Upgrading Ubuntu at work can make you rather unpopular, as the Internet bandwidth is fully utilised downloading all the updates to packages you have long since forgotten that you installed.

It also takes time, time that you should be working rather than upgrading your computer.

For these reasons I like to trickle download the upgrade over a day and only perform the actual upgrade once all the packages are ready, typically the following morning.

This is how I performed my low-bandwidth upgrade…

N.B. This is not the official or recommended way of upgrading between Ubuntu versions. Specifically my method involves manually disabling some repositories and updating others to the new release. This would normally be done by the do-release-upgrade program itself. It works for me, but please do be aware that you are deviating slightly from the official method.

Step 1: Disable 3rd Party Repositories

Launch the Ubuntu Software Centre and from the menu select Edit followed by Software Sources. Under the Other Software tab please untick all active repositories.

(This step should in any case be done automatically by step 4).

Step 2: Update Repositories

Edit /etc/apt/sources.list and replace all occurrences of  ”precise” with “trusty”. If you are of a brave disposition, the following command should do this for you:

$ sudo sed -i.bak 's/precise/trusty/g' sources.list

(This will create a copy of sources.list to sources.list.bak, in case you wish to reverse this.)

Step 3: Download Packages

Still in the terminal, type:

$ sudo apt-get updatesudo apt-get -o Acquire::http::Dl-Limit=64 -d dist-upgrade

The 64 will limit the bandwidth to 64 Kbps, please adjust to suit your available bandwidth. The “-d” will instruct apt-get to merely download the packages and not to install them.

I believe this stage can be aborted with Ctrl+C at any time and run again, until such time as all the required packages are downloaded.

Step 4: Upgrade

Still in the terminal, I tend to use GNU Screen for extra resilience, type:

$ sudo do-release-upgrade

Conclusion

I am typing this on my newly upgraded 14.04 installation, after a clean and trouble-free reboot and an entirely fault-free upgrade.

The truly astonishing aspect to an upgrade is the fact that the computer remains largely usable throughout. I lost my fonts briefly in one application during Step 4, but otherwise I was able to work normally. It didn’t even seem to be slowing my computer down greatly, although this is a fairly powerful workhorse, so your mileage may vary.

Please do comment, if you feel I’ve left anything out in the above, or indeed if you have found it useful.

Good luck with your upgrade.

I finally decided to upgrade my work desktop to Debian Squeeze:

Preparing for the Upgrade

I manually removed all but the official lenny repositories (and removed the Debian Volatile repository which is no longer used), and updated them to “squeeze”:

$ sudo vim /etc/apt/sources.list
deb http://91.121.125.139/debian/ squeeze main non-free contrib
deb-src http://91.121.125.139/debian/ squeeze main non-free contrib

deb http://security.debian.org/ squeeze/updates main non-free contrib
deb-src http://security.debian.org/ squeeze/updates main non-free contrib

Next, in order to minimise download time, I reviewed my installed packages:

$ sudo dpkg -l | grep "ii " | less

And I removed all the unnecessary packages. In particular I decided to remove all of KDE, as I am now using pekwm. When removing packages I found apt-get kept trying to upgrade large numbers of packages. Aptitude was much better, as instead of just trying to install a load of packages, it reported the problem (e.g. package XYZ will be broken by this change) and let me choose the solution. I just added the packages that would be broken to the list of packages to be removed.

Upgrade apt and dpkg

Then I installed apt and dpkg, to save these from having to be upgraded during the upgrade process:

$ sudo apt-get update
$ sudo apt-get install apt dpkg

Upgrade to Squeeze

Lastly, I ran the upgrade to squeeze with:

$ sudo apt-get dist-upgrade

During the upgrade I receive warnings about /lib/firmware/e100 missing. Mindful of the Debian’s much touted removal of non-free drivers, I did an apt-file search e100 which revealed that I needed to install the firmware-linux-nonfree package. This done, I rebooted.

First Boot

It booted fine to the command prompt, but of course without a login manager it got no further. I simply typed startx to get into pekwm and it all worked perfectly.

Installing KDE

I decided to install KDE again, although I would struggle to explain why, curiosity perhaps. I installed kde-core and it all just worked perfectly, with a neat first time wizard to handle the migration of configuration from KDE3.5 to KDE4, excellent work.

I used KDE4 for a few hours before returning to pekwm.

Conclusions

So far Squeeze has been flawless and yet another Debian dist-upgrade without a hitch. Well done Debian.

KDE looks great and seemed to work exactly as it ought. Over the few hours I encountered no problems whatsoever. But I do wish KDE would learn from some of the features of PekWM - I just love the left-mouse-click on the screen edge to move to the next window, I love the ability to group windows and I love the fact that you can resize windows to fill the available space.

I am not saying that all those features should be made the default in KDE, such matters are subjective, but they ought to at least be possible in KDE and as far as I can tell they are not. There is a screen edge option, but it works poorly, relying on you holding the mouse at the screen edge for a definable period of time.

apt-get

For apt-get you just need to create a new file:

/etc/apt/apt.conf.d/76download

with the following contents:

$ sudo vim /etc/apt/apt.conf.d/76download 
Acquire {
    Queue-mode "access";
    http {
        Dl-Limit "128";
    };
};
$

The above will limit your bandwidth to 128K, adjust this figure to suit your network.

Alternatively, if you don’t want this change to be set permanently, then you can specify it in the command line:

$ sudo apt-get -o Acquire::http::Dl-Limit=128 upgrade

wget

To rate-limit wget, simply edit /etc/wgetrc or your personal configuration at ~/.wgetrc and add or edit the following line:

limit-rate=128k

other

Other packages can be configured in different ways, but you could install trickle and then read its man page to determine how to use it. For example (from the man page):

$ trickle -u 128 -d 128 ncftp

This doesn’t give you the entire picture, as it only lists the dependencies that you don’t already have; which is usually all you care about, but there are occasions when you would like to list all of a package’s dependencies, for example when planning for a system that is not built yet, or not accessible at the current time. Or just for idle curiosity! Perhaps that’s just me.

Anyhow, apt-rdepends is the application for the job. It doesn’t just list the package’s dependencies, but it recursively goes through each dependency’s dependencies.

Install it with the usual $ sudo apt-get install apt-rdepends and then simply run with:

$ apt-rdepends packagename | less

Yes, it is quite verbose, hence the “| less” - leave it out if you prefer, or use “| more” which is more likely to be installed on your system (tip: install “less” - less is better than more, if that makes any sense).

For example, I had just installed “flite” and was amazed at how functional it was. I wondered to myself whether it was just a front-end to festival - but how to find out?

$ apt-rdepends flite

Which comes back with no other speech synthesis engine (e.g. festival), so clearly flite is a speech synthesis engine in its own right.