Changes to /etc/mysql cause installation failure

[Lars Tangvald]

We get a fair amount of installation failures due to issues with the contents of /etc/mysql, such as /etc/mysql/my.cnf.fallback being missing when it's set up with alternatives.

The most common cause seems to be deleting /etc/mysql after removing (not purging) packages, resulting in files not being rewritten there when trying to install.

The workaround is to run apt-get purge mysql-common to clear out the conffiles properly, then reinstall.

Might be related to LP: #1602945

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Robie Basak (racb)]

I got the impression that it was caused by users trying to fix up other things by attempting to remove /etc/mysql completely and then reinstalling, but not purging and reinstalling mysql-common as part of that process. But sure - that might not be the only cause, so if you think it's worth investigating then we should.

[Lars Tangvald (lars-tangvald)]

Yes, I haven't been able to reproduce this without manually changing /etc/mysql.
But it might be worth adding a check on the result of the alternatives-command and having it suggest purging and reinstalling mysql-common if there's a failure?

[Robie Basak (racb)]

Sure, that's a good idea.