When upgrading a desupported version of Ubuntu, make sure to include the prescribed old-releases.ubuntu.com URLs in your sources.list, but also comment out the corresponding URLs from the regular releases site.

Shamefully, I let the OS on the VPS (virtual private server) which runs this blog fall out of support. I was running Ubuntu 9.10 (Karmic Koala – shudder), which apparently went of of support in – yikes! – April of 2011.

Okay, so no big deal, right? I’ll just upgrade to a supported version. However, once your flavor gets too far out of support, it turns out that the baked-in upgrade tools don’t work so well any more, and you have to do some extra gymnastics. Specifically, some of the packages you need in order to upgrade get kicked off of http://releases.ubuntu.com and moved to http://old-releases.ubuntu.com, so you have to edit /etc/apt/sources.list to include some references to the Ubuntu retirement home. The basic process is described on the Ubuntu “End of Life” upgrade page, and Google-fu will reveal a number of helpful tutorials on the subject.

I did the things prescribed in the above-linked EOL upgrade instructions, but when I went to install the new version of update-manager-core in preparation for the upgrade, I was met with a raft of 404 errors. I re-read the instructions, Googled like crazy, ran apt-get using every switch imaginable, and even sprinkled some goat’s blood on my keyboard (#offensive!), but I still couldn’t get it to work. I got pretty frustrated, especially because I don’t have much depth in this area, and am ill-equipped to problem solve if the cookbook approach fails.

After some swearing and deliberation, I finally did something that may seem common-sensical but which was not at all obvious to me. In fact, when I did it, I thought I was throwing up a Hail Mary. I had already added the required sources in /etc/apt/sources.list, as below:

## EOL upgrade sources.list
# Required
deb http://old-releases.ubuntu.com/ubuntu/ karmic main restricted universe multiverse
deb http://old-releases.ubuntu.com/ubuntu/ karmic-updates main restricted universe multiverse
deb http://old-releases.ubuntu.com/ubuntu/ karmic-security main restricted universe multiverse

# Optional
#deb http://old-releases.ubuntu.com/ubuntu/ karmic-backports main restricted universe multiverse

So, on what I thought was a long shot, I commented out the corresponding entries for releases.ubuntu.com, and gave it a whirl again. To my surprise, that was the special sauce I needed, and the update manager refresh proceeded without a hitch. (If only that were true for the rest of my upgrade, but that’s a tale for another time.)

So, maybe that last part was laughably obvious to some, but it certainly wasn’t obvious to me (how should I know what kind of search chain is being used?), and I hadn’t seen it in any of the “cut and paste” cookbooks I had consulted. Hopefully, some other Linux-inept schmuck will read this and be spared some of my torments.