Friday, 10 August 2007

Don't feel like downloading another CD?

Trying out Linux doesn't have to mean downloading a 700MB CD image and then having to burn it onto a CD. Thanks to the university software mirrors you have at least three places where you can go to get CD images for free.

Option 1: - The Department of Computer Science software mirror. Clicking on the 'iso' or 'linux' folders will give you access to a large variety of the most popular distributions, including some less known ones. The mirror is kept fairly up to date and if they don't have what you're looking for you can always email the CS mirror maintainers and ask them nicely to help you out. The mirror has a host of other software as well and it's all FREE!!

Option 2: - The Department of Electrical and Computer Engineering FTP server. Although compared to the Computer Science mirror the FTP server has a sparse collection of Linux distro's, they do host an Ubuntu and Debian software repositories, which have most of the software programs you are ever gonna need.

Option 3: - This is the server which all of the Linux machines in the labs get their updates from. Not much in the way of CD images here, just a Debian, Ubuntu and possibly RedHat repository.

Once you've chosen your distro, download it to /tmp, under Linux or C:\usertmp. under Windows and then burn it to disc (most of the CS lab computers have CD burners). If you try to save the CD image to your afs drive (H: drive) it will most likely tell you that it can't do it due to a lack of space. The default allocation for Science students is about 300MB. If you download to the temporary folders though, don't expect to be able to access your files the next time you log in. The files in those directories are deleted regularly.

Sunday, 5 August 2007

Keep your Ubuntu System up to date for free

Have you ever been at home just browsing the net, when all of a sudden that orange update icon pops us? You click on it only to discover a new version of Open Office and an associated 200MB download. You look at your internet usage only to find that you are only 250MB away from your monthly limit with two days to go. So reluctantly you click to download and install the package and then realize you have to go find something to do for half an hour while the package downloads.
This how-to tells you how to avoid having to waste time and bandwidth by using the university's repository. It should be particularly useful for people with slow connection speeds or low monthly data allocations.

To do this we need to first write down the names of the packages that need updating, their version numbers and which section of the repository they are from (main, universe, multiverse).

1. Start up Synaptic and click on the section 'Installed (upgradable)' in the left hand listbox. In the right hand section of the window you should see the packages that need upgrading.

e.g. tcpdump from version 3.9.5-2 to 3.9.5-2ubuntu1

2. Right click on a package and select 'Properties'. In the 'Common' tab, there is a line which says 'Section: .....'
Packages from the main repository will just have the section name. Packages from the universe repository will have '(universe)' at the end of the line. Packages from the multiverse repository will have '(multiverse)' at the end of the line.

e.g. for our example package tcpdump it says 'Section: Networking' meaning that it is in the main repository.

We now have the info we need. Now we can go to uni and navigate to This is the ftp server of the Department of Electrical and Computer Engineering and is only available at uni. The server has a lot of software available, so feel free to look around.

3. The part we are interested in is the ubuntu repository. So we are going to navigate to ubuntu --> pool --> [the repository of your package] --> [the first letter of your package] --> [the name of your package] -->

e.g. -> ubuntu --> pool --> main --> t --> tcpdump -->

4. Once there, simply find the files which match the version number of our upgrade and end in .deb

e.g. tcpdump_3.9.5-2ubuntu1_amd64.deb

5. Select the file which matches your processor architecture and save it to your USB drive.

6. Take it home and double click on the file. You will get a warning saying that the package is available through the internet and that you should install it from there. Ignore it and install the package.

If you have a laptop or you feel like taking your computer to uni one day the process is even easier. Simply open your sources.list file and add
deb feisty main restricted universe multiverse
and then run apt-get or synaptic.

This method is also good for upgrading or installing new software.