2012-03-13

Ubuntu: LTS to LTS+1 upgrade leaves cruft

Over the past few weeks, I upgraded my Ubuntu hosts to the Precise release due to be published next month. While the upgrade on my desktops from Oneiric to Precise went mostly well, the upgrade of my terminal server from Lucid to Precise was more daunting. In short: too many packages leave an undue amount of cruft behind, namely tons of obsolete configuration files that are not correctly handled by maintainer scripts, to either delete obsolete files or to rename them to the currently valid filename. At Debian, these oversights are periodically monitored using piuparts and reported to the package maintainer, but Ubuntu doesn't seem to offer this sort of automated Quality Assurance process yet. Perhaps this would be something worth developing?

PS: For those who wonder how I spotted those obsolete configuration files, I simply enabled the FLAUSCH environment variable before running upgrade-system.

4 comments:

MagicFab said...

Hi Eric, thanks for sharing this bit of information. I was intrigued by this fleece variable you used :)

Here's what the manpage[1] says:

FLAUSCH
Setting this variable enables various extremely pedantic purge options.
This feature is totally experimental; usage is strongly discouraged and
should only be attempted by truly experienced Debian administrators. It
can be used to sanitize a Debian system after a distribution upgrade or
to detect packages that don't conform to the Debian Policy. Setting the
variable as a command line environment, only when needed, is considered
a safer approach than adding it to upgrade-system.conf variables.

[1] http://manpages.ubuntu.com/manpages/precise/man5/upgrade-system.conf.5.html

Marius Gedminas said...

What is 'upgrade-system'? The only official supported Ubuntu upgrade tool is 'do-release-upgrade' (or 'update-manager' if you want a GUI).

N said...

Eric, I'd love to talk to you more about your experiences. Since you encountered some leftover packages, I'd like to get your feedback on the upgrade in general and then get issues you found fixed :-) Feel free to contact me using any email/IRC https://launchpad.net/~nskaggs

tumbleweed said...

Yes, I'd like to run piuparts on Ubuntu. Unfortunately, our release upgrade process is different (one can't just dist-upgrade, there are quirks that only update-manager can handle).

That, and we don't have much infrastructure outside Canonical. Someone would have to run it on their own machine.Yes, I'd like to run piuparts on Ubuntu. Unfortunately, our release upgrade process is different (one can't just dist-upgrade, there are quirks that only update-manager can handle).