Comment 4 for bug 1077740

On 12 November 2012 21:05, v1nce <email address hidden> wrote:
> I'm not sure but I think I tried apt-get install -f before manual installation (with no luck).
> Now when I run apt-get install -f it's ok (0,0,0).
>
> I don't really understand what it complained for as I got all the
> "missing" packages (maybe except for upstart-job (I don't know how to
> query virtual package)).

Although older versions of those packages are installed, the
updated mysql-server states that it requires the more recent
versions, as indicated by the error:

 mysql-server-5.5: PreDepends: mysql-common (>=
5.5.24-0ubuntu0.12.04.1) mais la version 5.5.28-0ubuntu0.12.04.2 est
installée
                   Depends: mysql-client-5.5 (>=
5.5.24-0ubuntu0.12.04.1) mais la version 5.5.28-0ubuntu0.12.04.2 est
installée

The newer packages downloaded (you see them in /var/cache/apt), but
failed to install, presumably due to the disk space error.

>
> I looked at mysql and it was up and running after reboot so i think my
> command was rather safe.

The dpkg command is unsafe is because it ignores the package
dependencies. The program may actually run with the older packages,
and there may not even be any problems, but this can generally not be
assumed, otherwise it would not require particular versions of those
packages.

>
> I know this was a poor bug report (I should have waited before
> trying to fix it myself) so it can be closed anytime because I
> consider it fixed.

I am glad that you fixed your system.

The only issue here really is that apt proceeded with the operation
even though it would fail due to disk space. I believe this is
already reported, and the situation is unlikely to improve much
because this is something very hard for apt to *properly* check.

Generally, it is up to the system administrator to keep disk space
issues under control. Software can not reliably do this for you.

> I reported it because the message 'Depends: foo (>= x) but version y
> is installed' looks odd to me

The first part uses the packaging dependency format as this is the
best way to convey exactly which dependency causes the problem, and
what it's requirements are. Although not the most correct for natural
language, it does read well enough, and changing it is undesirable
because that may lead to ambiguity and make the task of diagnosing
problems (for packagers, developers, people familiar with that syntax)
a bit slower.

Regards