> Interesting. We have had Sun fileservers since the dawn of afs and we have
> never had any filesystem corruption. Were you running the multiple processor
> machines before AFS was properly MP certified way back?
> Mark Giuffrida
> University of Michigan, CAEN
Let me see if I can elaborate more on what Randall was saying. Here
at the University of Maryland our primary fileserver collection has
always been Sun hardware. We have 15-20 fileservers, all which are
Suns. The problem we have been observing only affects Solaris 2.5,
2.5.1, and 2.6 fileservers, and only under conditions of heavy usage.
All of the fileservers are single processor machines, SPARC 5s and 10s.
We have been in contact with both Transarc and Sun on this problem for
18 months now, and the consensus is that the problem lies in Sun's ufs
drivers. We are currently in the process of setting up test hardware
so that we can work with the Sun engineering team to get the problem
fixed.
The corruption appears in the form of hundreds of duplicate inodes and
will eventually cause the server to kernel panic with messages like
"freeing free frag" or "freeing free block". The corruption damages
volume headers as well as user data. We haven't yet been able to
duplicate the problem other than by observing our live filesystems.
We originally observed the problem on our RAID arrays, but we have
also seen it on ordinary disks as well.
Up until recently we were the only site that had reported this
problem, but I believe there is now another site that is seeing
similar corruption.
Our only solution to the problem so far has been to replace our Sun
hardware with DEC Alphas, which run just fine.
Kevin Hildebrand
University of Maryland, College Park
