you lose history and so forth from all the sites you visit, and not just the ones you want to keep private.

The 3.5 release will take care of this problem by introducing Private Browsing, or what’s more often referred to as “Porn Mode” for Mozilla. Of course, it has much more work safe applications as well. If you’re doing gift shopping, for example, it’s sort of a dead giveaway if your significant other stumbles on your shopping history. For the ~~paranoid~~ security conscious, it’s also a good feature for logging into banking sites or any other type of Web site that displays a lot of private data. Whatever the reason, Firefox’s Private Browsing mode is much more convenient for users than just deleting history at random intervals.

Using Private Browsing, you can start up a Firefox session that doesn’t record cookies, history, etc., so that there’s no trace of your session. When you finish, all of your previous settings and history are untouched, so you lose nothing — unlike the “Clear History” tool in older versions, which clobbers all cookies, etc.

Firefox 3.5 also has added more finely grained options to the Clear History tool. Instead of an “all or nothing” approach, you can get rid of the last hour, two hours, four hours, day, or entire history.

Offline Application Support

Being dependent on a Web application is a bit of a problem when you’re offline. Firefox 3.5 tries to remedy this a bit by adding support for the HTML 5 specs for caching resources for Web apps.

Offline application support isn’t entirely new, Firefox shipped bits of this with Firefox 3.0 and add-ons like Google Gears have provided offline support for Gears-enabled Web apps. However, Firefox 3.5 fully supports the HTML 5 specification for offline application support — which ought to give a boost to offline Web apps, beyond Google Gears.

Drag and Drop

Typically, Web applications lack the same feature functionality that desktop applications do. Case in point: Drag and drop between applications. Sure, you can copy and paste some things between browser windows and different Web sites, but drag and drop capabilities are seriously limited compared to desktop applications.

Firefox 3.5 beefs up the abilities to drag and drop data types between applications and even multiple items. It may seem like a minor feature, but it gives Web apps the ability to work more like desktop applications, which is another hurdle for those who’d like to see Web applications replace fat apps.

Geolocation

Geolocation seems to be all the rage these days — services like Google Latitude allow users to report their location via the computer or mobile phone so your friends and stalkers can track your location more conveniently. Ecommerce sites can pick up your location to suggest nearby stores, and so forth.

I’m not entirely sure this is a desirable feature, but a lot of users seem to want it — and Firefox 3.5 gives developers and users the tools to make it possible beyond services like Latitude. If you’re totally freaked out by the prospect of Web sites knowing your location, it can be turned off.

Basically, service providers can report your location based on wireless access points and IP address. Depending where you are in the world, this can be very accurate (within a few meters, which is pretty darn specific) or wildly inaccurate. With your permission, Firefox can then report the location to Web sites that request it.

My experience with the technology so far is that it’s good at getting within the general city/county, but beyond that not so much. But the technology is only going to get better (especially with mobile devices that have GPS) and more widely used.

All in all, Firefox 3.5 has a lot of new functionality that’s going to be really useful regardless whether you’re a Web developer or an end-users.

Free Linux Ebooks Collection For Newbie

2009-05-13T21:39:00.000-07:00

I'm listing here a free book collection and sure it will very useful among Linux users and rightfully so, who doesn’t like free books? No matter how experienced you are with Linux systems, there is always something new you can learn from a good book that focuses on specific aspects of a Linux system. I tried to make a list of free books by categories. “Beginners”, “Advanced” and “Administrators”.

Here I have listed e-Books for "Linux Ebooks For Newbie", "Intermediate and Advanced Linux Users" and "Linux System Administrators".

Here's listed a comprehensive list of Free Linux related e-books. I didn't arrange the ebooks in proper categories.

E-books:

Free Linux Ebooks For Newbie:

1. Ubuntu Pocket Guide and Reference

Author: Keir Thomas
Format: PDF

2. Linux Newbie Administrator Guide

Author: Peter and Stan Klimas
Format: HTML

3. Introduction to Linux - A Hands on Guide

Author: Machtelt Garrels
Format: HTML

4. Bash Guide for Beginners

Author: Machtelt Garrels
Format: HTML

5. Rute User’s Tutorial and Exposition

Author: Paul Sheer
Format: HTML

6. The Linux Starter Pack

Author: Paul Hudson
Format: PDF

7. FLOSS Manuals

Author: FSF
Format: HTML & PDF

8. The Easiest Linux Guide You’ll Ever Read

Author: Scott Morris
Format: PDF

9. Linux Knowledge Base and Tutorial

Author: James Mohr
Format: PDF

10. Slackware Linux Basics

Author: Daniël de Kok
Format: HTML

How to make OpenOffice load faster

2009-05-10T09:04:00.000-07:00

Here we will discuss the procedure to be followed for making OpenOffice run faster in Ubuntu.

Some simple steps make OpenOffice snappier.

Go to Applications > Office > OpenOffice.org Word Processor

The OpenOffice.org Word Processor is launched. Go to the Tools menu and select Options.

The Options window is opened.
Highlight Memory on the left panel, change the setting as shown below.

Reduce the number of Undo steps to a figure lower than 100. Adelstein suggests 20 or 30 steps.
Under Graphics cache, set Use for OpenOffice.org to 128 MB (up from the original 6MB).
Set Memory per object to 20MB (up from the default .5MB).
Set the number of objects under Cache for inserted objects at 20.
Check OpenOffice.org Quickstarter.

Now highlight Java on the left panel, uncheck Use a Java runtime environment

Click the OK button and close OpenOffice.org. Start it up again to experience the change in speed!

Create a mirror of a website with Wget

2009-05-10T08:55:00.000-07:00

GNU's wget command line program for downloading is very popular, and not without reason. While you can use it simply to retrieve a single file from a server, it is much more powerful than that and offers many more features.

One of the more advanced features in wget is the mirror feature. This allows you to create a complete local copy of a website, including any stylesheets, supporting images and other support files. All the (internal) links will be followed and downloaded as well (and their resources), until you have a complete copy of the site on your local machine.

In its most basic form, you use the mirror functionality like so:

$ wget -m http://www.example.com/

There are several issues you might have with this approach, however.

First of all, it's not very useful for local browsing, as the links in the pages themselves still point to the real URLs and not your local downloads. What that means is that, if, say, you downloaded http://www.example.com/, the link on that page to http://www.example.com/page2.html would still point to example.com's server and so would be a right pain if you're trying to browse your local copy of the site while being offline for some reason.

To fix this, you can use the -k option in conjunction with the mirror option:

$ wget -mk http://www.example.com/

Now, that link I talked about earlier will point to the relative page2.html. The same happens with all images, stylesheets and resources, so you should be able to now get an authentic offline browsing experience.

There's one other major issue I haven't covered here yet - bandwidth. Disregarding the bandwidth you'll be using on your connection to pull down a whole site, you're going to be putting some strain on the remote server. You should think about being kind and reduce the load on them (and you) especially if the site is small and bandwidth comes at a premium. Play nice.

One of the ways in which you can do this is to deliberately slow down the download by placing a delay between requests to the server.

$ wget -mk -w 20 http://www.example.com/

This places a delay of 20 seconds between requests. Replace that number, and optionally you can add a suffix of m for minutes, h for hours, and d for ... yes, days, if you want to slow down the mirror even further.

Now if you want to make a backup of something, or download your favourite website for viewing when you're offline, you can do so with wget's mirror feature. To delve even further into this, check out wget's man page (man wget) where there are further options, such as random delays, setting a custom user agent, sending cookies to the site and lots more.

More advanced wget usage:

No parent option

If you are doing a mirror, but you only want to mirror a subdirectory of the main site (for example, just /news/), you might run into a problem. Because many of the pages at /news/ link back to /, you'll inadvertently end up downloading the whole site.

The solution to this, pointed out by Todd in the comments, is to use the no parent option, -np.

In our example, we'd do:

$ wget -mk -w 20 -np http://example.com/news/

Update only changed files

Continuing in our mirroring scenario, another extremely useful option for preserving bandwidth on both sides is to update only the files that the server reports as changed.

This option is -N.

$ wget -mk -w 20 -N http://example.com/

Thanks to Paul William Tenny in the comments for that tip.

Random delay on mirror

And finally for our mirror-specific tips, you can also randomise the delay between downloads. There are several reasons you might want to do this, including sites that don't take kindly to being mirrored, even considerately, and block clients that they suspect of doing it (some bots can be pretty nasty, and you might be categorised as one of 'them').

Randomising the wait time - and combining with the user agent option below - can be steps to circumvent this automatic protection.

If you do find yourself using this feature for that reason, please continue to be considerate and follow any rules regarding the content you've been given. Mirror responsibly.

$ wget -w 20 --random-wait -mk http://example.com/

The wait value - 20 in this case - is used as a base value to calculate what the random wait times will be. They will alternate between 0 and 2 times that value (in this case, 0-40 seconds).

Custom user agent

Some sites might have some strange restrictions on what browsers can access it, or perhaps have different versions of a site depending on the browser used. I can't say I agree with sites that do this, unless there's a really good reason, but it shouldn't stop you from using wget for access.

Using wget, you can set a fake user agent string so that the program reports itself as a different browser.

$ wget -U "user agent" http://example.com/

Combine the -U option with any others you want, obviously. Here are a few user agents you can use to get you started:

IE6 on Windows XP: Mozilla/4.0 (compatible; MSIE 6.0; Microsoft Windows NT 5.1) Firefox on Windows XP: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.1.14) Gecko/20080404 Firefox/2.0.0.14 Firefox on Ubuntu Gutsy: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.8.1.14) Gecko/20080418 Ubuntu/7.10 (gutsy) Firefox/2.0.0.14 Safari on Mac OS X Leopard: Mozilla/5.0 (Macintosh; U; Intel Mac OS X; en) AppleWebKit/523.12.2 (KHTML, like Gecko) Version/3.0.4 Safari/523.12.2

That's it for now, if you have any more useful wget tips and tricks, share them in comments.

Installing Gentoo 2008.0 Live CD

2009-05-10T08:29:00.000-07:00

Traditionally, Gentoo Linux has been a distribution designed more towards the more experienced Linux user, perhaps the 'power user', if you will.

Its source-based package management and offering the user complete control over the system installation and configuration have meant that traditionally, it can be difficult to approach.

Having myself tried and failed to install Gentoo in the past, I thought I would take the recently released 2008.0 Live CD for a spin, and see what the installation process is like, and how easy it is to use and understand. So here goes.

You get started like any other Live CD - throw it in the drive, reboot and press Enter to boot in. Before the GUI even arrives, you'll be asked to pick a keyboard layout to use for the live CD, then eventually you will be greeted with this GDM login screen.

There's an autologin set here, so you just have to wait a few seconds for the live user to be logged in. Gentoo now uses Xfce as the default GUI environment, so it will load up (fast, as it always seems to be).

As expected, this is a fully usable Gentoo system at this point, albeit running Live, so of limited utility. A fair selection of packages are installed, included Firefox 2.0.0.14, in a 'Bon Echo' branded guise.

Still, we're interested in the installation procedure. Conveniently on the desktop is an installer shortcut. Actually there are two - a command-line based installer, and the graphical GTK+ version. I'll be using the latter.

There's no introduction or anything. As soon as you double-click the installer, you're thrown straight in at a partitioning screen. Provided you have a clean disk and don't mind Gentoo monopolising your hard drive, it's simple to click the Recommend Layout button for a one-click solution to this screen.

It does, however, give its power user base the ability to fully control how Gentoo will inhabit their hard drives.

Click Next at this point and you are right away doing mount points for those partitions you just set up (and any others you want too). This is usually saved for the tail end of distro installations, but the way that the Gentoo installer works means that it will mount all of these partitions for you in the live distro too for the install, so it is done at this point.

You don't get an awful lot of confirmation, so pretty much as soon as you hit Next, those partitions will be written to disk and a few files get copied over.

Once that initial set of files gets copied, you then go back into answering questions. Personally, I don't like this sort of do some work, then ask more questions, then do more work thing.

It reminds me of the Windows XP installation procedure - when you can never just answer questions and set it off doing its own thing, it requires constant supervision. The Gentoo install isn't nearly as bad, but the way it works doesn't feel very 'standard' in comparison to more mainstream Linux distros.

From this point on, you are asked about configuring network interfaces, your root password and setting up the different users for your newly installed system.

The users module could potentially be a little confusing without a fair bit of Linux experience, as you are asked to manually fill in details such as the user's shell, home directory and user ID. You can leave things blank for defaults, however.

The final step before the proper copying of packages happens is to choose any additional packages you need. If you want a graphical system at the end of the install, you'll need to make sure you check at least the xfce and xorg-x11 packages.

Finally, the proper copy operation gets started. This will probably take considerable time (it did in my VM installation, at least).

Once the copy is finished, just as abruptly as it begun, you are notified that the installation is complete and you can reboot into the installed system.

Conclusion

So, how easy is this to install?

It certainly doesn't require much specific knowledge of Gentoo or how it works, but neither is it for the faint hearted.

A significant body of previous Linux experience is expected, as you'll be on your own with respect to key concepts, such as partitioning, packages and users.

I imagine that in a 'safe' environment - i.e. a machine that didn't particularly matter, someone with only intermediate Linux skills could probably get through relatively easily and progress to using the distro.

Gentoo is still very oriented towards the more experienced user and the person who likes to endlessly fiddle with and tweak their system so it works exactly how they like it and has the maximum possible performance.

I don't remember how I fell down on installing in the past, but it certainly seems like an achievable feat for someone with some Linux experience now, and that in itself has lowered the bar to learning and using Gentoo.

They could try to make it even easier to install, but then I guess there might be complaints from those who do not want their installer to be 'simplified' any more.

People like control over their machines.

Cygwin - a Unix Environment and Shell on Windows

2009-05-10T08:22:00.001-07:00

If your daily routine means that you spend much of your time behind a Windows system, yet you love the power and flexibility of a Unix-based environment, it might be frustrating not to have access to the tools and environment that you want.

Alternatively, you might want to compile some Linux/Unix software, so that it can run natively under Windows.

Cygwin is a Linux-style environment for Windows, that gives you a set of libraries, a full Linux-style command line and a package manager so you can install many of the Unix programs you might be familiar with.

I thought I would take a look at Cygwin's latest release and show you how to install it and get up and running.

First of all, head on over to the site and download setup.exe. This is the main installer/package manager for Cygwin and by default you use it to do an internet-based install, i.e. the setup program itself will download the packages.

Once the installer is up and running, click Next to bypass the initial welcome screen. You will be given several options on how you want to obtain packages. In most cases, Install from Internet is fine here.

Next, choose the directory to install Cygwin to on your Windows machine. This directory will become your root (/) from within the Cygwin shell.

On the next screen, choose the temporary folder where packages will be downloaded before they are installed into Cygwin. If you want, you can use a Windows temporary folder, but if you want to keep the source packages files around so you don't have to redownload later, make it somewhere permanent.

Again, click the old Next button and choose whether you need to use a proxy. In most home computer situations, leave the defaults intact and move on.

The Installer will at this point go off and retrieve a list of the different download sites, or mirrors, available to you. Choose one geographically close to you in preference, but any of them should be fine.

Here, you need to choose the packages that you want to install. You can just leave this all as it is and move on, but if you want to install additional packages into Cygwin, follow these steps.

The categories can be either left at the Default setting, or you can choose to Install or Uninstall whole categories by clicking on the 'recycling' icon next to them (and the word 'Default').

For individual packages, expand a category and find the package you want. To install or uninstall it, add a check under the 'Binary' and/or 'Source' columns to grab what you want.

Once you're done choosing packages, click Next yet again to move on. You can always come back to this stage later by re-running the installer to add or remove packages.

Download and installation now takes place. Depending on the speed of your machine and how much you've asked to download, this could take a while.

Once the installation is finished, pick your Desktop and Start menu shortcut options and Finish.

Finally - that's the installation done! You can access Cygwin through the shortcuts you just made, or by browsing to the directory you installed it in and launching cygwin.bat.

You will be presented with a bash shell, just as on Linux, and all of the Cygwin packages you installed should now be available for use.

You can also access Windows programs and files through /cygdrive/[Windows drive letter].

And there you have it - a Linux compatible environment for your Windows machine. Cygwin isn't really for the faint hearted, or those without Linux/Unix CLI experience, but it is a very powerful platform to bringing many features of the Unix platform to a Windows machine in a native way.

You can even run X on it.

Install Ubuntu on your USB Drive

2009-05-10T08:04:00.000-07:00

Did you know that is ridiculously simple to install Ubuntu onto an external USB flash drive?

If you have a copy of the latest version of Ubuntu (at the time of writing that is 8.10), there is a very simple program that does it all for you.

You will need:

An Ubuntu 8.10 CD (or ISO image if already installed)
A USB drive with at least 700-800 MB free space

While you are booted into Ubuntu, go to System > Administration > Create a USB startup disk.

You'll need to choose the source disc image for Ubuntu. If you have your Ubuntu CD in the drive, this should appear in the list, so make sure it is selected. Alternatively, you can click 'Other' and specify where the .iso image of the Ubuntu CD is.

Next, plug in your drive and choose it as your destination drive (and double-check it's the right drive before going ahead).

You can also choose how much space will be reserved for saving data on the new drive, or turn data storage off (it will act just like the Ubuntu live CD).

That's it! Simply press Make Startup Disk and wait while the files are copied over.

On many modern PCs that are configured to allow USB boot, you should be able to just restart the machine with the USB drive plugged in and Ubuntu should boot straight from it!

It's a nice simple way to have a copy of Ubuntu in your pocket, wherever you go.

Installing Ubuntu 8.10 on a White MacBook

2009-05-10T07:55:00.000-07:00

Installing Ubuntu (or any other Linux) on a Macintosh is a slightly different process than installing Ubuntu on a more traditional PC. Various differences in the hardware, particularly the use of the EFI firmware system, mean that some extra effort is required to get your favourite distro up and running on your favourite hardware.

This tutorial is inspired and somewhat derived from the Ubuntu Mactel Community Documentation, as well as my own experience of this process.

So let’s take a look at the steps involved, before we dive in.

Overview

We can divide the installation process into these major steps:

Make free space
Install rEFIt boot loader
Run Ubuntu installer (setting GRUB boot loader location)
Sync MBR with rEFIt
Boot the system and uninstall rEFIt

I will be installing Ubuntu 8.10 on a late 2006 white MacBook, so this guide may be somewhat specific to the white MacBook, but should be fairly similar on most Intel Macs.

Why?

Because the MacBook is a really nice piece of hardware. Many bits and pieces of the MacBook hardware work out of the box, including:

Graphics
- Intel GMA 950 and Intel GMA X1300 integrated graphics have open source drivers, so everything ‘just works’ out of the box, including desktop effects.
- The newer NVIDIA 9400M-based MacBooks will require the installation of the NVIDIA proprietary driver for full graphics support.
WiFi
- Support for the WiFi chip used in the MacBook is built right into recent revisions of the Linux kernel. The result? WiFi ‘just works’. Seriously.
Bluetooth
Audio
- After a little fiddle with the audio volume levels.

Backup, Backup, Backup

Before you do anything, make a full backup of your system. Anything you care about must be kept somewhere else as well, just in case this process goes wrong. A Time Machine backup should be fine, as long as you don’t forget to also backup the exceptions to your Time Machine backup separately if you don’t want to lose them.

Once you are completely confident that you could restore the entire system in a snap, or are convinced that you don’t care about anything on the machine, go ahead and continue with this tutorial.

Make Free Space

The first step is to make enough free space on your disk for Ubuntu to exist within. There are essentially two ways to achieve this. Unless you’re reinstalling Mac OS X from scratch anyway, it is probably a better idea to use the Boot Camp method, as you don’t have to delete everything to do so.

Using Boot Camp Assistant

Despite being designed for dual booting Windows and Mac OS X, Boot Camp Assistant is very useful to us as it automatically repartitions the hard drive on the fly, without deleting any of your data.

The space that you allocate to ‘Windows’ in this screen will, obviously, be the space that Ubuntu will occupy, so give yourself as much space as you think you will need.

Once you’ve clicked Partition, simply choose Quit and Install Later, as we won’t actually be installing Windows.

Now Boot Camp Assistant very helpfully formatted the partition as FAT32. Um, great, but we actually want free space. We’ll fix this from the Ubuntu side later.

By Reinstalling

If you happen to be reinstalling OS X anyway, you can use Disk Utility from within the Mac OS X Installer (in the Utilities menu) to partition the disk, manually creating a Mac OS Extended partition for OS X and deliberately leaving some space as unformatted.

Install rEFIt Boot Loader

In order to fix the system’s Master Boot Record (MBR) after the Ubuntu install is complete, we need to briefly install rEFIt, a custom bootloader for EFI-based computers, including Intel Macs.

Go ahead and download the Mac disk image and run the installer package.

Once it is complete, reboot the Mac and verify that you get a screen that looks something like the following (it won’t have a Tux icon yet and shouldn’t have a Windows icon either).

OK, we’re finally ready to kick off the Ubuntu install.

Run Ubuntu Installer

For the most part, this process is exactly the same as you would do on a PC. There are, however, two crucial steps you must get right.

Before getting started on the install, however, we need to get rid of the FAT32 formatting of the Boot Camp partition. Pop the Ubuntu CD into your computer and reboot. At the rEFIt boot menu, you can choose to boot Linux from CD. I recommend you plug in a USB mouse at this point so you can right-click.

Select Try Ubuntu without any change to your computer to get into the full Ubuntu interface. Once the system boots, go to Applications > Accessories > Terminal.

$ sudo gparted

This opens the partition editor, so we can go ahead and wipe that partition.

You’ll want to find the FAT32 partition labelled ‘Boot Camp’ (NOT the one labelled ‘EFI’ at the start), right-click it and choose Delete. Apply the changes.

Once the changes are applied, you can continue with the installation, as normal, except the following two things which must be set correctly:

Choose ‘Largest Continuous Free Space’

When you are asked by the installer how you want to partition the disk, choose Guided – use largest continuous free space. Since you just made sure you have a large chunk of free space earlier, by deleting the Boot Camp FAT32 partition, it will recognise that and use the space for Ubuntu.

If you are desperate to partition it yourself and know what you are doing, just make sure the bootable partition is the first one. Don't put your swap before your data on the disk, or the Mac will try to boot from the swap partition.

Install GRUB on sda

At the final page of the installer, ‘Ready to install’, where you are shown all the settings for the install, make sure you click the Advanced button and choose to install GRUB onto /dev/sda3.

Sync MBR with rEFIt

So, the installation should finish and you will be told to reboot. When the system comes back up, do not jump straight away into the new Linux option on your rEFIt boot menu.

Instead, select the Partition Tool icon. It should tell you that the Master Boot Record need to be synced and offer to do so. Press the Y key to accept this and you will return to the boot screen.

I recommend at this point you select the option to shut down your Mac, give it a few seconds to clear everything out and then turn it back on. This avoids a lockup I experienced right after you perform the MBR sync.

Boot the System and Uninstall rEFIt

At this point, you should be ready to go. At the rEFIt boot menu, choose the Linux option and Ubuntu should boot. At this point, everything should be just the same as it would be on a PC.

You can now uninstall rEFIt if you desire, or you can leave it intact and use it each time the system boots to choose your operating system. The choice is entirely up to you.

If you remove it, you can boot into Ubuntu with the Mac’s native boot loader by holding down the Option key at startup and choosing the disk entitled ‘Windows’.

Conclusion

And that’s it. After you’ve done this little bit of fiddling to get it installed, and perhaps once you have configured some components that don’t work out of the box, you have a very nice little Ubuntu machine.

Restoring an Overwritten GRUB Boot Loader

2009-05-09T13:43:00.000-07:00

I like to have lots of choice about which operating system I can boot to. Between my desktop PC’s two hard drives, I have at least three distributions of Linux and several versions of Windows, so I have complete OS flexibility.

Unfortunately, maintaining a multi-boot configuration like this can be a pain, especially if you later install an operating system which overwrites the GRUB boot loader you had in place (such as a version of Windows). If your boot loader is overwritten, you could be left with no choice but to boot the most recently installed OS.

In this tutorial, I will show you how to restore an overwritten copy of the GRUB boot loader by using a Linux live CD. In this example, my master GRUB installation is on a Kubuntu 8.10 installation, and I’m using an older Kubuntu 8.04 Live CD I have lying around.

This tutorial does require you to have some understanding of how your multi-boot system operates, disk partitions and using the command line. If you are not confident, perhaps find a friend who knows Linux more intimately to do this process.

Before Starting

It’s worth mentioning that you may need to use a live CD somewhat similar to that of your ‘master’ OS, where your boot loader configuration is stored. This is due to the technique we use to re-run the GRUB installer.

Also, you need to actually know which system holds the configuration file for your GRUB boot loader and on which partition it is located. If you have a more complicated multi-boot setup, like myself, you probably know this. If you have a more simple Windows-Linux dual boot, there should only be one Linux data partition where it could be.

Boot the Live CD

Start the Live CD up as normal. Don’t choose to install the OS if prompted, you want to come to a full live desktop to run the specific commands we need.

Identify your Partitions

You need to know on which partition the GRUB config file and associated programs are stored. You may wish to use a graphical program such as Gparted (if available). You’ll want to find out the device string (such as sda5) of the relevant partition.

(The screenshot above is actually from my triple-boot MacBook, but still shows you how you can identify the (ext3) partition of Ubuntu on that system.)

If you can’t use a graphical program to work this out, open a Terminal program and use the following command:

$ sudo fdisk -l

This will list all of the partitions on all the devices on your system. Under the ‘System’ column, you can see all of the partitions labelled as ‘Linux’. This won’t show you the difference between data and OS partitions, so is less useful in a more complex partition layout.

If you can work out where your Linux is from this, note down the information under ‘Device’.

Mount the Partition

We now must mount your partition, so that we can access it. Some Live CDs may do this for you, or offer to do so, but here we will perform the process manually.

We will first make a folder in which the partition is mounted and then do the mounting. Replace the device string /dev/sda5 with the device string that you identified earlier.

$ sudo mkdir /mnt/system
$ sudo mount /dev/sda5 /mnt/system

You should now be able to browse your hard drive by navigating to that folder. The next process we are going to perform is to temporarily change the root directory of our terminal (chroot), so that we can run the GRUB installer directly from the hard drive. It won’t even realise it’s not running from the real system

On Ubuntu and other sudo-based distros, we must first do this:

$ sudo -i

to become root fully (sudo is not enough here).

Doing the chroot

The GRUB installer requires to read the devices on disk directly in order to write the GRUB boot record back onto the system properly. It therefore needs a working copy of /dev, inside the mounted directory.

# mount -o bind /dev /mnt/system/dev

Next, we can run chroot:

# chroot /mnt/system

From this point forward, be very careful. You have root privileges and full write access to your hard drive. The usual caveats apply.

Run the GRUB Installer

All we need to do now is to simply run the GRUB installer, which plonks the GRUB boot record back on the hard disk and gives us back all of our choices.

# grub-install /dev/sda

If you need to install GRUB elsewhere (such as a different disk or a specific partition), change /dev/sda. In most cases, just leave this as-is.

GRUB should be re-instated on disk. You can now simply close your terminal, reboot the machine safely and everything should be back to normal.

Speed up your system by avoiding the swap file

2009-05-09T13:40:00.000-07:00

Most modern operating systems are capable of using a file or partition known as a swap or paging file. Most Linux distributions will also install one for you by default. This file is used to extend the amount of available RAM by writing some of it to your hard drive.

There's just one problem: hard drives are slow. We can't fix that problem yet, but we can avoid it. The Linux kernel provides a tweakable setting that controls how often the swap file is used, called swappiness. A swappiness setting of zero means that the disk will be avoided unless absolutely necessary (you run out of memory), while a swappiness setting of 100 means that programs will be swapped to disk almost instantly.

My Ubuntu system comes with a default of 60, meaning that the swap file will be used fairly often if the memory usage is around half of my RAM. You can check your own system's swappiness value by running:

cat /proc/sys/vm/swappiness

My HDD is insanely slow and I have 2 GB of RAM, so I'd like to turn that down to 10 or 15. The swap file will then only be used when my RAM usage is around 80 or 90 percent. To change the system swappiness value, open /etc/sysctl.conf as root. Then, change or add this line to the file:

vm.swappiness = 15

Reboot for the change to take effect. You can also change the value while your system is still running:

sysctl vm.swappiness=15

However, you won't get the full effect of rebooting because there is probably already memory stored in swap that won't instantly be moved out.

Update: Readers have noted that you can clear your swap by running swapoff -a and then swapon -a as root instead of rebooting to achieve the same effect.

Generating Website Statistics With Piwik, An Open-Source, Google Analytics-Like Web Analytics Tool - Page 2

2009-05-09T12:43:00.001-07:00

Now fill in a user name for the Piwik administrator (e.g. admin), a password for that user, and the email address of that user. This is the username and password that you'll need later on to log into Piwik:

You can configure Piwik to generate reports for multiple web sites later on, but during the installation, we configure Piwik for our first (and maybe only?) web site. Fill in a name for that web site and its URL:

Afterwards, Piwik will display a Javascript code for that web site. Copy it and paste it right above the tag of all pages belonging to the web site that you've configured in the last screen (www.example.com):

Click on Next afterwards:

The installation is now finished. Click on Continue to Piwik:

3 Using Piwik

Now log in with the account you've created during the installation:

This is the Piwik Dashboard (in my example it's quite empty, but on a real-life system, you should see quite a lot statistics after some time):

You can manage Piwik by clicking on the Settings link in the upper right corner. Here you can enable or disable Piwik plugins,...

..., manage users and access permissions,...

... and add further web sites (you will get a unique Javascript code for each web site):

4 High-Traffic Web Sites

The Piwik reports are generated in real-time which can make the Piwik web interface a little bit slow on high-traffic web sites. Therefore you should set up a cron job (as described on http://piwik.org/docs/setup-auto-archiving/) that generates the reports once a day - the Piwik interface should then react faster again:

crontab -e

MAILTO="falko@example.com"
5 0 * * * www-data /var/www/example.com/web/piwik/misc/cron/archive.sh

(This generates the reports each day at 00:05h. Make sure you use the correct user name for the web server. On Debian/Ubuntu, it's www-data, on Fedora/CentOS, it's apache.)

Make the /var/www/example.com/web/piwik/misc/cron/archive.sh file executable:

chmod 755 /var/www/example.com/web/piwik/misc/cron/archive.sh

Then run it manually to see if it throws any errors:

/var/www/example.com/web/piwik/misc/cron/archive.sh

If you see something like this...

[root@server1 cron]# /var/www/example.com/web/piwik/misc/cron/archive.sh
/var/www/example.com/web/piwik/misc/cron/archive.sh: line 20: /usr/bin/php5: No such file or directory
[root@server1 cron]#

... run...

which php

... to find out where PHP is located...

[root@server1 cron]# which php
/usr/bin/php
[root@server1 cron]#

... and edit /var/www/example.com/web/piwik/misc/cron/archive.sh:

vi /var/www/example.com/web/piwik/misc/cron/archive.sh

Change PHP_BIN; also adjust the PIWIK_PATH variable:

[...]
PHP_BIN=/usr/bin/php
PIWIK_PATH=/var/www/example.com/web/piwik/index.php
[...]

Then run

/var/www/example.com/web/piwik/misc/cron/archive.sh

again. It shouldn't throw any errors anymore.

Generating Website Statistics With Piwik, An Open-Source, Google Analytics-Like Web Analytics Tool

2009-05-09T03:18:00.000-07:00

This guide explains how you can install and use Piwik for generating website analytics. The reports generated by Piwik are similar to the ones generated by Google Analytics. Piwik is an Open-Source (GPL) tool that you can download and host on your own servers which means you are in full control over your data. In addition to that, Piwik's functionality can be extended by plugins.

I do not issue any guarantee that this will work for you!

1 Preliminary Note

I'm using the web site www.example.com here with the document root /var/www/example.com/web/. I'm assuming that the web site is working, and that PHP 5.1 or newer is installed on the server. I'm also assuming that you have an empty MySQL database that you can use for the Piwik installation. I'm using the database c0piwik with the database user c0piwik and the password piwik here (ask your hoster to create an empty MySQL database for you, or create it yourself through your control panel, e.g. ISPConfig).

2 Installing Piwik

Download Piwik to your desktop and unzip it. This will give you a folder latest/piwik/. Upload the piwik/ folder to your document root (e.g. with FTP). In my case where the document root is /var/www/example.com/web/ this will result in a folder /var/www/example.com/web/piwik/.

Now open a browser and go to http://www.example.com/piwik to start the Piwik installer. If you see something like this...

... either run the shown commands in the command line (if you have shell access)...

chmod 777 /var/www/clients/client0/web1/web/piwik/tmp
chmod 777 /var/www/clients/client0/web1/web/piwik/tmp/templates_c
chmod 777 /var/www/clients/client0/web1/web/piwik/tmp/cache

(In my installation, /var/www/example.com/web/ is a symlink to /var/www/clients/client0/web1/web/, that's why you see /var/www/clients/client0/web1/web/ instead of /var/www/example.com/web/ here in the screenshot and the command.)

... or change the folder permissions in your FTP client:

(In my installation, the tmp/ folder was empty, so I did not have to change permissions for tmp/templates_c and tmp/cache.)

Then refresh the Piwik page in your browser. You should now see the welcome page of the installer. Click on Next:

On the next page, the installer performs a system check to see if all prerequisites are fulfilled. If there's a problem with the config folder,...

... scroll down, and you should see the command to execute to solve the problem (if you don't have shell access, you can as well fix the permissions with your FTP client):

After you have fixed the problem, scroll down and click on the Refresh the page link:

The system check should now succeed. Click on Next:

Now we come to the database settings. Fill in the database name of your empty database as well as the database user and the password. You can leave the table prefix (piwik_) as it is. The same goes for the MySQL server (localhost) unless it is located on a remote server:

The installer creates the necessary database tables. Click on Next:

Page 2

Rescuing a Lost Root Password

2009-05-09T03:09:00.000-07:00

Sometimes you wind up taking over a machine for which the root password has been lost. Here are a couple of solutions.

Reboot (hard reboot by pulling the power cable if rebooting requires the root password), and hit 'e' to edit the boot line when you get to the grub menu. Scroll down to the line that starts with kernel, then hit 'e' again to edit it, add 'single' to the end, and hit Enter to accept. Now 'b' to boot and eventually you'll be dumped into a root shell. From here type passwd to change the root password.

Some systems require the root password to boot into 'single' mode. In this case, try editing the grub boot line to add 'init=/bin/bash' to the end of the kernel line. This will boot you into a very basic system, using the bash shell instead of init. You may have to mount the root partition read/write:

mount -no remount,rw /

Then use passwd to reset the password.

If grub is protected, try booting from a LiveCD or USB stick. Open a root shell, and use fdisk -l to show the available disk partitions. Mount the root partition with

mount -o,rw /dev/hda1 /mnt

Check it's the right directory with ls /mnt, then change into that as your root directory:

chroot /mnt

Now use passwd as before.

NOTE: It's important to bear in mind that all of these are also potential security risks if people have physical access to your machines.

Linux Proves - The Best Things In Life Are Free

2009-05-08T10:58:00.000-07:00

They say - there's no such thing as a free lunch. But, Linux and FOSS software can be used to start, run and grow your business for, you guessed it, free. February survey of IT managers by IDC indicated that hard times are accelerating the adoption of Linux. The open source operating system will emerge from the recession in a stronger data center position than before, concluded an IDC white paper. Reducing costs and stronger interoperability with Windows were listed as the two top issues in a new survey of IT managers.

Sun Microsystems, Novell, Microsoft and many more have been down because of bad economy. But, Free software vendor such as Red Hat, IBM and others are doing fine. Here in India, many Government projects and schools found success with Linux. Also, Linux found good successes in emerging economies where Microsoft Windows doesn't already dominate end user computing. The increasing use of Linux as a pre-loaded system on mobile devices is another area where Linux use is likely to grow on.

However, Linux may be free, but you still need to invest in the training and getting involved in the community to get support. What do you thing? Have you found success with Linux in your data center? Please add your thoughts in the comments below.

Tricks To Increase Your Firefox Speed By A Noticeable Amount

2009-05-05T23:37:00.000-07:00

Hello. With this simple detailed tutorial I will show you how to increase the speed of Firefox by 10-30 times.

Firefox is a well known open source browser and is widely used around the world for it being secure, stable and fast.

But by default few settings are disabled in this which makes it bit slow sometimes. With this tutorial you will be able to explore the hidden speed of Firefox which will boost the speed of Firefox and make your Firefox lightning fast.

Download the latest version of Firefox from here. Now install the Firefox.

To speed up Firefox follow these steps.

For those who are unsure about the changes, please first refer to this post:
Backup Firefox Profile And Restore It!

01. Type about:config in the address bar and then press Enter.

And you will see a confirmation message like this:

Now click I'll be careful, I promise!

02. You will see a label there Filter, just next to it type network.http.pipelining. Now be sure the value field is set true, if not double-click to set true.

Info: HTTP is the application-layer protocol that most web pages are transferred with. In HTTP 1.1, multiple requests can be sent before any responses are received. This is known as pipelining. Pipelining reduces page loading times, but not all servers support it!

03. Go back to the Filter search bar and type network.http.pipelining.maxrequests. Double-click this option and set its value to 8.

04. In the Filter search bar and type network.http.proxy.pipelining. Once opened double-click on it and set it to true.

05. Type network.dns.disableIPv6 in the filter search bar and set this option to true by double clicking on it.

Info: In IPv6-capable DNS servers, an IPv4 address may be returned when an IPv6 address is requested. It is possible for Mozilla to recover from this misinformation, but a significant delay is introduced.

06. CONTENT INTERRUPT PARSING
This preference controls if the application will interrupt parsing a page to respond to UI events. It does not exist by default.
Right-click (Apple users ctrl+click) anywhere in the about:config window, select New and then Boolean from the pop-up menu. Then:

A. Enter content.interrupt.parsing in the New boolean value pop-up window and click OK.

B. When prompted to choose the value for the new boolean, select true and click OK.

07. Rather than wait until a page has completely downloaded to display it to the user, Mozilla applications will regularly render what has been received to that point. This option controls the maximum amount of time the application will be unresponsive while rendering pages.

Right-click (Apple users ctrl+click) anywhere in the about:config window, select New and then Integer from the pop-up menu.

A. Enter content.max.tokenizing.time in the New integer value pop-up window and click OK.

B. You will be prompted to enter a value. Enter 2250000 and click OK.

08. CONTENT NOTIFY INTERVAL
This option sets the minimum amount of time to wait between reflows. Right-click (Apple users ctrl+click) anywhere in the about:config window, select New and then Integer from the pop-up menu.

A. Type content.notify.interval in the New integer value pop-up window and click OK.

B. You will be prompted to enter a value. Enter 750000 and click OK.

09. CONTENT NOTIFY ONTIMER

A. This option sets if to reflow pages at an interval any higher than that specified by content.notify.interval. Right-click (Apple users ctrl+click) anywhere in the about:config window and select New and then Boolean from the pop-up menu.

B. Type content.notify.ontimer in the New boolean value pop-up window and click OK.

C. You will be prompted to choose the value for the new boolean. Select true and click OK.

10. Notify Backoffcount
This option controls the maximum number of times the content will do timer-based reflows. After this number has been reached, the page will only reflow once it is finished downloading. Right-click (Apple users ctrl+click) anywhere in the about:config window and select New and then Integer from the pop-up menu.

A. Enter content.notify.backoffcount in the New integer value pop-up window and click OK.

B. You will be prompted to enter a value. Enter 5 and click OK.

11. CONTENT SWITCH THRESHOLD
You can interact with a loading page when content.interrupt.parsing is set to true. When a page is loading, the application has two modes: a high frequency interrupt mode and a low frequency interrupt mode. The first one interrupts the parser more frequently to allow for greater UI responsiveness during page load.

The low frequency interrupt mode interrupts the parser less frequently to allow for quicker page load. The application enters high frequency interrupt mode when you move the mouse or type on the keyboard and switch back to low frequency mode when you had no activity for a certain amount of time. This preference controls that amount of time. Right-click (Apple users ctrl+click) anywhere in the about:config window and select New and then Integer from the pop-up menu.

A. Enter content.switch.threshold in the New integer value pop-up window and click OK.

B. You will be prompted to enter a value. Enter 750000 and click OK.

12. NGLAYOUT INITIALPAINT DELAY
Mozilla applications render web pages incrementally, they display what??™s been received of a page before the entire page has been downloaded. Since the start of a web page normally doesn't have much useful information to display, Mozilla applications will wait a short interval before first rendering a page. This preference controls that interval. Right-click (Apple users ctrl+click) anywhere in the about:config window and select New and then Integer from the pop-up menu.

A. Enter nglayout.initialpaint.delay in the New integer value pop-up window and click OK.

B. You will be prompted to enter a value. Enter 0 and click OK.

That's it! Now restart Firefox and your browsing as well as downloading speed will be much more faster. Good luck.

HowTo Increase Firefox Page Transfer Speed Up

2009-05-05T23:29:00.000-07:00

Your webmaster search is: why firefox users increasing

In this brief tutorial, learn how to easily make Firefox load pages up to 40% faster !

Firefox, when tweaked in this manner, will render faster than Opera.

Type about:config on the Firefox address bar and hit Enter.

This will display an alphabetical listing of preferences by name, as well as a search bar at the top.

Type network.http.pipe on the Filter search bar.

A narrowed down list will appear showing preferences network.http.pipelining and network.http.pipelining.maxrequests and their current values.

Double-click on the network.http.pipelining string to change its value to true if not already. [see notes 1 & 2]

Double-click on the network.http.pipelining.maxrequests string and change the current value in the Enter interger value box to 34 and click ok. [see note 3]

To enable the turbo feature in Firefox you will need to manually create a preference.

Right-click anywhere on the page and select New and then Boolean.

Enter browser.turbo.enabled as the preference name in the New boolean value box and click ok, and then set the value in the Enter Boolean value box to true.

That's it, now simply close and restart Firefox, and you should see an immediate 10% to 40% increase in web page transfer speed, and faster opening of your tabbed windows !

note 1:

The Boolean preference network.http.pipelining enables an experimental acceleration technique called pipelining, which speeds up the loading of most Web pages. A browser normally waits for some acknowledgment of a given request from a server before attempting to send another one to that server; pipelining sends multiple requests at once without waiting for responses one at a time.

note 2:

If you use a proxy, set network.http.proxy.pipelining to true as well.

note 3:

The integer preference network.http.pipelining.maxrequests controls the maximum number of requests that can be pipelined at once. There's not much evidence that going above 34 will help.

Resources for Learning Howto Customize Your Browser

2009-05-05T23:01:00.000-07:00

No matter which browser you prefer, there’s a plethora of ways to customize the way you surf the Web. There are countless plugins, extensions, toolbars and more. Some of these are easy to install while others require a little more effort.

We’ve put together a list of some of the best instructional resources for the most popular browsers today, including Microsoft Internet Explorer, Mozilla Firefox, Safari, Opera and even the still wet behind the ears rookie, Google Chrome ().

Internet Explorer ()

ie Tips - Shares a ton of quick tips for customizing Internet Explorer.

Official Browser Settings - Overview provides plenty of useful information on all of the settings for IE that most users never touch. Learn what they do and perhaps fix some problems you’ve been experiencing.

Official IE Developers Blog - Shares new tips and tricks all the time on their official blog for Internet Explorer.

Internet Explorer Toolbar - Tutorial covers what you need to know about IE’s toolbar.

Top 11 ie Add-ons - Covers a list of cool tools you can add to the IE experience.

Firefox ()

Customize Firefox themes - Provides a large collection of new themes for changing your Firefox look and feel.

Mozilla’s Official Way to Customize Firefox - shows undocumented features and ways to customize their browser.

How to Use GreaseMonkey - A must-read if you truly want to take your browsing to the next level.

Office Firefox Add-on Library - Contains an amazing amount of add-ons that you can install with a simple click.

Mashable’s List of 30+ Firefox Extensions - Extensions that enhance your browsing experience.

Safari ()

How to Customize Safari Beyond All Reason - Offers up a bunch of solutions to common annoyances with Safari as well as other cool tips. Funny title too.

How to customize the Safari Toolbar - Covers everything you need to know about the toolbar.

SafariStand - Adds dozens of extra features to the Safari browser.

eHow’s How to Customize Safari covers the basics of Safari preferences here.

YouTube video - Shows you how to customize the Safari Toolbar.

Opera ()

Opera Mini - How to install and configure Opera Mini for your mobile device

Official Opera Tutorials - Tutorials on how to customize the Opera browser.

Opera Widgets - Shows the best ways to customize Opera Widgets.

Extending Opera - Demonstrates several ways to get the most out of Opera.

Opera Mail Tutorial - A nice visual tutorial on the Opera Mail system.

Chrome ()

Google Chrome Forums - Has a tremendous amount of ways to trick out your Chrome browser

Digital Streets - Shares some cool tips for customizing your Chrome experience.

Custom Search Engines - Covers how to change the search engines in Chrome

Customized Chrome Themes - Gives you ideas on how to change Chrome’s skin.

GreaseMetal - The Chrome equivalent to Firefox’s popular GreaseMonkey.

Whether it’s just to save time or make your browser more visually appealing, there’s an amazing amount of options for any browser that you choose to use. What are some of your favorite ways to trick out your browser? Are there any unusual things you do that others might like to try? Share your secrets in the comments area.

Coolest Opera Tips & Tricks

2009-05-05T22:34:00.000-07:00

As we know, Opera is an extremely customizable browser, but it does so much that it can be difficult to remember it all. Then again you would have to know what it does in order to remember it.

Today we want to walk you through a dozen tips and tricks that will inch you closer to becoming an Opera grand master. So lets go ahead and jump into it, and as always, hit us up with your tips in the comments!

–Bookmark & Folder Nicknames–

Opera has a nickname feature for bookmarks that I’m guessing most people use. With it you can enter in an abbreviation for a bookmark that can quickly be typed into the address bar to pull up a particular site. One thing that you may not have realized is that the nicknames can also be assigned to entire folders of bookmarks, and entering that into the address bar will open every site within that folder:

–Bookmark & Open Multiple Links–

Let’s say you’re on a sight such as Digg, and you’re trying to quickly go through all of the news. Enter Links Panel! The Links Panel (a.k.a. sidebar) will let you handle hyperlinks throughout the page in bulk. You can Ctrl+Click or Shift+Click to select multiple links from the current page. Then just choose the bookmark or open the option from the right-click menu.

–Click to Save Images–

Do you find yourself frequently saving images from websites? Instead of right-clicking on an image to save it each time, just Ctrl+Click on it. You’ll immediately be prompted with a Save As dialog box for you to enter in the name, or you can just press Enter to use the image’s current name.

[via Opera Watch]

–Customize the Browser’s Name and Icon–

Did you know that you change the name of the browser, and even replace its icon with your own? Yep, that’s all built-in. To change the icon you’ll need to enter opera:config#UserPrefs|ApplicationIcon into your address bar, and then provide the location of the icon you want to use.

To change the browser’s name, just enter opera:config#UserPrefs|Title into the address bar, and in the box type the name you want to appear. Additionally, you can use these combinations to insert dynamic items:

%t for page title (entering just %t in the box will remove the browser’s name all together, which is what I currently do)
%s for build number
%v for version number

–Detach/Move a Tab–

Want to open a tab up in a new window? Just drag it onto the title bar of the browser. You can also move tabs between multiple windows simply by dragging and dropping them from one tab bar to another.

–Fast Navigation–

If you’re trying to open several links on a page, you should try using Shift+Arrow keys to move between the hyperlinks on the page. The nice thing is that this doesn’t jump back up to the beginning of the page where the first hyperlink appears. It starts with the first hyperlink in the area that you are looking at.

Shift+Ctrl+Enter will then open the currently selected link in a background tab.

–Fit to Width–

When you come across a site that requires horizontal scrolling, why not try and enable the Fit to Width feature (located in the View Menu, or press Ctrl+F11). The site will be adjusted so that no horizontal scrolling is necessary, and for the most part it won’t look all that bad.

–Hide the Menu Bar–

I hardly ever need to use the Menu Bar, and it takes up more room that I’m willing to part with. So what I do is I add a button that will remove the Menu Bar, and at the same time provide all of the menu options in a single condensed drop-down list. Just click here to add that button, and for more menu buttons visit the Opera Wiki.

–Hide the Tab Bar for a Single Tab–

In Firefox when you only have one tab open, the tab bar is not visible, and there is an option in Opera to do the same thing. Just right-click on the Tab Bar, choose the Customize option, and then check the box that says “Show only when needed.” The tab bar will now be hidden anytime only one tab is open.

–Right-Click Address Mapping–

It’s super easy to map any address on a site using your favorite map service. Here’s what you have to do:

Open up your favorite map service (ex. Google Maps or Yahoo! Maps).
Right-click in the service’s search box, and choose the Create Search option. Enter in a keyword (it’s required by Opera, but isn’t used in this trick), and then press Save.
The next time you see an address on a site just highlight it with your mouse, right-click, and then go to “Search with.” You’ll see a list of all the possible search engines that you’ve added to Opera, and all you have to do is select the mapping service.

–Promptless Downloading–

If you’re like me you probably save all of your downloads to the same folder so that you don’t end up with things scattered all over your computer. In Opera you can set your default download location in the Options, and then when you right-click on a file or image, there will be a “Save to download folder” option. Clicking on that will initiate the download without prompting you for any information.

–Speed Dial Homepage Button–

This is something that I was yearning for, and luckily the Opera Community came through. For reasons unknown to me, the Opera developers never associated an address to the Speed Dial page. That meant you couldn’t assign it as your browser’s homepage, but dragging this button onto the address bar will do the trick. It will take on the look of the homepage button, but it will actually open the Speed Dial page.

How to increase boot speed and overall performance?

2009-05-04T22:35:00.000-07:00

Add more RAM to your system. If you are using PCLinuxOS 2007 or 2008, it’s suggested that you should use more than 512 MB RAM. Configure your system to use more RAM and less or no swap.

Check your hardware if your system have right kind of drivers installed. For example, if you have Intel GMA 965 graphics card and your system boots to a vesa driver the you will have disappointing graphics performance.
Customize runlevels as per your computing needs. If you are using internet via cable and always booting to a multiuser graphical environment then you should disable all the runlevels except 0, 5 and 6 (as per pclinuxos settings).
Remove unnecessary gettys if you are not using them anymore. Home user generally don’t need any kind getty.
Change the bios settings to boot directly from HDD because modern bios are set to choose usb devices and optical drives to seek for boot information. If you have installed PCLinuxOS on your HDD you should disable usb and cd/dvd boot seeking options in BIOS.
Remove unnecessary services. As for myself I have disabled ntp, portmap, partmon, at, anacron, netfs, kheader, cups, sane and many more…
Remove unnecessary icon sets, themes and desktop environment extra packages.
Disable system startup checking
Use light weight programs. If rxvt does your purpose there no need to use console and if abiword is sufficient for your needs you should remove OO.o.
Use initng for system booting, it is more advanced and faster than the traditional SysVinit.

How to improve video playback quality?

Some people have problems playing videos and are getting washed out colors with too much brightness. They modify the driver preferences for the X11 server to get better quality with Kaffeine and Mplayer.

For Mplayer, to to Preferences, Video and choose the X11 (Ximage/Shm) drivers.
For Kaffeine player go to Settings, Xine Engine Settings and choose the opengl drivers.

How to configure Kaffeine and Amarok to play real player and Win32codec audio?

Kaffeine and Amarok are installed in your PCLinuxOS are installed by default. You need win32codecs package to be used by Kaffeine and Amarok to play realmedia and windows media audio.

1) Install win32codecs through Synaptic Package Manager.

2) Kaffeine steps

a) start Kaffeine

b) click menu->settings->xine Engine Parameters

c) choose decoder options

d) change /usr/lib/real/ to /usr/lib/win32/

e) change /usr/lib/codecs to /usr/lib/win32

3) Amarok steps.

a) Make sure Amarok is closed

b)Open with your preferred text editor the Amarok “xine-config” file located in “~/.kde/share/apps/amarok/”.

This can be done by issuing the following run command (click ALT+F2 to bring the run command dialog)

kwrite ~/.kde/share/apps/amarok/xine-config

* The “xine-config” file has many entries, but we are only interested in changing two values, path to RealPlayer codecs and path to Win32 codecs.

c) Change #decoder.external.real_codecs_path:/usr/lib/real/ to decoder.external.real_codecs_path:/usr/lib/win32/

* If the value for #decoder.external.real_codecs_path is empty also change it to decoder.external.real_codecs_path:/usr/lib/win32/

d) Change #decoder.external.win32_codecs_path:/usr/lib/codecs to decoder.external.win32_codecs_path:/usr/lib/win32

e) Make sure your removed the '#' at the beginning of both modified lines. Otherwise, Amarok will use the default values instead of the new values.

f) Save the file and close kwrite.

4) Enjoy listening to and watching real media and QuickTime in your players Smiley

By default Amarok does not play some files with the .ram extension. Rename files with .ram extensions to .rm, after that Amarok will play them.

How to join video files?

Mencoder offers you easy command line options to join video files as follows:

mencoder -oac copy -ovc copy file1 file2 file3 … -o final_movie.xxx

You can also use cat to join multiple files in a crude way as follows:

cat movie.avi.001 movie.avi.002 > movie.avi

How to access ext2 and ext3 filesystem within windows?

Install any one of the two apps in your windows to access ext2 and ext3 partitions:

Explore2fs: http://www.chrysocome.net/explore2fs

DiskInternals Linux Reader: http://www.diskinternals.com/linux-reader

How to speed up Openoffice?

Start Open Office and click on Tools > Options. This should open the configuration. Click on Memory in the left menu and change the following settings:

* Number of Steps: 30

* Use for Open Office: 128

* Memory per Object: 20

* Number of Objects: 20

Click on Java in the left menu afterwards and uncheck "Use a Java Runtime Environment". Click OK and restart Open Office to see how fast it is now.

How to cool hot laptops/desktops?

Cpufreq is a good tool for Linux. It clocks down the processor when the computer does not need power and clocks up when it needs power.

1. Go to synaptics

2. Search for cpufreq

3. If cpfreq is not installed, install it.

4. Go to Control Center, find cpufreq and mark “On boot”

How to improve downloading on Firefox?

Flashgot is a very good firefox extension that quite skilfully handles downloads. Integrate it with kget and enjoy fast downloading.

Set up a LAN gateway with DHCP, Dynamic DNS and iptables on Debian Etch

2009-05-04T22:22:00.000-07:00

Linux is a perfect platform to act as a router/gateway.

In this tutorial, I will explain how to set up a Linux box to operate as a network router. The box will provide the following services:

DHCP server to provide the ip addresses to the machines in the LAN
DNS server to resolve domain names
Gateway with IP tables to give access to the Internet.
Firewall with IP tables.

The resulting machine will have quite a small footprint: about 600M, and except if your network is intensively used, a low spec computer can be recycled to do the job.

As the machine is going to operate as a router/firewall

This tutorial is based on a Debian Etch 4.0 r3 minimal network install, i.e that during the install, at the "Software selection" step, I unselected everything.

The box has 2 network interfaces:

eth0: ip 192.168.1.9 which is connected to internet (not directly though, but it is the box that is routing the traffic toward internet for this LAN)
eth1: ip 192.168.2.1, this is the interface connected to our LAN and that will forward the traffic to and from internet.

Also, we are going to manage the domain name lan.debuntu.local, so each machine will be able to communicate with each others by using their hostname.

So first let's get started with the set up of bind9

1. DNS server

As a DNS server we are going to use bind9, it will be configured to resolve the names of the host for our network lan.debuntu.local.

The DNS server will also accept dynamic DNS update from the local DHCP server.

In this tutorial, I will be using the Dynamic DNS feature of bind.

1.1. Installing the DNS server

Make sure you are installing bind9 as older version of bind do not not support dynamic dns updates.

# apt-get install bind9

1.2. Configuring the DNS server

In order to keep the default install files clean, we are going to only edit /etc/bind/named.conf.local . In this file we are going to allow dns updates from local host using "rndc-key" (which is installed by default with bind9 package)

We are also going to define 2 zones:

lan.debuntu.local : our local domain name
2.168.192.in-addr.arpa : our local network ip zone, this will allow us to reverse lookup names.

So let's go and edit /etc/bind/named.conf.local and add:

#allow dns updates from localhost with key "rndc-key"
include "/etc/bind/rndc.key";
controls {
inet 127.0.0.1 allow { localhost; } keys { "rndc-key"; };
};

#defines lan.debuntu.local
zone "lan.debuntu.local" {
type master;
 file "db.lan.debuntu.local";
 allow-update { key "rndc-key"; };
};

#defines our local subnet 192.168.2.0/24
zone "2.168.192.in-addr.arpa" {
type master;
notify no;
file "db.2.168.192";
allow-update { key "rndc-key"; };
};

Then, we need to create those 2 files : /var/cache/bind/db.lan.debuntu.local and /var/cache/bind/db.2.168.192 .

The first one will be used to resolve names, while the second one to reverse name lookup.

/var/cache/bind/db.lan.debuntu.local will look like:

;
; Zone file for lan.debuntu.local
;
; The full zone file
;
$TTL 3D
@       IN      SOA     ns.lan.debuntu.local. postmaster.lan.debuntu.local. (
 200806281; serial, todays date + todays serial #
 8H              ; refresh, seconds
 2H              ; retry, seconds
 4W              ; expire, seconds
 1D )            ; minimum, seconds
;
 NS      ns              ; Inet Address of name server
 MX      10 mail         ; Primary Mail Exchanger
;
 A 192.168.2.1  ; IP address
;
router A   192.168.2.1
ns    CNAME router
dhcp  CNAME ns.lan.debuntu.local.
*     A       192.168.2.1

While /var/cache/bind/db.2.168.192 will look like:

$TTL 3D
@       IN      SOA     lan.debuntu.local. postmaster.lan.debuntu.local. (
200806281 ; serial, todays date + todays serial #
8H              ; refresh, seconds
2H              ; retry, seconds
4W              ; expire, seconds
1D )            ; minimum, seconds
;
@       IN      NS      ns.lan.debuntu.locl.
@ IN  PTR lan.debuntu.local.

1 IN PTR  router.lan.debuntu.local.

2. DHCP server

In order to provide an IP address to the other machines in the network, we need to use a DHCP server.
This DHCP server will provide the host with all the information needed to connect to any other accessible host. i.e, the IP, netmask, gateway, domain name server.
The DHCP server will also update bind with a nt set of hostname and IP when the client is requesting a specific hostname.

2.1. Installing the DHCP server

We are going to install the dhcp server packaged under the name of dhcp3-server. To install it, simply type:

# apt-get install dhcp3-server

Make sure you are installing dhcp3-server and not dhcp as the latter does not support dynamic dns updates.

2.2. Configuring the DHCP server

The configuration is all in /etc/dhcp3/dhcpd.conf.

In our set up, we want to give IPs in the range 192.168.2.0/24 and we want to set up our domain name to be lan.debuntu.local

We are only going to listen for DHCP queries on eth1 and thus will need to bind the service for only this specific address. To achieve this, go and edit /etc/default/dhcp3-server and make sure INTERFACES is set as follow:

... ... # On what interfaces should the DHCP server (dhcpd) serve DHCP requests? # Separate multiple interfaces with spaces, e.g. "eth0 eth1". INTERFACES="eth1"

Then, go and edit /etc/dhcp3/dhcpd.conf and make it look as follows:

#naming the server # and enabling ddns server-identifier router; authoritative; ddns-update-style interim; include "/etc/bind/rndc.key"; # Use what key in what zone zone lan.debuntu.local. { primary 127.0.0.1; key "rndc-key"; } #Standard DHCP info option domain-name "lan.debuntu.local"; option domain-name-servers ns.lan.debuntu.org; default-lease-time 600; max-lease-time 7200; log-facility local7; subnet 192.168.2.0 netmask 255.255.255.0 { range 192.168.2.5 192.168.2.200; option routers router.lan.debuntu.local; zone 2.168.192.in-addr.arpa. { primary ns.lan.debuntu.local; key "rndc-key"; } zone lan.debuntu.local. { primary ns.lan.debuntu.local; key "rndc-key"; } }

Which says that we provide IP addresses on the range 192.168.2.5 to 192.168.2.200, and the traffic for this network will be routed by router.lan.debuntu.local

On the top of this, the domain name to be used for dns ueries is lan.debuntu.local and the DNS server is machine ns.lan.debuntu.local

The host names where defined earlier in the DNS section, dhcp3-server will query his DNS server to find there IP. Only the IP will be sent back to the host clients.

Now our DHCP server should be ready, it is time to restart it.

# /etc/init.d/dhcp3-server restart

Same here, if anything goes wrong, /var/log/messages, /var/log/syslog and /var/log/daemon.log will be your friends.

At this stage, you should normally be able to provide IPs to all the host in the network, provide them domain name resolution service and all the host should be able to communicate with each others using hostnames.

BUT, except for the gateway, none of the host can connect to the internet.

3. Forwarding Internet traffic with IPtables

IPtables is both used to act as a firewall, but it is also the one passing packets from one network to another.

3.1. Enabling IP forwarding

IP forwarding is enabled at the kernel level. The way to enable it is to set /proc/sys/net/ipv4/ip_forward to 1.
This can be done during runtime by typing:

# echo 1 > /proc/sys/net/ipv4/ip_forward

To make those changes permanent upon reboots, edit /etc/sysctl.conf and make sure there is the following values:

net.ipv4.conf.default.forwarding=1
net.ipv4.conf.all.forwarding=1

3.2. Setting iptables rules

The next step is to set up iptables rules, the ones that will tell the kernel what to do with the packet depending on their states.

This firewall will only accept ssh connection from the WAN, anything from the LAN and will forward port 2222 from the WAN to machine 192.168.2.2 on port 22.

Here is the script used:

#!/bin/sh
#
# this script requires iptables package to be
# installed on your machine


# Where to find iptables binary
IPT="/sbin/iptables"
# The network interface you will use
# WAN is the one connected to the internet
# LAN the one connected to your local network
WAN="eth0"
LAN="eth1"
# First we need to clear up any existing firewall rules
# and chain which might have been created
$IPT -F
$IPT -F INPUT
$IPT -F OUTPUT
$IPT -F FORWARD
$IPT -F -t mangle
$IPT -F -t nat
$IPT -X

# Default policies: Drop any incoming packets
# accept the rest.
$IPT -P INPUT DROP
$IPT -P OUTPUT ACCEPT
$IPT -P FORWARD ACCEPT

# To be able to forward traffic from your LAN
# to the Internet, we need to tell the kernel
# to allow ip forwarding
echo 1 > /proc/sys/net/ipv4/ip_forward

# Masquerading will make machines from the LAN
# look like if they were the router
$IPT -t nat -A POSTROUTING -o $WAN -j MASQUERADE


$IPT -t nat -A PREROUTING -i $WAN -p tcp --dport 2222 -j DNAT --to-destination 192.168.2.2:22
$IPT -A FORWARD -i $WAN -p tcp  --dport 22 -m state --state NEW -j ACCEPT

# Do not allow other new or invalid connections to reach your internal network
$IPT -A FORWARD -i $WAN -m state --state NEW,INVALID -j DROP

# Accept any connections from the local machine
$IPT -A INPUT -i lo -j ACCEPT
# plus from your local network
$IPT -A INPUT -i $LAN -j ACCEPT

# log those packets and inform the sender that the packet was rejected
$IPT -N Rejectwall
$IPT -A Rejectwall -m limit --limit 10/minute -j LOG --log-prefix "Rejectwall: "
$IPT -A Rejectwall -j REJECT
# use the following instead if you want to simulate that the host is not reachable
# for fun though
#$IPT -A Rejectwall -j REJECT  --reject-with icmp-host-unreachable

$IPT -A INPUT -p icmp -j ACCEPT

# Accept ssh connections from the Internet
$IPT -A INPUT -i $WAN -p tcp --dport 22 -j ACCEPT

# or only accept from a certain ip
#$IPT -A INPUT -i $WAN -s 125.124.123.122 -p tcp --dport 22 -j ACCEPT

# Accept related and established connections
$IPT -A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT

# Drop netbios from the outside, no log, just drop
$IPT -A INPUT -p udp --sport 137 --dport 137 -j DROP

# Finally, anything which was not allowed yet
# is going to go through our Rejectwall rule
$IPT -A INPUT -j Rejectwall

Now, run the script:

# sh iptables.sh

All host within the LAN should now be able to access the internet!

now we have to make sure that the changes are permanent upon reboot.

3.3. Making iptables rules persistent

I like to be able to easily start and stop iptables using an init.d script. Unfortunately, this is gone from debian packages.

Anyhow, here is a script that you can copy to /etc/init.d/iptables :

#!/bin/sh

IPTABLES="/sbin/iptables"

# load options
if [ -f /etc/default/iptables ] ; then
. /etc/default/iptables
else
exit 1
fi

# Check for daemon presence
test -x ${IPTABLES} || exit 0

# Get lsb functions
. /lib/lsb/init-functions
. /etc/default/rcS

# Check for saved state
if [ x$1 != "xsave" ] && [ x$1 = "xstart" ] && ! test -r ${IPTABLES_SAVE}; then
log_warning_msg "Skipping iptables configuration..."
exit 0
fi

flush() {
if [ -f /proc/net/ip_tables_names ] ; then
 for table in `cat /proc/net/ip_tables_names`; do
   ${IPTABLES} -F -t $table
   ${IPTABLES} -X -t $table
   if [ $table = nat ]; then
     ${IPTABLES} -t nat -P PREROUTING ACCEPT
     ${IPTABLES} -t nat -P POSTROUTING ACCEPT
     ${IPTABLES} -t nat -P OUTPUT ACCEPT
   elif [ $table = mangle ]; then
     ${IPTABLES} -t mangle -P PREROUTING ACCEPT
     ${IPTABLES} -t mangle -P INPUT ACCEPT
     ${IPTABLES} -t mangle -P FORWARD ACCEPT
     ${IPTABLES} -t mangle -P OUTPUT ACCEPT
     ${IPTABLES} -t mangle -P POSTROUTING ACCEPT
   elif [ $table = filter ]; then
     ${IPTABLES} -t filter -P INPUT ACCEPT
     ${IPTABLES} -t filter -P FORWARD ACCEPT
     ${IPTABLES} -t filter -P OUTPUT ACCEPT
   fi
 done
fi
return 0
}

case "$1" in
start)
log_begin_msg "Loading iptables settings..."
${IPTABLES}-restore ${SAVE_RESTORE_OPTIONS} ${IPTABLES_SAVE}
log_end_msg $?
;;
save)
log_begin_msg "Saving iptables settings..."
${IPTABLES}-save ${SAVE_RESTORE_OPTIONS} > ${IPTABLES_SAVE}
log_end_msg $?
;;
stop)
log_begin_msg "Clearing iptables settings..."
flush
log_end_msg $?
;;
restart)
$0 stop
$0 start
;;
status)
${IPTABLES} -L
;;
*)
log_success_msg "Usage: $0 {start|stop|restart|status|save}"
exit 1
esac

and another one to /etc/default/iptables :

IPTABLES_SAVE="/etc/iptables-rules"
SAVE_RESTORE_OPTIONS="-c"

finally, once you are satisfied with your actual rules, save them by typing the following:

# /etc/init.d/iptables save

We also need to make sure that the service will be started upon boot up by typing:

# update-rc.d iptables defaults 20

And that's it, here we are with a box that provide full access t internet!

4. Troubleshooting

Even though this tutorial is made in such a way that you could just copy and paste, issues may arise.

You might find useful to install the packages dnsutils, telnet, tcpdump and nmap to get a better idea of what is going on.

In /var/log , action is going to be mailly in messages, daemon.log and syslog.

In zone lan.debuntu.local, we define the standard bind headers and finally, some static hosts in our network: router, ns, dhcp and any other host to point to 192.168.2.1.

In zone 2.168.192.in-addr.arpa, we define our reverse lookup name for IP 192.168.2.1.

You need to make sure that the directory holding those db files is writable as bind will need to create journal files to get DDNS to work.

Finally, we just have to restart bind. If there is anything wrong, /var/log/syslog is your best friend, along with goolge :).

/etc/init.d/bind9 restart

now that our DNS server is up and running, we need to handle DHCP request.

Remote syslog logging on Debian and Ubuntu

2009-05-04T22:19:00.000-07:00

syslogd is the Linux system logging utility that take care of filling up your files in /var/log when it is asked to.

On a standard system, logging is only done on the local drive. But syslog can be configured to receive logging from a remote client, or to send logging to a remote syslog server.

Some of the use cases could be:

A machine which filesystem goes read-only
Log replication

this tutorial will explain how to set up both the server, to receive message from a remote client, and the client to emit messages to a syslogd server.

In this tutorial I will consider that you do not have any firewalls interfering with the traffic.
The syslogd server will be called etch32 and has IP 192.168.2.1.
The client is called hardy32-1. Its IP do not matter.

syslogd is using UDP on port 514

1. Setting up the syslogd server

The distribution used for the server is, as its hostname says, a Debian Etch. But, unless you are not using a debian based distro, the changes will be the same.

changes for syslogd are pretty minor. We basically simply have to tell syslogd to listen for remote messages.
It is either opened or closed, there is no filtering, so if you need to only accept a subset of machines, IPtables will be your friend.

To enable remote logging, go and edit /etc/default/syslogd and make sure SYSLOGD is set to:

SYSLOGD="-r"

then, restart syslogd:

# /etc/init.d/syslogd restart

Now, let set a client to send messages to our remote syslogd server.

2. syslogd clients

The action is in /etc/syslog.conf. In this example, I am going to send to both the remote syslogd server and to the filesystem the messages written to /var/log/messages.

In Ubuntu, this is the bit of conf that handle that:

*.=info;*.=notice;*.=warn;\
auth,authpriv.none;\
cron,daemon.none;\
mail,news.none -/var/log/messages

The default is to send the messages to /var/log/messages without "synching" after each log messages ("-" in front of the file name.).

to specify a remote host, the name or the ip of the remote host as to be given instead of a file, and, prepended with an "@". So, to send the messages writtent to /var/log/messages, our syslog.conf file will look like:

*.=info;*.=notice;*.=warn;\
auth,authpriv.none;\
cron,daemon.none;\
mail,news.none -/var/log/messages
*.=info;*.=notice;*.=warn;\
auth,authpriv.none;\
cron,daemon.none;\
mail,news.none @etch32

to have etch32 receiving messages from hardy32-1.

now, we need to make syslog aware of the chances:

$ sudo /etc/init.d/sysklogd restart

3. What happens then

Well, lets take a look at each /var/log/messages after I restarted syslogd on hardy32-1 and I started tcpdump on eth0:

Jun 30 23:01:59 etch32 dhcpd: added reverse map from 198.2.168.192.in-addr.arpa. to hardy32-1.lan.debuntu.local
Jun 30 23:01:59 etch32 dhcpd: DHCPREQUEST for 192.168.2.198 (192.168.2.1) from 00:0c:29:d4:01:57 (hardy32-1) via eth1
Jun 30 23:01:59 etch32 dhcpd: DHCPACK on 192.168.2.198 to 00:0c:29:d4:01:57 (hardy32-1) via eth1
Jun 30 23:04:15 hardy32-1.lan.debuntu.local syslogd 1.5.0#1ubuntu1: restart.
Jun 30 23:05:01 hardy32-1.lan.debuntu.local kernel: [ 6268.923820] device eth0 entered promiscuous mode
Jun 30 23:05:01 hardy32-1.lan.debuntu.local kernel: [ 6268.923847] audit(1214863498.177:3): dev=eth0 prom=256 old_prom=0 auid=4294967295
Jun 30 23:05:11 hardy32-1.lan.debuntu.local kernel: [ 6278.677844] device eth0 left promiscuous mode
Jun 30 23:05:11 hardy32-1.lan.debuntu.local kernel: [ 6278.677869] audit(1214863510.404:4): dev=eth0 prom=0 old_prom=256 auid=4294967295

As you can see, messages from hardy32-1 contains the box FQDN: hardy32-1.lan.debuntu.local and we see that eth0 went temporarily in promiscuous mode.

Remote Access to the Ubuntu Linux Desktop

2009-05-02T11:06:00.000-07:00

Ubuntu Linux provides remote desktop access. This provides two extremely useful features. Firstly it enables you or another person to view and interact with your desktop environment from another computer system either on the same network or over the internet. This is useful if you need to work on your computer when you are away from your desk while traveling or sitting in a coffee shop. It is also useful in situations where a co-worker or IT support technician needs access to your desktop to resolve a problem.

Secondly, in addition to providing access to your primary desktop (the one you see when you switch on your monitor every morning) it also enables you to create multiple desktops and connect to them remotely.

The Ubuntu remote desktop functionality is based on technology called Virtual Network Computing (VNC) and in this chapter we will cover the key aspects of configuring and using remote desktops with Ubuntu Linux. It is important to note that there are both secure and insecure ways to access a remote desktop. Although both approaches will be covered, the secure method is strongly recommended when accessing remote desktops over an internet or other insecure connection.

Activating Remote Desktop Access

The first step in setting up remote desktop access is to activate it and define some basic security settings. These settings are configured in the Remote Desktop Preferences dialog. To access this dialog, open the desktop System menu, select Preferences and click on Remote Desktop. When selected the following window will appear:

The Remote Desktop Preferences dialog consists of two panels. The General settings panel is displayed by default and provides the following configuration options:

Allow others to view your desktop - Activates remote desktop access for viewing purposes.

Allow other users to control your desktop - Allows users accessing your remote desktop to control the desktop. In other words the remote user can do anything to your desktop that they want using their mouse and keyboard as if they were sitting physically at the local system. When this option is disabled, the remote user can see what is happening on the desktop, but is unable to interact with it using the keyboard and mouse.

Ask for confirmation - When selected, this option causes a dialog to appear warning you of an attempt by a remote user to connect and prompting you to confirm or deny the connection. If you are likely to want to log in remotely you will need to turn this off since you will not be at the local system to accept your own connection.

Require the user to enter this password - Specifies a password which must be entered by the remote user to access your desktop. It is strongly advised that you select this option and specify a password.

Finally this screen specifies the command to run on the remote system to access the desktop.

The Advanced configuration options are accessed by clicking on the Advanced tab. Once selected, the following panel will be displayed in the Remote Desktop Preferences dialog:

Details of the advanced configuration options are as follows:

Only allow local connections - Only allows remote desktop connections to be established from the local system. This essentially disables access from remote systems.

Use an alternate port - Remote Desktop access requires the use of a TCP/IP port. By default a port will be assigned to the current connection starting at port 5900. If an alternate port is required, select this option and specify the required port.

Disable the wallpaper when connected - A key objective of remote desktop access is to minimize the volume of network traffic involved in projecting the desktop to the remote user. If the desktop currently has a wallpaper image defined (in other words the background of the desktop) this will result in a considerable amount of additional network traffic. This option switches the desktop wallpaper to a plain background to reduce bandwidth usage thereby speeding the desktop presentation.

Require encryption - As previously mentioned, remote desktop access may be established using both secure and insecure mechanisms. When selected, this option enforces the use of secure, SSH based, connections when accessing the desktop remotely.

Lock screen on disconnect - Causes the desktop screen lock to be engaged automatically when the remote desktop connection is disconnected. This ensures that the next user to connect to the desktop will be required to enter a password to gain access.

Always display icon - Causes the remote desktop icon to appear in the Notification area of the top status bar when remote desktop access is enabled (even when a remote user is not connected).

Only display an icon when there someone is connected - Displays an icon on the Notification area of the top status bar when a user is remotely connected to the desktop.

Never display an icon - The Notification icon is never displayed regardless of the current state of the remote desktop system.

Once you have configured Remote Desktop access you are ready to try connecting.

Accessing a Remote Ubuntu Linux Desktop using Vinagre

As mentioned previously there are both secure and insecure methods for accessing a remote desktop. In this section we assume that the desktop is being accessed by a remote system on the same local network where security is not a concern. See the section later in this chapter for establishing a secure connection if you are connecting from a system outside your firewall.

Connection to the remote desktop may be performed by running either the vncviewer tool, or the newer vinagre on the system from which the remote desktop is to be accessed. On Ubuntu systems, vinagre is installed by default. On other systems, however, it may need to be manually installed. For example to install vinagre on a Fedora system, execute the following command in a terminal window:

su
yum install vinagre

To access a remote desktop, open a terminal window and enter the command specified in the Remote Desktop Preferences dialog, for example:

vinagre hostname:0

where hostname is either the hostname or IP address of the remote system.

If you configured the remote system to prompt to approve a connection a dialog will appear on the remote system. Until the connection is approved the vinagre session will wait. Once approved, or if no approval is required, vinagre will prompt for the password (assuming one was defined):

Enter the password and vinagre will appear containing the desktop from the remote system. If remote desktop control was enabled you can interact with the desktop as if you were sitting at the remote screen. The following figure illustrates a vinagre session running on a Fedora system attached to a remote desktop running on Ubuntu. Note that only part of the remote desktop is displayed. The entire desktop may be viewed by clicking on the Full Screen toolbar button.

Attaching to a Remote Desktop using vncviewer

Vinagre is a relatively new tool and has a number of advantages over the older vncviewer tool (such as the ability to manage concurrent connections to multiple remote desktops). For those who prefer to use a simpler interface, or who use a system for which vinagre is not easily obtainable, vncviewer makes an adequate alternative.

As with vinagre, vncviewer is not installed by default on many systems. To install vncviewer on Red Hat, CentOS and Fedora systems, execute the following commands in a terminal window:

su
yum install vnc

Similarly, to install vncviewer on an Ubuntu system:

sudo apt-get install xvnc4viewer

Once installed, run the command using the following syntax where hostname is the host name or IP address of the remote system and port is the port number assigned for access to the desktop:

vncviewer hostname:port

If the remote desktop was configured to require a password, vncviewer will prompt for this before displaying the desktop:

So far in this chapter we have assumed that the remote desktop was being accessed from a Linux or Unix system. Access is also possible from a Windows system.

Accessing a Remote Ubuntu Linux Desktop from a Windows System

In order to access a Linux remote desktop from a Windows system the first step is to install a Windows VNC client on the Windows system. There are a number of VNC packages available for Windows. In this chapter we will look at TightVNC (http://www.tightvnc.com).

Download and install TightVNC on your Windows system. Once installed, launch the TightVNC Viewer and in the resulting Connection details dialog enter the IP address or hostname of the remote system and press OK. Enter the password if one is required. The screen should load and display the remote desktop,

You may also enter the port number in the form hostname::5900 (screen 0 in VNC uses port 5900). TightVNC assumes port 5900 if none is specified but when we look at setting up additional desktops later in this chapter we will need to specify port numbers in order to connect.

Establishing a Secure Remote Desktop Session

The remote desktop configurations we have explored so far in this chapter are considered to be insecure because no encryption is used. This is acceptable when the remote connection does not extend outside of an internal network protected by a firewall perimeter. When a remote session is required over an internet connection a more secure option is needed. This is achieved by tunneling the remote desktop through a secure shell (SSH) connection.

Before a secure connection is established the SSH server must be installed on the system to which the connection is to be established. For detailed steps on installing the SSH server on an Ubuntu Linux system see Configuring Ubuntu Linux Remote Access using SSH.

Once the SSH server is installed and active it is time to move to the other system. At the other system, log in to the remote system using the following command, which will establish the secure tunnel between the two systems:

 ssh -L 5900:localhost:5900 hostname

In the above example, hostname is either the host name or IP address of the remote system. Log in using your account and password. The secure connection is now established and it is time to launch vncviewer so that it uses the secure tunnel. Leaving the ssh session running in the other terminal window, launch another terminal and enter the following command to use vncviewer:

vncviewer localhost::5900

Alternatively, to use vinagre:

vinagre localhost:5900

The vncviewer session will prompt for a password if one is required, and then launch the corresponding viewer providing secure access to your desktop environment.

If you are connecting to the remote desktop from outside the firewall keep in mind that the IP address for the ssh connection will be the external IP address provided by your ISP, not the LAN IP address of the remote system (since this IP address is not visible to those outside the firewall). You will also need to configure your firewall to forward port 22 (for the ssh connection) to the IP address of the system running the desktop. It is not necessary to forward port 5900. Steps to perform port forwarding differ between firewalls, so refer to the documentation for your firewall, router or wireless base station for details specific to your configuration.

Establishing a Secure Remote Desktop Session from a Windows System

A similar approach is taken to establishing a secure desktop session from a Windows system. Assuming that you have a VNC client installed (as described above) the one remaining requirement is a Windows ssh client. A popular ssh client for Windows is (PuTTY).

Once PuTTY is downloaded and installed the first step is to set up a secure connection between the Windows system and the remote Linux system with appropriate tunneling configured. When launched, PuTTY displays the following screen:

Enter the IP address or host name of the remote host (or the external IP address of the gateway if you are connecting from outside the firewall). The next step is to set up the tunnel. Click on the + next to SSH in the Category tree on the left hand side of the dialog and click on Tunnels. The screen should appear as follows:

Enter 5900 as the Source port and localhost:5900 as the Destination and click on Add. Finally return to the main screen by clicking on the Session category. Enter a name for the session in the Saved Sessions text field and press save. Click on Open to establish the connection. A terminal window will appear with the login prompt from the remote system. Enter your user login and password credentials.

The SSH connection is now established. Launch the TightVNC viewer and enter localhost::5900 in the VNC Server text field and click on Connect. The viewer will establish the connection, prompt for the password and then display the desktop. You are now accessing the remote desktop of a Linux system on Windows via a secure tunnel.

Creating Additional Desktops

In the examples so far we have only covered remote access to the primary desktop. By primary desktop we mean the desktop you see when you sit at your computer and turn on the monitor. While this is fine for a single user system we should not lose sight of the fact that Linux is a multi-user operating system and it will often be necessary for more than one person to have remote desktop access at a time. While it might be fun to watch everyone fight over the mouse pointer as they share the same desktop it is clear that not much work will get done. The solution to this is to run multiple desktops for the users to connect to.

New desktop environments are created using the vncserver utility. If vncserver is not already installed, it may be installed from a terminal window as follows:

sudo apt-get install vnc4server

Once the VNC server package is installed, the next step is to assign a password to protect the desktops. This can be achieved using the vncpasswd tool. Run this tool from the command-line prompt in a terminal window and enter the password of your choice.

The desktop we have used so far in this chapter is desktop :0. New desktops must be assigned different numbers. For example to launch desktop :1 run the following command from a terminal window command-line prompt:

vncserver :1

This will start a new desktop in the background ready for a remote user to connect to. To connect to the desktop follow the steps for connecting to desktop :0 outlined above but this time use port 5901 instead of port 5900 (you will similarly use port 5902 for desktop :2 and so on).

When the desktop appears you will notice that it doesn't look much like the standard desktop:

The problem here is that we need to configure the VNC session to launch the correct desktop. To do this shutdown the VNC desktop session as follows:

vncserver -kill :1

Next go to your home folder and edit the $HOME/.vnc/xstartup file. This will look similar to the following file:

#!/bin/sh

# Uncomment the following two lines for normal desktop:
# unset SESSION_MANAGER
# exec /etc/X11/xinit/xinitrc

[ -x /etc/vnc/xstartup ] && exec /etc/vnc/xstartup
[ -r $HOME/.Xresources ] && xrdb $HOME/.Xresources
xsetroot -solid grey
vncconfig -iconic &
xterm -geometry 80x24+10+10 -ls -title "$VNCDESKTOP Desktop" &
twm &

To configure this startup script to launch the standard desktop (known as the GNOME desktop) change the twm& line so that the file reads:

#!/bin/sh

# Uncomment the following two lines for normal desktop:
# unset SESSION_MANAGER
# exec /etc/X11/xinit/xinitrc

#[ -x /etc/vnc/xstartup ] && exec /etc/vnc/xstartup
#[ -r $HOME/.Xresources ] && xrdb $HOME/.Xresources
#xsetroot -solid grey
#vncconfig -iconic &
#xterm -geometry 80x24+10+10 -ls -title "$VNCDESKTOP Desktop" &

unset SESSION_MANAGER
sh /etc/X11/xinit/xinitrc

Restart the vncserver:

vncserver :1

Finally, reconnect from the remote system. The full desktop should now appear in the vncviewer or vinagre window.

Enable remote desktop on linux using VNC

2009-05-02T11:02:00.000-07:00

Introduction

As an Windows administrator, I always have to work with many Windows servers. Most of the time, I use remote access rather than go to in front of each server. This can be done easily because they’re the same platform. But sometime I also need to access Linux server from Windows XP, too. This can be done by using VNC. By default, VNC is alrealy installed on Redhat so I only need to configure it as VNC server and I have to install VNC Viewer on Windows XP. When enable this service, please keep in my that others can also remote to the server with this protocol, too!. So if your network can’t be trusted, do not enable the vncserver service. But in my case, I have firewall to limit only from my computer and the network is trusted.

VNC stands for Virtual Network Computing. It is remote support software which allows you to view and fully interact with one computer desktop (the “VNC server”) using a simple program (the “VNC viewer”) on another computer desktop anywhere on the Internet. The two computers don’t even have to be the same type, so for example you can use VNC to view a Windows Vista desktop at the office on a Linux or Mac computer at home. For ultimate simplicity, there is even a Java viewer, so that any desktop can be controlled remotely from within a browser without having to install software.

Step-by-step

In this section, I’ll show how to configure VNC server on Redhat server and using VNC Viewer connect the server remotely from Windows XP.

On Redhat server, login with your username that you want to enable remote access. In this example, I will use ‘admin’ user.
Open Terminal, type ‘vncpasswd’. Type your password and verify password again. This command will use to set you password for remote access for the current user.
Before next step, you need to logged on as root by type ’su root’.
Edit the file /etc/sysconfig/vncservers by type ‘ vi /etc/sysconfig/vncservers’.
Note: If you are new to Linux, vi is an editor tool in command line mode on Linux.
You’ll see text file as in the figure below. Next, I’ll edit on the highlight line.
Uncomment on the highlight line. If you have more than one usernames that want to enable remote acces, you can change VNCSERVERS value in this format, “1:username1 2:username2 3:username3 ….”. In this example, I have only one user which is root so this line of mine is ‘VNCSERVERS = “1:admin”‘.
Now save the file and exit. To save file, hold ESC + ‘:’ and type ‘wq’ to write and quit file.
Next, log off the user if you are not user ‘root’ and log in as root. Enable VNC service by type ‘chkconfig vncserver on’. Then, start the VNC service by type ’service vncserver start’.
If you have firewall enable on Redhat, be sure that your firewall configuration won’t block connection from remote computer by open port TCP 5901 for remote access. Open Applications -> System Settings -> Security Level. Add ‘5901:tcp’ on Other ports.
Note: VNC uses TCP protocol on port 5901.
Now you can connect Redhat server from remote computer. On my Windows XP computer, open VNC Viewer on Windows XP, type IP Address of Redhat server with number as a username specify in step 6. In this example, I want to remote to Redhat server as ‘admin’ user which I assign as number 1 in step 6 (1:admin) and my Redhat server is 10.110.141.220. So I type ‘10.110.141.220:1′.
Note: You can download VNC Viewer for free at realvnc.com
Type your password for ‘admin’ user which has been assign in step 2.
Now you have connect to Redhat server remotely. But you’ll see that the interface looks different. You have to do a little thing more.
On Redhat server, open terminal and type ‘vi /home/username/.vnc/xstartup’. In this example, I type ‘vi /home/admin/.vnc/xstartup’.
Note: If you going to enable remote access for user ‘root’, the file would be at ‘/root/.vnc/xstartup’.
Uncomment these two lines and save the file.
Note: If you want to force to load Gnome or KDE Desktop on remote access, edit the last line from ‘twm &’ to ’startx &’ for Gnome and ’startkde &’ for KDE Desktop.
Type ’service vncserver restart’ to apply changes.
Reconnect using VNC viewer on remote computer again. Now you will see the desktop as you were log in at the server but now you’re remotely :).

Run Windows and Linux without virtualization

2009-05-02T10:46:00.000-07:00

Linux does everything that many users want it to, but some people have tasks that require Windows applications. You can dual-boot both operating systems, or run Windows in a virtualized environment on Linux. Alas, virtualization makes the guest OS almost useless for processor- and RAM-intensive tasks like editing videos and playing games. Now, a Ubuntu-based distro called andLinux takes cooperation with Windows to a whole new level.

The miracle ingredient in andLinux is its coLinux kernel. The coLinux project takes a stable release of the Linux kernel and ports it to run on Windows. That means that, unlike virtualization software, andLinux installs on Windows like any other application.

But there's more to andLinux than just sticking the coLinux kernel in a stock Ubuntu. According to Joachim Gehweiler, one of the developers of andLinux, the project also had to roll in the Xming X server and PulseAudio sound server and make sure these components work together.

andLinux is available in two flavours -- a 665MB version that uses KDE and takes up 4.5GB of disk space, and a lightweight 143MB version with Xfce that uses 2.5GB on a hard drive. The developers recommend earmarking at least 192MB of RAM during installation for andLinux, but make sure you have enough memory left for Windows itself. andLinux will run only on 32-bit versions of Windows 2000, XP, 2003, and Vista, and your hard drive needs to be formatted using the NTFS filesystem.

Click to enlarge Both versions of andLinux are distributed as Windows executable files, and launch the easy-to-use andLinux graphical installer. The installer asks questions to help it bridge the gap between Windows and Linux. For example, to access your Windows files from andLinux you have the option to either use Samba or COFS (coLinux File System). While COFS is easy to configure, the andLinux installer advises you to use Samba if you have filenames with special characters. To further enhance the co-existing experience, andLinux lets users configure file type associations, and decide which Linux applications to add to the Windows "Open With" menu.

The installer performs several behind-the-scenes configuration tasks, such as setting up the TAP-coLinux network adapter for sharing the network connection with Windows. Most of these tasks are performed by the Inno setup scripts on the Windows side, but some, such as Samba setup, have to be done from the Linux side, and are performed by bash and Perl scripts written by the andLinux developers.

The installer also creates an andLinux start menu entry and quick launch icon. andLinux installs as a Windows service and can start automatically when the computer boots, though depending on your hardware this could slow down your Windows boot process. You can also launch andLinux manually at a command prompt, but there's no shortcut on the desktop or a quick launch icon you can click to start andLinux.

I run andLinux on two dual-core boxes -- an E4400 2.0GHz machine with 2GB of RAM, and an E6300 1.8GHz with 1GB of RAM. On both machines starting andLinux as a service doesn't cause any visible stress, just disk activity after Windows boots, indicating andLinux starting up in the background. On a slower 1.7GHz Celeron laptop with 1GB RAM, I see a steep increase in application launch times while andLinux boots in the background, but things get back to normal once andLinux's up and running. That's an improvement on the laptop's performance when running a virtual machine, during which time it crawls to a halt.

The loaded Intel dual-core boxes are optimized to run virtualized software thanks to Intel Virtualization Technology, but andLinux doesn't have any hardware-specific optimizations. The developers say you will benefit from virtualization threads only when running one Linux application concurrently with at least one Windows application. But this advantage is negated when you run two (or more) Linux applications, as all such apps are treated as one Windows process.

andLinux creates a 4GB virtual partition out of a portion of the partition it's installed in in which it keeps its binaries, and shares a small part of the Windows file system via Samba or COFS depending on the method you chose during setup. You can keep files you create using andLinux applications on either the virtual partition or the Windows file system.

At first, you may feel andLinux is a bloated way of running Linux apps that have Windows versions as well, such as AbiWord, the GIMP, and Firefox. Since they run atop the Windows desktop, you don't see the Xfce or the KDE desktops. But as you continue exploring you'll notice Konqueror and its KIO slaves and a bunch of KDE utilities and games that have never run on a Windows desktop before.

When it comes to remote sharing, you can configure andLinux to let you SSH into it from another machine. You can also remote share your Windows desktop via VNC or rdesktop and implicitly remote share andLinux.

To further drive home the point that you are really running a Linux distro, there's the command-line apt-get and the graphical Synaptic utilities configured for installing additional applications from Ubuntu's repositories. I tried some applications from the repository (including OpenOffice.org, Pidgin, AbiWord, XChat, and Thunderbird) and they all worked. You can also install new apps by compiling them from source.

But you are not only running a Linux distro in Windows; you're running one alongside the other. To experience the cooperative nature of andLinux and Windows, you can right-click on a .txt document and open and edit it in Kate, read a .pdf in KPDF, and copy and paste text between a Windows app and a Linux one.

What you won't be able to do is play 3-D games, such as Alien Arena or Torcs. Nor will you be able to use your TV tuner card to watch videos on Linux with MythTV, or use your Bluetooth devices, even though some TV tuners and many USB bluetooth dongles work on all major natively-installed Linux distros.

On the plus side, you can share your printer between Windows and andLinux, thanks to recently acquired printing support. Printing support is expected to be included in the next release so you'll be saved the effort of setting it up manually.

Running atop Windows has one final disadvantage. andLinux lacks security support for multi-user environments and can be run by all Windows users that have access to the computer.

For a desktop user, andLinux is a productive method of running Linux and Windows together. It doesn't focus on segregating Windows and Linux as host and guest OS. Instead of merely coexisting it allows the two OSes to cooperate, resulting in the welcome ability to share files between the two OSes and open files using apps on either OS. It's still slower than a pure Linux installation, but it runs smoothly as compared to Linux running on an emulated PC, especially on older and slower hardware.

All said and done, andLinux's limitations aren't any greater than those of a virtualized environment, and in its current form, neither are its advantages. But I'd still recommend it to desktop users, due to its non-existent learning curve and for taking Linux-Windows interoperability to a whole new level.

Ten reasons why Linux will triumph over Windows

2009-05-02T10:40:00.000-07:00

1: Inconsistent Windows releases

One of the things you can always count on from Microsoft is that you can’t count on its new operating systems to be reliable. Let’s take a look at the individual releases:

Windows 95: Revolutionized personal computing.
Windows 98: Attempted to improve on Windows 95; failed miserably.
Windows Me: A joke, plain and simple.
Windows NT: Attempted to bring enterprise-level seriousness to the operating system; would have succeeded had it not taken Steven Hawking-like intelligence to get it working.
Windows XP: Brought life back to the failing Windows operating system. It hadn’t been since Windows 95 that the operating system was this simple.
Windows Vista: See Windows Me.

With this in mind, what do we expect from Windows 7? Myself, not much.

2: Consistent Linux releases

Converse to number 1, you have the far more consistent releases of the various Linux distributions. Yes, there have been a few dips along the way (Fedora 9 being one of them). But for the most part, the climb for Linux has been steadily upward. Nearly every Linux distribution has improved with age. And this improvement isn’t limited to the kernel. Look at how desktops, end-user software, servers, security, admin tools, etc., have all improved over time. Once could easily argue that KDE 4 is an example of a sharp decrease in improvement. However, if you look at how quickly KDE 4 has improved from 4.0 to 4.3 you can see nothing but gains. This holds true with applications and systems across the board with Linux.

3. Continuing Windows price hikes

Recently, I have had a number of long-time Microsoft administrators asking my advice on solid replacements for Exchange. The reason? Microsoft changed its licensing for Exchange to a per-user seat. Now anyone who logs on to an Exchange server must have a license. You have 100 employees (including administrators) who need to log on to Exchange? Pony up! This gets serious when your company starts having to cough up the money for 500+ Exchange licenses. The very idea that Microsoft would make such a bold change to licenses is made even more ridiculous considering the current state of the economy. Companies worldwide are having to scale back. And like Exxon Mobile celebrating record profits amid the catastrophe known as Hurricane Katrina, Microsoft creating such a cost barrier while the globe is facing serious recession is irresponsible and reprehensible.

4. Stable Linux “prices”

Converse to number 3, the prices of open source software licenses have remained the same — $0.00. When those administrators come to me asking for open source replacements for Exchange I point them to eGroupware and Open-X-Change. Both are outstanding groupware tools that offer an even larger feature set than their Microsoft equivalent. Both are reliable, scalable, secure, and free. The only cost you will have with either is the hardware they are installed upon. And with both packages, there is no limit to the amount of users that can be set up. One user, 1,000 users — it’s all good with open source software.

5: Windows hardware incompatibility

Microsoft Vista was a nightmare when it came to hardware compatibility. Not only was Vista incompatible with numerous peripherals, it took supercomputer-level iron to run the operating system! Sure this was a boon to Intel, which stood to make a pretty shiny penny. Intel knew a good amount of the public would be shelling out for new hardware, and the new hardware would cost more because it had to be faster to run Vista in all its Aero glory. But even hardware that would run nearly any other OS with lightening-fast speed was brought to a slow, grinding halt with Vista.

6: Linux hardware compatibility

Converse to number 5, Linux continues to advance in the category of hardware compatibility. Take Xorg, for example. Recent developments with the star of Linux’ graphical desktops have the X Windows server running sans xorg.conf. This was done primarily because the system had grown so good at detecting hardware. And so long as there wasn’t a cheap KVM between your monitor and your PC, Xorg would easily find the mode for your display and run X properly. With new distributions (such as Fedora 10), X configuration is becoming a thing of the past. Most other pieces of hardware are finding the same level of recognition.

7: Windows promises

I wanted to save this for last, but seeing as how it is number 7… We’ve all heard the pundits proclaiming Windows 7 will be the resurrection of the Microsoft operating system. But I recall this same proclamation with nearly every release from Redmond. Windows Vista was going to revolutionize the way the user interfaced with the computer. Vista was going to be the operating system you would never notice. Instead, Vista refused to NOT let you notice. And Windows Me was going to take Windows 98 and make it far more simple for the average user. What did it really do? Remove nearly every actual functioning system in the operating system, leaving little more than a browser and an e-mail client.

Everyone is always fond of saying the next Windows release will redefine the personal computer. But the public has finally reached such a point of apathy for Microsoft’s up and coming, the majority doesn’t even realize something new is coming out. The media can continue to push Windows 7, but the public will continue using XP until Microsoft pries it from its cold, dead fingers. And of course no one really knows when Windows 7 will land. How many dates Microsoft announces vs. how many dates change will probably be a 1:1 ratio.

8: Linux transparency

Converse to 7… The next release of any Linux distribution is never shrouded in mystery. Because of the nature of open source, the release candidates are always available to the public (and not on a limited basis), and the timeline is always made available. Any user can know exactly when a feature-freeze happens for a release of any distribution. And all Linux distributions work under the “full disclosure” model. Because of this, there is little false advertising going on with Linux. And unlike with Microsoft, you will never hear of a distribution claiming that its next release will revolutionize computing. If you go to the Fedora Project Wiki, you can view all the proposed and accepted features that will be included in the next release. You can also view the completed release schedule, where you will see that Fedora 11 has set an alpha release of 02/03/09, a beta release of 03/24/09, and a final release of 05/26/09. These dates are fairly firm and almost always on target.

9: Feature comparison

Let’s compare the feature lists of Windows 7 and Fedora 11.

Windows 7: OS X-like Doc, Multi-touch screen, mapping application similar to Google Earth, Hyper-Visor virtualization, location-aware apps, User Access Control improvements, Sidebar removal.
Fedora 11: 20-second boot time, btrfs file system, Better C++ support, Cups PolicyKit integration, DNS Security (DNS SECurity), ext4 default file system, Fingerprint reader integration, IBUS input method replaces SCIM (to overcome limitations), GNOME 2.26, KDE 4.2, Windows cross-compiler inclusion.

If you look at those features in and of themselves, you could easily argue that either one could be the more impressive list (depends upon your bias). But understand that the Fedora 11 features are added on an already outstanding operating system, whereas the Windows 7 features are being added to a lesser operating system. And what Microsoft is proclaiming to be the biggest improvement (multi-touch) doesn’t actually improve the operating system and also requires, surprise, new hardware! To get the most out of Fedora 11, you’ll be good to go with what you already have.

10: Hardware requirements

Vista-lite? Out of the mouths of Microsoft comes the proclamation that Windows 7 will run on any hardware that would run Vista and even slightly less powerful hardware. Slightly less powerful? What exactly does that mean? Well for one, Windows 7 will have no luck in the netbook market. And since XP is dying, the netbook market will be owned by Linux. Netbooks are not gaining enough power to run anything from Windows but the watered-down version of XP. Netbooks are not going anywhere, and consumers (both home and corporate) have their limits on how many hardware upgrades they will make to fulfill an operating systems’ needs. As of Fedora 10, the minimum system requirements look like something out of the mid ’90s.

Surf the Web Carefully - Use Proxy Server!

2009-05-01T09:51:00.000-07:00

Sweet dreams, Big Brother... I'm using Proxy! Whoever you are, privacy is your right!

Learn howto protect your privacy and surf the web carefully - Use Proxy server.

Proxy Servers

A proxy server is a kind of buffer between your computer and the Internet resources you are accessing. They accumulate and save files that are most often requested by thousands of Internet users in a special database, called “cache”. Therefore, proxy servers are able to increase the speed of your connection to the Internet. The cache of a proxy server may already contain information you need by the time of your request, making it possible for the proxy to deliver it immediately. The overall increase in performance may be very high. Also, proxy servers can help in cases when some owners of the Internet resources impose some restrictions on users from certain countries or geographical regions. In addition to that, among proxy servers there are so called anonymous proxy servers that hide your IP address thereby saving you from vulnerabilities concerned with it.

Anonymous Proxy Servers

Anonymous proxy servers hide your IP address and thereby prevent unauthorized access to your computer through the Internet. They do not provide anyone with your IP address and effectively hide any information about you and your reading interests. Besides that, they don’t even let anyone know that you are surfing through a proxy server. Anonymous proxy servers can be used for all kinds of Web-services, such as Web-Mail (MSN Hot Mail, Yahoo mail), web-chat rooms, FTP archives, etc.

Why Should You Use Anonymous Proxy Servers?

Any web resource you access can gather personal information about you through your unique IP address – your ID in the Internet. They can monitor your reading interests, spy upon you and, according to some policies of the Internet resources, deny accessing any information you might need.

You might become a target for many marketers and advertising agencies who, having information about your interests and knowing your IP address as well as your e-mail, will be able to send you regularly their spam and junk e-mails.

A web site can automatically exploit security holes in your system using not-very-complex, ready-made, free hacking programs. Some of such programs may just hang your machine, making you reboot it, but other, more powerful ones, can get access to the content of your hard drive or RAM. Everything a web site may need for that is only your IP address and some information about your operating system.

Using an anonymous proxy server you don't give anybody any chance to find out your IP address and any information about you and use them in their own interests.

The Solution

Using an anonymous proxy server you don’t give anybody chance to find out your IP address to use it in their own interests. We can offer you three ways to solve your IP problem:

1. Secure Tunnel - pay proxy server with plenty of features. Effective for personal use, when your Internet activities are not involved in web site development, mass form submitting, etc. The best solution for most of Internet users. Ultimate protection of privacy - nobody can find out where you are engaged in surfing. Blocks all methods of tracking. Provides an encrypted connection for all forms of web browsing, including http, news, mail, and the especially vulnerable IRC and ICQ. Comes with special totally preconfigured software.

2. ProxyWay Pro - multifunctional anonymous proxy surfing software which you can use together with a wide variety of web applications (web browsers, Instant Messengers, Internet Relay Chat (IRC), etc.) to ensure your anonymity. ProxyWay Pro provides an extended proxy management system that enables you to search for, check proxy (multithreaded proxies checking), analyze, validate proxy servers for speed, anonymity, type (HTTP/HTTPS/SOCKS), geographical location, create proxy chains. Allows update proxy list automatically using scheduler. ProxyWay Pro lets you clear history, block ads and popups, change User-Agent and Referrer fields, block harm code and much more. Also it can be used as a simple local proxy server.

3. Here's small proxy list and this is also a good place to start with if you are a novice.

Port

Type

Country

Last Test

77.70.140.2	8080	anonymous		2009-05-01
193.37.152.236	3128	anonymous	Germany	2009-05-01
87.101.95.14	3128	anonymous	Greece	2009-05-01
80.80.111.133	3128	anonymous	Russian Federation	2009-05-01
67.205.102.88	80	anonymous		2009-05-01
216.161.86.10	8080	anonymous	United States	2009-05-01
67.69.254.240	80	anonymous	Canada	2009-05-01
85.15.233.46	8080	anonymous	Latvia	2009-05-01
212.117.162.229	3128	anonymous	Luxembourg	2009-05-01
61.135.147.172	80	anonymous	China	2009-05-01
217.10.246.4	8080	anonymous	Bulgaria	2009-05-01
67.69.254.255	80	anonymous	Canada	2009-05-01
88.191.60.196	3128	anonymous	France	2009-05-01
62.150.26.55	80	anonymous	Kuwait	2009-05-01
87.106.70.19	3128	anonymous	Germany	2009-05-01
203.189.116.27	8080	anonymous		2009-05-01
94.23.52.118	8080	anonymous		2009-05-01
83.2.212.9	8080	anonymous	Poland	2009-05-01
61.144.24.106	3128	anonymous	China	2009-05-01
159.148.82.3	3128	anonymous	Latvia	2009-05-01
200.174.85.195	3128	transparent	Brazil	2009-05-01
212.11.206.2	80	anonymous		2009-05-01
67.69.254.242	80	anonymous	Canada	2009-05-01
122.224.171.91	3128	anonymous	China	2009-05-01
118.98.18.138	8000	anonymous	Indonesia	2009-05-01
203.162.183.222	80	transparent	Vietnam	2009-05-01
80.93.90.96	3128	anonymous	France	2009-05-01
67.69.254.247	80	anonymous	Canada	2009-05-01
194.160.76.5	80	anonymous	Slovak Republic	2009-05-01
200.68.76.115	8080	anonymous	Argentina	2009-05-01
82.206.129.160	3128	anonymous	Chad	2009-05-01
150.176.182.33	80	high anonymity	United States	2009-05-01
221.226.3.141	3128	anonymous	China	2009-05-01
86.105.181.238	3128	anonymous	Romania	2009-05-01
125.65.165.178	80	anonymous	China	2009-05-01
202.206.100.39	3128	anonymous	China	2009-05-01
212.96.165.178	3128	anonymous	Czech Republic	2009-05-01
200.210.59.130	3128	anonymous	Brazil	2009-05-01
207.245.247.196	80	anonymous	Canada	2009-05-01
203.158.167.152	8080	anonymous	Thailand	2009-05-01
87.236.195.86	3128	anonymous	Czech Republic	2009-05-01
95.84.155.131	8080	high anonymity		2009-05-01
94.255.176.245	8080	anonymous		2009-05-01
67.69.254.253	80	anonymous	Canada	2009-05-01

202.98.23.116	80	anonymous	China	2009-05-01
87.120.58.65	8080	anonymous	Bulgaria	2009-05-01
88.249.214.159	3128	anonymous	Turkey	2009-05-01
58.27.140.58	8080	anonymous	Pakistan	2009-05-01
59.120.47.230	3128	anonymous	Taiwan	2009-05-01
204.16.1.182	3128	anonymous	United States	2009-05-01
210.51.33.43	80	transparent	China	2009-05-01
67.69.254.252	80	anonymous	Canada	2009-05-01
204.16.1.183	3128	anonymous	United States	2009-05-01
67.69.254.243	80	anonymous	Canada	2009-05-01
200.65.129.2	80	anonymous	Mexico	2009-05-01
222.73.17.198	80	anonymous	China	2009-05-01
67.69.254.250	80	anonymous	Canada	2009-05-01
94.40.22.170	80	anonymous		2009-05-01
77.240.82.6	80	anonymous	Saudi Arabia	2009-05-01
201.27.6.67	8080	anonymous	Brazil	2009-05-01
209.191.82.40	80	anonymous	United States	2009-05-01
189.18.245.64	8080	anonymous	Brazil	2009-05-01
213.180.131.135	80	anonymous	Poland	2009-05-01
67.69.254.248	80	anonymous	Canada	2009-05-01
203.123.12.139	8080	anonymous	Singapore	2009-05-01
140.127.81.86	80	anonymous	Taiwan	2009-05-01
62.176.173.241	3128	anonymous	Slovak Republic	2009-05-01
88.191.59.182	3128	anonymous	France	2009-05-01
63.209.154.10	3128	anonymous	United States	2009-05-01
86.101.185.97	8080	anonymous	Hungary	2009-05-01
20.132.16.22	80	anonymous	United States	2009-05-01
94.52.83.125	80	anonymous		2009-05-01
64.66.192.61	80	anonymous	United States	2009-05-01
217.218.56.200	8000	anonymous	Iran	2009-05-01
202.54.61.101	8080	high anonymity	India	2009-05-01
208.217.108.207	80	anonymous	United States	2009-05-01
221.214.213.37	8080	anonymous	China	2009-05-01
195.209.224.91	3128	anonymous	Russian Federation	2009-05-01
86.101.185.98	8080	anonymous	Hungary	2009-05-01
85.15.232.3	8080	anonymous	Latvia	2009-05-01
62.204.141.98	8000	anonymous	Bulgaria	2009-05-01
123.234.32.27	8080	anonymous	China	2009-05-01
61.188.38.30	80	anonymous	China	2009-05-01
118.228.148.83	80	high anonymity	China	2009-05-01
63.240.26.232	80	anonymous	United States	2009-05-01
222.124.201.71	3128	anonymous	Indonesia	2009-05-01
67.69.254.245	80	anonymous	Canada	2009-05-01
85.15.233.1	8080	anonymous	Latvia	2009-05-01
193.37.152.154	3128	anonymous	Germany	2009-05-01

Use ARIN WHOIS Database Search - identifies the owner and the IP address of the domain i.e. provides useful information to find Who is Behind an IP Address.

For example, if you want to know about owner of the IP address '203.162.183.222', you query about this IP on ARIN WHOIS Database Search site, it will provide you detail information about this IP.

Here's a search test URL: http://ws.arin.net/whois/?queryinput=203.162.183.222

Happy Protect Web Surfing! :)

Lazy Linux: 10 essential tricks for admins

2009-04-30T06:38:00.000-07:00

Learn these 10 tricks and you'll be the most powerful Linux systems administrator in the universe...well, maybe not the universe, but you will need these tips to play in the big leagues. Learn about SSH tunnels, VNC, password recovery, console spying, and more. Examples accompany each trick, so you can duplicate them on your own systems.

The best systems administrators are set apart by their efficiency. And if an efficient systems administrator can do a task in 10 minutes that would take another mortal two hours to complete, then the efficient systems administrator should be rewarded (paid more) because the company is saving time, and time is money, right?

The trick is to prove your efficiency to management. While I won't attempt to cover that trick in this article, I will give you 10 essential gems from the lazy admin's bag of tricks. These tips will save you time—and even if you don't get paid more money to be more efficient, you'll at least have more time to play Halo.

Trick 1: Unmounting the unresponsive DVD drive

The newbie states that when he pushes the Eject button on the DVD drive of a server running a certain Redmond-based operating system, it will eject immediately. He then complains that, in most enterprise Linux servers, if a process is running in that directory, then the ejection won't happen. For too long as a Linux administrator, I would reboot the machine and get my disk on the bounce if I couldn't figure out what was running and why it wouldn't release the DVD drive. But this is ineffective.

Here's how you find the process that holds your DVD drive and eject it to your heart's content: First, simulate it. Stick a disk in your DVD drive, open up a terminal, and mount the DVD drive:

# mount /media/cdrom # cd /media/cdrom # while [ 1 ]; do echo "All your drives are belong to us!"; sleep 30; done

Now open up a second terminal and try to eject the DVD drive:

# eject

You'll get a message like:

umount: /media/cdrom: device is busy

Before you free it, let's find out who is using it.

# fuser /media/cdrom

You see the process was running and, indeed, it is our fault we can not eject the disk.

Now, if you are root, you can exercise your godlike powers and kill processes:

# fuser -k /media/cdrom

Boom! Just like that, freedom. Now solemnly unmount the drive:

# eject

fuser is good.

Trick 2: Getting your screen back when it's hosed

Try this:

# cat /bin/cat

Behold! Your terminal looks like garbage. Everything you type looks like you're looking into the Matrix. What do you do?

You type reset. But wait you say, typing reset is too close to typing reboot or shutdown. Your palms start to sweat—especially if you are doing this on a production machine.

Rest assured: You can do it with the confidence that no machine will be rebooted. Go ahead, do it:

# reset

Now your screen is back to normal. This is much better than closing the window and then logging in again, especially if you just went through five machines to SSH to this machine.

Trick 3: Collaboration with screen

David, the high-maintenance user from product engineering, calls: "I need you to help me understand why I can't compile supercode.c on these new machines you deployed."

"Fine," you say. "What machine are you on?"

David responds: " Posh." (Yes, this fictional company has named its five production servers in honor of the Spice Girls.) OK, you say. You exercise your godlike root powers and on another machine become David:

# su - david

Then you go over to posh:

# ssh posh

Once you are there, you run:

# screen -S foo

Then you holler at David:

"Hey David, run the following command on your terminal: # screen -x foo."

This will cause your and David's sessions to be joined together in the holy Linux shell. You can type or he can type, but you'll both see what the other is doing. This saves you from walking to the other floor and lets you both have equal control. The benefit is that David can watch your troubleshooting skills and see exactly how you solve problems.

At last you both see what the problem is: David's compile script hard-coded an old directory that does not exist on this new server. You mount it, recompile, solve the problem, and David goes back to work. You then go back to whatever lazy activity you were doing before.

The one caveat to this trick is that you both need to be logged in as the same user. Other cool things you can do with the screen command include having multiple windows and split screens. Read the man pages for more on that.

But I'll give you one last tip while you're in your screen session. To detach from it and leave it open, type: Ctrl-A D . (I mean, hold down the Ctrl key and strike the A key. Then push the D key.)

You can then reattach by running the screen -x foo command again.

Trick 4: Getting back the root password

You forgot your root password. Nice work. Now you'll just have to reinstall the entire machine. Sadly enough, I've seen more than a few people do this. But it's surprisingly easy to get on the machine and change the password. This doesn't work in all cases (like if you made a GRUB password and forgot that too), but here's how you do it in a normal case with a Cent OS Linux example.

First reboot the system. When it reboots you'll come to the GRUB screen as shown in Figure 1. Move the arrow key so that you stay on this screen instead of proceeding all the way to a normal boot.

Figure 1. GRUB screen after reboot

Next, select the kernel that will boot with the arrow keys, and type E to edit the kernel line. You'll then see something like Figure 2:

Figure 2. Ready to edit the kernel line

Use the arrow key again to highlight the line that begins with kernel, and press E to edit the kernel parameters. When you get to the screen shown in Figure 3, simply append the number 1 to the arguments as shown in Figure 3:

Figure 3. Append the argument with the number 1

Then press Enter, B, and the kernel will boot up to single-user mode. Once here you can run the passwd command, changing password for user root:

sh-3.00# passwd New UNIX password: Retype new UNIX password: passwd: all authentication tokens updated successfully

Now you can reboot, and the machine will boot up with your new password.

Trick 5: SSH back door

Many times I'll be at a site where I need remote support from someone who is blocked on the outside by a company firewall. Few people realize that if you can get out to the world through a firewall, then it is relatively easy to open a hole so that the world can come into you.

In its crudest form, this is called "poking a hole in the firewall." I'll call it an SSH back door. To use it, you'll need a machine on the Internet that you can use as an intermediary.

In our example, we'll call our machine blackbox.example.com. The machine behind the company firewall is called ginger. Finally, the machine that technical support is on will be called tech. Figure 4 explains how this is set up.

Figure 4. Poking a hole in the firewall

Here's how to proceed:

Check that what you're doing is allowed, but make sure you ask the right people. Most people will cringe that you're opening the firewall, but what they don't understand is that it is completely encrypted. Furthermore, someone would need to hack your outside machine before getting into your company. Instead, you may belong to the school of "ask-for-forgiveness-instead-of-permission." Either way, use your judgment and don't blame me if this doesn't go your way.
SSH from ginger to blackbox.example.com with the -R flag. I'll assume that you're the root user on ginger and that tech will need the root user ID to help you with the system. With the -R flag, you'll forward instructions of port 2222 on blackbox to port 22 on ginger. This is how you set up an SSH tunnel. Note that only SSH traffic can come into ginger: You're not putting ginger out on the Internet naked.
You can do this with the following syntax:

~# ssh -R 2222:localhost:22 thedude@blackbox.example.com

Once you are into blackbox, you just need to stay logged in. I usually enter a command like:

thedude@blackbox:~$ while [ 1 ]; do date; sleep 300; done

to keep the machine busy. And minimize the window.
Now instruct your friends at tech to SSH as thedude into blackbox without using any special SSH flags. You'll have to give them your password:
root@tech:~# ssh thedude@blackbox.example.com .
Once tech is on the blackbox, they can SSH to ginger using the following command:
thedude@blackbox:~$: ssh -p 2222 root@localhost
Tech will then be prompted for a password. They should enter the root password of ginger.
Now you and support from tech can work together and solve the problem. You may even want to use screen together!

Trick 6: Remote VNC session through an SSH tunnel

VNC or virtual network computing has been around a long time. I typically find myself needing to use it when the remote server has some type of graphical program that is only available on that server.

For example, suppose in Trick 5, ginger is a storage server. Many storage devices come with a GUI program to manage the storage controllers. Often these GUI management tools need a direct connection to the storage through a network that is at times kept in a private subnet. Therefore, the only way to access this GUI is to do it from ginger.

You can try SSH'ing to ginger with the -X option and launch it that way, but many times the bandwidth required is too much and you'll get frustrated waiting. VNC is a much more network-friendly tool and is readily available for nearly all operating systems.

Let's assume that the setup is the same as in Trick 5, but you want tech to be able to get VNC access instead of SSH. In this case, you'll do something similar but forward VNC ports instead. Here's what you do:

Start a VNC server session on ginger. This is done by running something like:
root@ginger:~# vncserver -geometry 1024x768 -depth 24 :99

The options tell the VNC server to start up with a resolution of 1024x768 and a pixel depth of 24 bits per pixel. If you are using a really slow connection setting, 8 may be a better option. Using :99 specifies the port the VNC server will be accessible from. The VNC protocol starts at 5900 so specifying :99 means the server is accessible from port 5999.

When you start the session, you'll be asked to specify a password. The user ID will be the same user that you launched the VNC server from. (In our case, this is root.)
SSH from ginger to blackbox.example.com forwarding the port 5999 on blackbox to ginger. This is done from ginger by running the command:
root@ginger:~# ssh -R 5999:localhost:5999 thedude@blackbox.example.com

Once you run this command, you'll need to keep this SSH session open in order to keep the port forwarded to ginger. At this point if you were on blackbox, you could now access the VNC session on ginger by just running:

thedude@blackbox:~$ vncviewer localhost:99

That would forward the port through SSH to ginger. But we're interested in letting tech get VNC access to ginger. To accomplish this, you'll need another tunnel.
From tech, you open a tunnel via SSH to forward your port 5999 to port 5999 on blackbox. This would be done by running:
root@tech:~# ssh -L 5999:localhost:5999 thedude@blackbox.example.com

This time the SSH flag we used was -L, which instead of pushing 5999 to blackbox, pulled from it. Once you are in on blackbox, you'll need to leave this session open. Now you're ready to VNC from tech!
From tech, VNC to ginger by running the command:
root@tech:~# vncviewer localhost:99 .

Tech will now have a VNC session directly to ginger.

While the effort might seem like a bit much to set up, it beats flying across the country to fix the storage arrays. Also, if you practice this a few times, it becomes quite easy.

Let me add a trick to this trick: If tech was running the Windows® operating system and didn't have a command-line SSH client, then tech can run Putty. Putty can be set to forward SSH ports by looking in the options in the sidebar. If the port were 5902 instead of our example of 5999, then you would enter something like in Figure 5.

Figure 5. Putty can forward SSH ports for tunneling

If this were set up, then tech could VNC to localhost:2 just as if tech were running the Linux operating system.

Trick 7: Checking your bandwidth

Imagine this: Company A has a storage server named ginger and it is being NFS-mounted by a client node named beckham. Company A has decided they really want to get more bandwidth out of ginger because they have lots of nodes they want to have NFS mount ginger's shared filesystem.

The most common and cheapest way to do this is to bond two Gigabit ethernet NICs together. This is cheapest because usually you have an extra on-board NIC and an extra port on your switch somewhere.

So they do this. But now the question is: How much bandwidth do they really have?

Gigabit Ethernet has a theoretical limit of 128MBps. Where does that number come from? Well,

1Gb = 1024Mb; 1024Mb/8 = 128MB; "b" = "bits," "B" = "bytes"

But what is it that we actually see, and what is a good way to measure it? One tool I suggest is iperf. You can grab iperf like this:

# wget http://dast.nlanr.net/Projects/Iperf2.0/iperf-2.0.2.tar.gz

You'll need to install it on a shared filesystem that both ginger and beckham can see. or compile and install on both nodes. I'll compile it in the home directory of the bob user that is viewable on both nodes:

tar zxvf iperf*gz cd iperf-2.0.2 ./configure -prefix=/home/bob/perf make make install

On ginger, run:

# /home/bob/perf/bin/iperf -s -f M

This machine will act as the server and print out performance speeds in MBps.

On the beckham node, run:

# /home/bob/perf/bin/iperf -c ginger -P 4 -f M -w 256k -t 60

You'll see output in both screens telling you what the speed is. On a normal server with a Gigabit Ethernet adapter, you will probably see about 112MBps. This is normal as bandwidth is lost in the TCP stack and physical cables. By connecting two servers back-to-back, each with two bonded Ethernet cards, I got about 220MBps.

In reality, what you see with NFS on bonded networks is around 150-160MBps. Still, this gives you a good indication that your bandwidth is going to be about what you'd expect. If you see something much less, then you should check for a problem.

I recently ran into a case in which the bonding driver was used to bond two NICs that used different drivers. The performance was extremely poor, leading to about 20MBps in bandwidth, less than they would have gotten had they not bonded the Ethernet cards together!

Trick 8: Command-line scripting and utilities

A Linux systems administrator becomes more efficient by using command-line scripting with authority. This includes crafting loops and knowing how to parse data using utilities like awk, grep, and sed. There are many cases where doing so takes fewer keystrokes and lessens the likelihood of user errors.

For example, suppose you need to generate a new /etc/hosts file for a Linux cluster that you are about to install. The long way would be to add IP addresses in vi or your favorite text editor. However, it can be done by taking the already existing /etc/hosts file and appending the following to it by running this on the command line:

# P=1; for i in $(seq -w 200); do echo "192.168.99.$P n$i"; P=$(expr $P + 1); done >>/etc/hosts

Two hundred host names, n001 through n200, will then be created with IP addresses 192.168.99.1 through 192.168.99.200. Populating a file like this by hand runs the risk of inadvertently creating duplicate IP addresses or host names, so this is a good example of using the built-in command line to eliminate user errors. Please note that this is done in the bash shell, the default in most Linux distributions.

As another example, let's suppose you want to check that the memory size is the same in each of the compute nodes in the Linux cluster. In most cases of this sort, having a distributed or parallel shell would be the best practice, but for the sake of illustration, here's a way to do this using SSH.

Assume the SSH is set up to authenticate without a password. Then run:

# for num in $(seq -w 200); do ssh n$num free -tm | grep Mem | awk '{print $2}'; done | sort | uniq

A command line like this looks pretty terse. (It can be worse if you put regular expressions in it.) Let's pick it apart and uncover the mystery.

First you're doing a loop through 001-200. This padding with 0s in the front is done with the -w option to the seq command. Then you substitute the num variable to create the host you're going to SSH to. Once you have the target host, give the command to it. In this case, it's:

free -m | grep Mem | awk '{print $2}'

That command says to:

Use the free command to get the memory size in megabytes.
Take the output of that command and use grep to get the line that has the string Mem in it.
Take that line and use awk to print the second field, which is the total memory in the node.

This operation is performed on every node.

Once you have performed the command on every node, the entire output of all 200 nodes is piped (|d) to the sort command so that all the memory values are sorted.

Finally, you eliminate duplicates with the uniq command. This command will result in one of the following cases:

If all the nodes, n001-n200, have the same memory size, then only one number will be displayed. This is the size of memory as seen by each operating system.
If node memory size is different, you will see several memory size values.
Finally, if the SSH failed on a certain node, then you may see some error messages.

This command isn't perfect. If you find that a value of memory is different than what you expect, you won't know on which node it was or how many nodes there were. Another command may need to be issued for that.

What this trick does give you, though, is a fast way to check for something and quickly learn if something is wrong. This is it's real value: Speed to do a quick-and-dirty check.

Trick 9: Spying on the console

Some software prints error messages to the console that may not necessarily show up on your SSH session. Using the vcs devices can let you examine these. From within an SSH session, run the following command on a remote server: # cat /dev/vcs1. This will show you what is on the first console. You can also look at the other virtual terminals using 2, 3, etc. If a user is typing on the remote system, you'll be able to see what he typed.

In most data farms, using a remote terminal server, KVM, or even Serial Over LAN is the best way to view this information; it also provides the additional benefit of out-of-band viewing capabilities. Using the vcs device provides a fast in-band method that may be able to save you some time from going to the machine room and looking at the console.

Trick 10: Random system information collection

In Trick 8, you saw an example of using the command line to get information about the total memory in the system. In this trick, I'll offer up a few other methods to collect important information from the system you may need to verify, troubleshoot, or give to remote support.

First, let's gather information about the processor. This is easily done as follows:

# cat /proc/cpuinfo .

This command gives you information on the processor speed, quantity, and model. Using grep in many cases can give you the desired value.

A check that I do quite often is to ascertain the quantity of processors on the system. So, if I have purchased a dual processor quad-core server, I can run:

# cat /proc/cpuinfo | grep processor | wc -l .

I would then expect to see 8 as the value. If I don't, I call up the vendor and tell them to send me another processor.

Another piece of information I may require is disk information. This can be gotten with the df command. I usually add the -h flag so that I can see the output in gigabytes or megabytes. # df -h also shows how the disk was partitioned.

And to end the list, here's a way to look at the firmware of your system—a method to get the BIOS level and the firmware on the NIC.

To check the BIOS version, you can run the dmidecode command. Unfortunately, you can't easily grep for the information, so piping it is a less efficient way to do this. On my Lenovo T61 laptop, the output looks like this:

#dmidecode | less ... BIOS Information Vendor: LENOVO Version: 7LET52WW (1.22 ) Release Date: 08/27/2007 ...

This is much more efficient than rebooting your machine and looking at the POST output.

To examine the driver and firmware versions of your Ethernet adapter, run ethtool:

# ethtool -i eth0 driver: e1000 version: 7.3.20-k2-NAPI firmware-version: 0.3-0

Conclusion

There are thousands of tricks you can learn from someone's who's an expert at the command line. The best ways to learn are to:

Work with others. Share screen sessions and watch how others work—you'll see new approaches to doing things. You may need to swallow your pride and let other people drive, but often you can learn a lot.
Read the man pages. Seriously; reading man pages, even on commands you know like the back of your hand, can provide amazing insights. For example, did you know you can do network programming with awk?
Solve problems. As the system administrator, you are always solving problems whether they are created by you or by others. This is called experience, and experience makes you better and more efficient.

I hope at least one of these tricks helped you learn something you didn't know. Essential tricks like these make you more efficient and add to your experience, but most importantly, tricks give you more free time to do more interesting things, like playing video games. And the best administrators are lazy because they don't like to work. They find the fastest way to do a task and finish it quickly so they can continue in their lazy pursuits.

Linux on a roll in mobile phones

2009-04-30T01:11:00.000-07:00

It's only been about two years since Linux started becoming a significant factorin mobile phones, an arena that has been dominated by Symbian, Microsoft, and proprietary operating systems. With the burgeoning complexity of mobile phones, feature phones, and smart phones -- plus increasing time-to-market pressures -- there's a clear movement toward off-the-shelf, third-party operating systems based on industry standards, and Linux figures to be a major beneficiary of that trend.

How rosy is the mobile communications picture for Linux? Early indications in just the first two months of this year are that it will be very positive indeed. Consider Motorola, for example, one of the big three in mobile handsets, which brought its first Linux phone (pictured) to market in 2003. That company is expecting to introduce between eight and ten new Linux phones in 2005, according to the Taiwanese daily newspaper DigiTimes, representing more than 25 percent of the company's planned introductions for the year.

Today, smartphones running Linux represent over ten percent of Motorola's mobile phone sales in China, where it enjoys the number one market position. And China, of course, is the biggest market for mobile phones today. Motorola sources its Linux from MontaVista, as do two other major mobile phone vendors: NEC and Panasonic.

Yet Linux has had virtually no impact on the mobile phones being sold in the US. Nevertheless, with the (pictured), a heavily multimedia-oriented device, Motorola recently bowed its first Linux phone for the US market, which may presage more to come.

Trolltech certainly thinks so. That company is the provider of the Qtopia development environment and graphical user interface (pictured) used by many Linux mobile phone makers. Earlier this month, Trolltech CEO Haavard Nord told LinuxDevices.com that 2005 would be a "breakout" year for Linux mobile phones and predicted that over twenty new devices were on the way, representing a new market "surge" for Linux handsets. Notable among these will be the first Linux phone from Ningbo Bird, the largest Chinese mobile phone manufacturer and exporter, expected to be launched by the middle of this year.

Early 2005 also saw the completion of PalmSource's acquisition of China MobileSoft and the adoption of several of its software products, including a Linux software stack for smartphones. Previously, in December of 2004, PalmSource had announced its plans to migrate to Linux in pursuit of the feature phone and smart phone markets, as well as its intention to soon offer the PalmOS as a middleware and application stack for Linux mobile phones.

Elsewhere during early 2005, Texas Instruments bowed a mobile phone reference design that includes an embedded Linux software stack, and Sky MobileMedia Inc. announced the integration of its SKY-MAP software platform with MontaVista's embedded Linux operating system. According to Sky CEO Richard Sfeir, Linux is becoming "the operating platform of choice for handset manufacturers requiring a robust and high performing operating system." Many feature-phone makers are "migrating to Linux for higher performance products," he said.

Moreover, there was one other bit of news in early 2005 that bodes well for the future of Linux in mobile phones: the revelation at the 3GSM conference in February that a second of the big three mobile phone makers, Samsung Electronics, has collaborated on a reference design for a 3G Linux smartphone (pictured) with Infineon Technologies, Trolltech, and Emuzed. That design includes not just a Samsung application processor and camera module, but a Samsung optimized Linux kernel as well.

As for Nokia, it is the only one of the leading trio of mobile phone makers that has made no noise about Linux. That's not very surprising, however, since Nokia holds a major stake in Symbian, a vendor that Linux interests are trying to displace.

The balance of this article provides links to LinuxDevices.com coverage relating to the use of Linux in mobile phones. Enjoy . . . !

Setting up Squid as your caching HTTP/FTP proxy

2009-04-30T01:01:00.001-07:00

Squid is a proxy caching server for HTTP/FTP requests. It caches data off
the net on your local network. So the next time the same data is being
accessed, whether it is html or a gif, it gets served up from the local
server rather than over the Internet -- saving you significant bandwidth.

Lets use the most commonly available proxy server for Linux and the most
stable one around, Squid. Installing and configuring it is a breeze as
you'll soon find out. To make things simpler I would suggest that you get
the Squid RPM from any of the download on the net for your distro.The
latest Stable release of Squid is squid-2.3.STABLE1-5.i386.rpm. If you are
not able to find it on your distro's CD then i would suggest you try out
www.rpmfind.net. After having downloaded the RPM install it with the
following command.

Assuming you have downloaded the squid-2.3.STABLE1-5.i386.rpm release
the installation command is as follows.

bash# rpm -ivh squid-2.3.STABLE1-5.i386.rpm

And please do note that "bash#" stands for the shell prompt and you do not

need to replicate it in your command.

Having installed Squid sucessfully, now open the file /etc/squid.conf
using your favourite text editor. Some distributions put this file in
/etc/squid/. This is where it gets interesting and confusing too so read
carefully.

Scroll down till you come to the line

#http_port 3128

This option sets your HTTP proxy port to 3128 which is the default port
that squid runs on. You can uncomment this line and set it to whatever
port you want. It is advisable to avoid port 80 since, if you are running
a Web Server on the Linux machine Apache would be listening on that port.

Scroll down till you come to the line

#cache_mem 8 MB

This option sets a limit on the amount of memory that squid may make use
of to store it's transient and cached objects temporarily in memory. This
limit that you may impose on squid is the soft limit and at any given
point of time Squid may double or triple the size of occupied memory all
depending on the size and the requirement of in-transient cached objects.
Uncomment this line and change the size of your Memory cache from 8 MB to
what ever size you want it too be. Keep in mind the amount of RAM that you
have on your machine when you allocate memory to SQUID. But for your
knowledge this occupancy of the specified Memory Limit is dynamic.

Scroll down until you come to the following lines

# LOGFILE PATHNAMES & CACHE DIRECTORIES
#--------------------------------------------------------------------------

The following options are relative to setting up and tuning your web
cache. So lets get gunning pals. Here the first and most important one.

#cache_dir /var/squid/cache 100 16 256

Isn't this getting a little confusing, one parameter and three values to
it! C'mon let's demystify the whole thing. The values given here are the
values the Squid will use by default. So if the 'cache_dir' option isn't
implicitly mentioned then Squid resolves to maintaining the cache in
/var/squid/cache. Uncomment this option 'cache_dir' if you want to
customize the parameters.

The first parameter '/var/squid/cache' is the path to the cache files. You
may change this to suit whatever you want too, but remember whatever path
you may mention out here make sure that those directories exist because
Squid will never create the directories on it's own. Also a point to be
noted is that the directories should be writable by the Squid process. If
you are a novice and all of this is sounding too geekish then I suggest
you stick to the default values.

The next value '100' is the amount of space in MegaBytes(MB) that Squid
can utilize to store the cache contents. Modify this to whatever you think
is appropriate to suit your needs.

The next value referred to as 'Level-1' is the number of sub-directories
that Squid can create under the current Cache directory. I suggest that
for starters leave this as it is.

The next option is referred to as 'Level-2' is the number of Second Level
directories that Squid can create under each 'Level-1' directory. The
default is fine for the moment.

Scroll down till you come to the line:

# ACCESS CONTROLS
# -----------------------------------------------------------------------------

The following lines define Access Control Lists for your Network. Squid
allows you to define various kinds of ACL's out here. So make it a point
to read this whole section of Access Controls carefully.

In this "ACCESS CONTROLS" section scroll down till you come to the
following lines.

#Default configuration:
http_access allow manager localhost
http_access deny manager
http_access deny !Safe_ports
http_access deny CONNECT !SSL_ports
#
# INSERT YOUR OWN RULE(S) HERE TO ALLOW ACCESS FROM YOUR
# CLIENTS
#
http_access deny all

What you need to do out here, is to setup your own ACL's (Access Control
Lists), else just comment out the last line as shown above and put the
following line in.

http_access allow all

So now your rule section should look like this.

# INSERT YOUR OWN RULE(S) HERE TO ALLOW ACCESS FROM YOUR
# CLIENTS

#http_access deny all
http_access allow all

Three cheers and your proxy has been setup. Now you only need to make sure
that Squid starts every time your Linux box boots.

If your using RedHat then you can start in the following manner. Login as
Admin or "su" to root & use the "setup" command. Now enter the System
Services sub menu and enable Squid.

If your using SuSE then start YaST and go to "System Administration", then
go to "Change config File", then scroll down till you come to "START
SQUID" & just enable it from "NO" to "YES".

The next time you reboot your machine your Proxy will start automatically.

Before you start using squid you need to create the swap directories. Do
this by

/usr/sbin/squid -z

This just has to be done the first time.

To start Squid right now use the following command

bash#/etc/rc.d/init.t/squid start

There, you have setup, configured and started your proxy. Just make sure
your client's web browsers have the http proxy port setup as the same port
in your /etc/squid.conf file.

Running Microsoft Windows inside Debian: qemu

2009-04-30T00:58:00.000-07:00

here are many legitimate reasons for a Debian GNU/Linux user to wish to run Microsoft Windows applications. One approach involves using the wine program to run a single Windows executable in a fake Windows environment. An alternative is to run an entire Windows operating system within a Debian host. Qemu is a procesor emulator and virtualization program which allows you to do just that.

Qemu is available for Debian's unstable distribution, and can be installed from the source code available on its homepage for Woody. It is comparible to the commercial software VMWare albeit with a few features missing and a lower performance.

On the plus side it is evolving fast, and doesnt require complicated setup or kernel patching. It is also free - although if you wish to run an installation of Windows you will need a valid license to do so.

Qemu is a complete CPU and peripheral emulator which can be used to run entire operating systems as a user process, supported operating systems include Linux distributions such as Debian, RedHat, SuSE, varieties of Microsoft Windows such as Windows 98, Windows 2000, and Windows XP and BSD based operating systems. There are some disk images available from the Free OS Zoo website.

Whilst it's not as fast as running an operating system directly on the same hardware because of the overhead of virtualising running as a guest operating system is suprisingly responsive on my AMD XP 2800+ machine, once the slow installation is achieved.

This brief guide will walk you through installing Windows 2000 as a guest operating system on your Debian box.

First of all you need to install qemu, by running as root:

apt-get install qemu

Once this is done we're ready to start the installation process.

As qemu is a virtualization program it doesnt touch your real discs, instead you give it a big file and tell the system to use that for it's C:.

As a simple start we'll set aside a blank 2Gb file for Windows to install into, we can create that easily enough:

skx@undecided:~$ dd of=hd.img bs=1024 seek=2000000 count=0
0+0 records in
0+0 records out
0 bytes transferred in 0.000493 seconds (0 bytes/sec)

That's given us a file called hd.img which is 2000000 bytes long, close enough to 2Gb for us to proceed.

The next thing we need to do is have a Windows 2000 CD-ROM handy, we have two choices here either place it in your CD-ROM drive, or use an ISO image.

We'll go with the former.

We want to tell the system that it's first hard drive should be the big empty file we have just created, that the CD-ROM drive should be read from the drive we have - and that it should boot from CD-ROM.

skx@undecided:~$ qemu -boot d -cdrom /dev/cdrom  -hda hd.img
QEMU 0.6.0 monitor - type 'help' for more information

The '-boot d' flag tells the system to boot from the CD-ROM drive we've specified, the '-hda hd.img' tells the system that the first hard drive should be the contents of the file hd.img which we created previously.

This should bring up a window upon your desktop within which you'll see Windows boot. You can click in the window to give it focus, and when you wish to return the mouse to your desktop press "Ctrl + Shift". Pressing Ctrl + Shift + f will toggle you between fullscreen and windowed mode.

Now you can sit back and install Windows as you normally would. Some parts will be very slow, other parts such as formatting the drive will be lightening fast!

Whilst using the guest operating system is acceptably responsive for me the actual installation took a couple of hours. Most of this is waiting for the thing to finish, but it's something to be aware of.

I found that when I installed Windows 2000 it seemed to go faster if I ran it fullscreen and shut down as many open programs as I could.

When it came to networking I found that Debian doesn't allow non-root users to write to the tun driver by default, as root run:

chgrp users /dev/net/tun
chmod g+w /dev/net/tun

(If you don't have that device file you will need to run these commands, this assumes you're running Kernel 2.6.x)

mkdir -p /dev/net
mknod /dev/net/tun c 10 200

Finally we add in the module to enable the device :

modprobe tun
echo 'tun' >> /etc/modules

Now that you're installed the operating system you can create a backup of the image by simply copying the 'hd.img' file which is being used as the disk drive:

skx@undecided:~$ cp hd.img pristine.img

Any time you wish to restore back simply overwrite the hd.img with the pristine one - you'll never have to reinstall again!

Now that we've done the installation we can start the system for real with:

skx@undecided:~$ qemu -hda hd.img -boot c

From bootup to login prompt takes me 39 seconds, which is pretty impressive.

Networking should be setup properly for you in the sense that on the host machine you will have the interface tun0 setup.

Once that's done you need to setup some way for the emulated machine to talk to the world, or it's host at least.

I chose to give the host machine an IP address on it's own network. We do this by first setting up an address on the host, then on the guest.

I use 10.0.0.1 for the host, and 10.0.0.2 for the Windows system.

On the host run:

root@undecided:~# ifconfig tun0 10.0.0.1 up

Then on the host adjust the networking so that the Windows operating system has the ip address 10.0.0.2, with the gateway set to point to 10.0.0.1.

This should allow you to ping both the guest from the host, and vice versa.

If you wish the host to be able to talk to the internet generally run the following on the host:

root@undecided:~# iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE
root@undecided:~# echo "1" >/proc/sys/net/ipv4/ip_forward

A comprehensive command guide to Debian’s APT-GET and DPKG

2009-04-29T00:06:00.000-07:00

Purpose: Debian has a very powerful package management system called APT. Learning some useful commands can really unleash the true power and usefulness of this package management system. From time to time I will add commands and other tips and tricks that will be helpful to solve some issues and get work done faster. The idea is to make this post a COMPREHENSIVE command guide for APT package management.

Note: For most of the examples, I have used “traceroute” as an example package wherever possible. In some scenarios I have used other packages for the example since traceroute was not suitable for those.

APT-GET Commands

To install a package. For example, let say you would like to install traceroute package:

#apt-get install traceroute

To install a package’s source files. For example, let say you would like to download “traceroute” package’s source:

# apt-get source traceroute

To install dependencies of a package for building the package from it’s source. For example, before you start building a binary package (traceroute) from it’s source, you need to install the dependencies that are required to build the package from it’s source:

# apt-get build-dep traceroute

To build a package from it’s source:

# apt-get source traceroute # cd traceroute-VERSION # debuild -uc -us # cd ..

To fix a system with incorrect/broken dependencies. Also useful if the apt-get was stopped unexpectedly due to crash or power failure:

# apt-get -f install

DPKG Commands

To reconfigure any package that is unpacked but not yet configured or half-configured state. This can be used along with “apt-get -f install”. Also useful in case of unexpected shutdown while upgrading the system.

# apt-get -f install
# dpkg --configure -a

To remove a package (this does not remove the configuration files the package):

# dpkg --remove traceroute

To remove a package (and its configuration files):

# dpkg --purge traceroute

To reconfigure a package. For example suppose you want to select a different settings for your X server:

# dpkg-reconfigure xserver-xorg

To identify the package name that produced a particular file. For example, “I would like to know which Debian package produced the file ‘lft.db’:

# dpkg -S lft.db
or
# dpkg --search lft.db

Output:

traceroute: /usr/bin/lft.db
traceroute: /usr/share/man/man8/lft.db.8.gz

To list all the files installed a particular package:

# dpkg --listfiles traceroute

To list all the packages installed on the system along with their state, name, version and a description:

# dpkg --list

To list all the packages installed on the system (only names):

# dpkg --get-selections

To troubleshoot error messages like the following:

Unpacking dictionaries-common (from …/dictionaries-common_0.98.12_all.deb) …
dpkg-divert: cannot open diversions: No such file or directory
dpkg: error processing /var/cache/apt/archives/dictionaries-common_0.98.12_all.deb (–unpack):
subprocess pre-installation script returned error exit status 2
Selecting previously deselected package aspell.
Unpacking aspell (from …/aspell_0.60.6-1_i386.deb) …
Processing triggers for man-db …
Errors were encountered while processing:
/var/cache/apt/archives/dictionaries-common_0.98.12_all.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)
debian-486:/var/lib/dpkg# ls

# touch /var/lib/dpkg/diversions

To troubleshoot error messages like following:

Errors were encountered while processing:
/var/cache/apt/archives/acpid_ 1.0.8-7.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)

Try following commands one by one:

# apt-get -f install # apt-get upgrade # apt-get dist-upgrade

# dpkg --configure -a # apt-get -f install

# cd /var/lib/dpkg/info # rm -rf acpid* # apt-get install acpid

# cd /var/lib/apt/lists # rm * # apt-get update # apt-get install acpid

# cd /var/cache/apt/archives # rm acpid_ 1.0.8-7.deb # apt-get install acpid

APT-CACHE Commands

To perform a full-text search on a package’s name, description, etc:

# apt-cache search traceroute

To print detailed information of a package:

# apt-cache show traceroute

To print a list of packages a given package (traceroute) depends on. For example, show me all the packages on which traceroute depends:

# apt-cache depends traceroute

Output:

traceroute
Depends: libc6
Conflicts: tcptraceroute
Conflicts:
Conflicts: traceroute-nanog

To print a list of packages that are dependent on a particular package. For example, show me all the packages that are dependent on “traceroute” package:

# apt-cache rdepends traceroute

Output:

Reverse Depends:
xorp
traceroute-nanog
traceroute-nanog
licq
traceroute-nanog
ksniffer
traceroute-nanog
iputils-tracepath
traceroute-nanog
gnome-nettool
traceroute-nanog
education-common
traceroute-nanog

To print detailed information of the versions available for a package and the packages that reverse-depends on it. For example, show me all the packages which depends on traceroute:

# apt-cache showpkg traceroute

Happy Debians! :)

CLI Magic: For geek cred, try these one-liners

2009-04-29T00:02:00.000-07:00

In this context, a one-liner is a set of commands normally joined through a pipe (|). When joined by a pipe, the command on the left passes its output to the command on the right. Simple or complex, you can get useful results from a single line at the bash command prompt.

For example, suppose you want to know how many files are in the current directory. You can run:

rakesh@debian ~]$ ls | wc -l

That's a very simple example -- you can get more elaborate. Suppose you want to know about the five processes that are consuming the most CPU time on your system:

rakesh@debian ~]$ ps -eo user,pcpu,pid,cmd | sort -r -k2 | head -6

The ps command's o lets you specify the columns that you want to be shown. sort -r does a reverse order sort with the second column (pcpu) as reference (k2). head gets only the first six lines from the ordered list, which includes the header line. You can place pcpu as the first column and then omit the k2 option because sort by default takes the first column to do the sort. That illustrates how you may have to try several approaches on some one-liners; different versions and ways to manipulate the options may produce different results.

A common situation for Linux administrators on servers with several users is to get quick ordered user lists. One simple way to get that is with the command:

rakesh@debian ~]$ cat /etc/passwd | sort

If you just need the username, the above command returns too much information. You can fix it with something like this:

rakesh@debian ~]$ cat /etc/passwd | sort | cut -d":" -f1

The sorted list is passed to cut, where the d option indicates the field's delimiter character. cut breaks into pieces each line, and the first field f1 is the one that you need to display. That's better; it shows only usernames now. But you may not want to see all the system usernames, like apache, bin, and lp. If you just want human users, try this:

rakesh@debian ~]$ cat /etc/passwd | sort | gawk '$3 >= 500 {print $1 }' FS=":"

gawk evaluates each line from the output piped to it. If the third field -- the UID -- is equal or greater than 500 (most modern distros start numbering normal users from this number) then the action is done. The action, indicated between braces, is to print the first field, which is the username. The separator for field in the gawk command is a colon, as specified by the FS option.

Now suppose you have a directory with lots of files with different extensions, and you want to back up only the .php files, calling them filename.bkp. The next one-liner should do the job:

rakesh@debian ~]$ for f in *.php; do cp $f $f.bkp; done

This command loops through all the files in the current directory looking for those with .php extensions. Each file's name is held in the $f variable. A simple copy command then does the backup. Notice that in this example we used a semicolon to execute the commands one after another, rather than piping output between them.

What about bulk copy? Consider this:

rakesh@debian ~]$ tar cf - . | (cd /usr/backups/; tar xfp -)

It creates a tar package recursevely on the current directory, then pipes this package to the next command. The parenthesis creates a temporary subshell, changes to a different directory, then extracts the content of the package, which is the whole original directory. The p option on the last tar command preserves file properties like time and permissions. After completion, the shell context will be at the original directory.

A variant on the previous one-liner lets you do the same kind of backup on a remote server:

rakesh@debian ~]$ tar cf - . | ssh smith@remote.server tar xfp - -C /usr/backup/smith

Here, the command establishes an SSH remote session and untars the package with the C option, which changes the directory, in this case to /usr/backup/smith, where the extraction will be made.

grep and gawk and uniq, oh my!

Text processing is a common use for one-liners. You can accomplish marvelous things with the right set of commands. In the next example, suppose you want a report on incoming email messages that look like this:


rakesh@debian ~]$ cat incoming_emails
2008-07-01 08:23:17 user1@example.com
2008-07-01 08:25:20 user2@someplace.com
2008-07-01 08:32:41 somebody@server.net
2008-07-01 08:35:03 spam not recived, filtered
2008-07-01 08:39:57 user1@example.com
...

You are asked for a report with an ordered list of who received incoming messages. Many recipients would be repeated in the output of the cat command. This one-liner resolves the problem:

rakesh@debian ~]$ grep '@' incoming_email | gawk '{print $3}' | sort | uniq

grep filters the lines that contains a @ character, which indicates an email address. Next, gawk extracts the third field, which contains the email address, and passes it to the sort command. Sorting is needed to group the same recipients together because the last command, uniq, omits repeated lines from the sorted list. The output is shown below. Most text processing one-liners use a combination of grep, sed, awk, order, tr, cut, uniq, and other related commands.


somebody@server.net
user1@example.com
user2@someplace.com

If you like any of these one-liners but think they're too long to type often, you can create an alias for the command and put it in your .bashrc file. When you log in your session, anything inside this file will be run, so your personal aliases would be ready at anytime.

rakesh@debian ~]$ alias p5="ps -eo pcpu,user,pid,cmd | sort -r | head -6"

You can certainly create better and simpler variations of all of the commands in this article, but they're a good place to start. If you are a Linux system administrator, it's good practice to collect, create, and modify your own one-liners and keep them handy; you never know when are you going to need them. If you have a good one-liner, feel free to share it with other readers in a comment below.

Seamlessly integrate XP into Linux with SeamlessRDP

2009-04-28T23:51:00.000-07:00

Today users have many choices for combining Linux and Windows on the same machine. You can go with a traditional dual-boot system in which the operating systems reside on different disk partitions but share a common partition for files, or you can use an emulator such as Wine, which lets you install Windows applications right in your Linux system. Virtualization programs, such as those from VMware, bring you closer to the more ideal solution of using both systems at once, but one is always the host and one is always the guest, shown inside a window. But by combining VMware Server with some free software, you can run Windows XP along with Linux, not inside a console window, but completely integrated into the Linux environment.

To make this work, you need three tools installed on your system. Though not open source, VMware Server is free as in beer; it requires a license number that you get from the same page where you download the program. (Of course you also need a copy of Windows XP to run under VMware Server.) rdesktop is a Remote Desktop Protocol client bundled with virtually every Linux distro, and Cendio's SeamlessRDP is a GPL-licensed utility that lets you integrate rdesktop with Windows XP.

With this solution, you're connecting to a virtual machine in the background, but you don't see a window frame or the Windows desktop. All you see is the Windows XP menu bar along with your regular KDE or GNOME menu bar, creating the illusion that both operating systems are working at the same time side by side. In Figure 1. below, notice the KDE menu bar on the top and the Windows XP menu bar on the bottom of the screen. You can launch applications from both.

To start, install Windows XP in VMware with the usual options, and make sure to set the network connection option to Network Address Translation (NAT). This simplifies the connection from the host machine. After you complete the Windows installation, log in and set a password for an account you've created that you'll call from Linux. You must allow remote connections to this Windows virtual machine, which you can do by going to Start -> Control Panel -> System (you may have to switch to the classic view). Once the system icon opens, go to the Remote tab and check "Allow users to connect remotely to this computer."

Now install VMware Tools for your Windows XP virtual machine. You must know which IP address the VMware DHCP server assigned to the virtual machine; to find it, open up a DOS console and type ipconfig.

Click to enlarge Next, install SeamlessRDP from within your Windows virtual machine. Open Internet Explorer and download the SeamlessRDP zip file. Create a directory under C: (C:\seamless) and extract the archive's content there. Unzip the three files into the directory; you'll use seamlessrdpshell.exe later.

Now you can log off the Windows session, but don't turn off the virtual machine. Once you have Windows displaying the Welcome screen, you can close the VMware Server console, leaving the Windows XP virtual machine session is alive in the background. A simple ps -ef | grep vmware proves it's still there.

Now it's time to use rdesktop. First, try to open a simple application, such as Notepad. Start a terminal session under Linux, and run this command from your xterm:

rdesktop -A -s "c:\seamless\seamlessrdpshell.exe notepad" 192.168.217.129 -u admin -p secret

Of course, change the IP address, username, and password to match your settings. If everything is OK, you should see the Notepad application pop up on your Linux system.

The -A option enables the SeamlessRDP mode that creates an X11 window for each application you launch. This option requires you to set a shell (-s) that launches the application indicated in the rdesktop command. Notice that you're using the directory you created and the SeamlessRDP application, c:\seamless\seamlessrdpshell.exe. The argument to this command is the Windows program that you wish to run. You need the full path if the program isn't in the regular path variable.

The -u and -p switches are optional. If you don't use them, the application will launch a Windows login screen asking for credentials.

Note that when you close Notepad or any other Windows-launched application, the rdesktop connection is still on. You must log out, because until you do, rdesktop won't be able to start other applications. Since you don't have a desktop and a Start menu from which to log off, you must go to the Windows XP virtual machine and press Ctrl-Alt-Del, then log off, or restart the virtual machine.

Once you know how to launch a Windows application from rdesktop with the SeamlessRDP option, try it with explorer.exe itself. This application creates a full desktop environment so users can interact mainly through the menu bar. If you run it "as is," it will pop up the full Windows XP desktop (including the wallpaper, icons, and shortcuts on the desktop).

If that's too intrusive for you, you can hack the Windows registry to get rid of the desktop and keep only the menu bar. Once you're in Windows XP again, launch the Registry editor by going to Start -> Run and typing regedit. Search for HKEY_CURRENT_USER -> Software -> Microsoft -> Windows -> CurrentVersion -> Policies -> Explorer. Once there, right-click on the right panel and select New -> DWORD Value. Name it NoDesktop, then click on it and change the data value to 1. Close the Registry editor and restart Windows.

When you turn off your Linux system, any virtual machine that is running in the background will obviously be lost, so you must start the VMware virtual machine and close the server console every time you want to connect to Windows this way. Before running the rdesktop command, consider moving your menu bar from the bottom of the screen to the top, because the Windows bar will sit there.

Now run the rdesktop command like this:

rdesktop -A -s 'c:\seamless\seamlessrdpshell.exe c:\windows\explorer.exe' 192.168.217.129 -u admin -p secret

Voilà! After a few seconds, you should have the Windows XP menu bar at the bottom of the screen, and you should be able to launch any application you have installed. You've created the illusion that both operating systems are working on the same machine at the same time. Very cool.

This trick doesn't work with just VMware virtual machines. It also works with Windows clients on your network and other virtual machine software. Simply install SeamlessRDP and configure Windows XP properly so that rdesktop can connect to it.

TIP: Pretending IceWeasel to be Firefox in Debian Linux

2009-04-28T23:45:00.000-07:00

For those of you who have been using Debian Linux, you probably already know that the famous “Firefox” browser is called “IceWeasel” in Debian because of some licensing issues. There is nothing wrong with “IceWeasel” as only the name is changed. However there are some websites which will offer you different functionality based on the type of browser that you are using.

For example, if you would like to download Alexa Toolbar for IceWeasel in Debian Linux, you probably won’t able to because the Alexa website does not recognize “IceWeasel” although it is “FireFox” in reality with just a different brand name. It will tell you that your browser is not supported or recognized or something like that. What do you do in cases like these? Should you just give up? No, you should not. I will show you a trick by which you can make your “IceWeasel” appear as “FireFox” to websites like Alexa.

Step 1: Open your IceWeasel Web-browser

Now type:

about:config

in your URL/Address bar like this:

and click on “I’ll be careful, I promise!” button.

Step 2: Search for Iceweasel in the filter bar

You will see a “Filter” bar just below the URL/Address bar. Now type “iceweasel” (with quotes) in it and you will see some results in the result box below it as show below:

What you see above is very similar to Windows Registry key concept.

Step 3: Modify the string value

Now select the entry with name similar to “general.useragent.extra.firefox” and right-click on it and select “Modify”. An input box will appear with value set to:
"Iceweasel/3.0.6"

will appear as shown above. Now change this to something like:
"Firefox/3.0.6"

Click “OK”.

Now close your browser and again open your web browser. Try going to the Alexa website and now it will welcome your browser (which it thinks as Firefox) and will allow you to download the toolbar.

Happy Firefoxing with Iceweasel!

Add Digg To Blogger.com Posts

2009-04-28T10:59:00.000-07:00

After a poking around the xml template for my site, and playing around with the Digg code, I've figured out how to add a Digg button to my posts.
Listed below is a quick how-to for adding this functionality to your website too.

Make sure your blog is set to enable Post Pages and you are using the new Blogger, not the classic version

Go to the customization section of your blog, on the Template tab select Edit HTML

Make sure to click Download Full Template and save a backup copy to disk - just in case.

Put a check in Expand Widget Templates.

Search for
Update: March 5th, 2009

It has come to my attention that some templates use a slightly different formatting. If you cannot find the text listed above - try searching for and follow the rest of the instructions.

Paste this on the line directly before it: