Checking for kernel freshness

[Bernhard Schmidt <berni@birkenwald.de>]

Hi,

the company I work for has a script on SLES/SuSE, that checks the
following three kernel versions

- latest version available in the repository
- version installed in /boot and thus likely to be loaded on next boot
- version running

and warns (and/or fixes) if there is a mismatch. I've been trying to
think of a way to do the same, but failed so far.

Latest version available in the repository is easy enough, just check
for the version the metapackage depends on (or, even easier, check for
updates of the kernel package). 

Checking for the version in /boot is semi-easy (check the package
version installed and hope the user did not fiddle with grub), too.

The hard part seems to be matching the running kernel against the
version installed. I cannot figure out a good way so far. Nothing in the
running kernel seems to show the Debian version (i.e.
2.6.32-41squeeze2), thus I cannot compare it. It is printed in the
bootup messages

[    0.000000] Linux version 2.6.32-5-amd64 (Debian 2.6.32-39squeeze1)
(dannf@debian.org) (gcc version 4.3.5 (Debian 4.3.5-4) ) #1 SMP Mon Jan
9 20:49:59 UTC 2012

but that might be long gone when I check. I could not find this version
string in /proc or /sys yet.

Any idea how to solve that?

Bernhard