System partially unusable after power loss...

[Eric Sandeen]

Manuel Reimer wrote:
> Hello,
> 
> Kernel is 2.6.27.7.
> 
> My Problem started as I got called, that login from KDM is not longer
> possible. In fact, the KDE login is possible, but soon after entering
> the password, a "kbuildsycoca" hangs and takes 100% CPU. Shortly before
> this happened, power was abruptly lost.
> 
> I rebooted to a live CD. As, for some reason, xfs_check was broken on
> that live CD (something with "db" in it was missing), I directly ran

xfs_check is a shell script that invokes xfs_db

> xfs_repair on the broken hard drive and it found some zero byte files

better to run xfs_repair -n rather than xfs_check anyway ...

> and two files with ELF header, which may be (a part of) library files, I
> don't know, as the name wasn't restored.

Having the xfs_repair output would be helpful.

> Is it possible to find out what exactly happened to cause this system to
> be unusable? For me it seems like those restored ELF files are
> something, needed by KDE to start up properly. Why did library files get
> destroyed, the user, using this PC, isn't able to write to? Doesn't this
> mean, they don't get into a write cache and even a power loss can't
> destroy them?

Was there a system software update just prior to the power loss?

Did your storage support IO barriers (i.e. was it lvm or md)?

Buffered data is always lost on a power loss, but I'm not sure
why you should see problems with system files unless they had
just been written out (and not synced).

-Eric

> Yours
> 
> Manuel