Re: "Invalid client ID" after system lockup and subsequent reset ?

[Stephen Lord <lord@xxxxxxx>]

Karl M. Hegbloom wrote:

> Several times I've had my SMP machine with EVMS and XFS filesystems lock
> up and need to be reset.  After the reboot, sometimes filesystems won't
> mount (it tends to be the "/var" partition) and I must boot to single
> user mode.
>
> When I attempt to mount the filesystem to cause the log replay, it
> refuses to do so, giving an error about an "invalid client id".  I must
> then run "xfs_repair -L" on it to get the machine back online.
>
> What does that error mean, and is there a way to make it mount anyway
> and replay the log?
>
> How can I debug system lockups like that, so that I can give a
> meaningful and useful bug report?  Will someone please work with me in
> private mail (or direct me to the relevant mailing list or
> documentation) and teach me how to debug the Linux kernel, to find
> lockups and such?
This sounds like a corrupted log, the question is, who is doing the 
corruption
here. Bad clientid means there was something in the log which was not
recognized. Since EVMS and XFS have not had a lot of exposure with
each other, I would suspect EVMS is not taking well to the XFS log
writes, they are variable in size, between 512 bytes and 32K, and they
can start on any 512 byte boundary. Not much else in Linux does I/O like
this, possibly EVMS is dropping part of the I/O.

I would raise this on the evms mailing list as well as the xfs one, we can
then work out between us what is going on.

Next time it happens, try xfs_logprint -t /dev/xxx before you mount the
filesystem. It might fail in a similar manner to the kernel though.

Steve