[Lustre-discuss] networking problem with kernel-lustre-smp-2.6.9-55.0.9.EL_lustre.1.6.3(1.6.4)smp

[Brian J. Murrell]

On Fri, 2007-12-14 at 18:28 +0300, Anatoly Oreshkin wrote:
> Hello,
> 
> We have Scientific Linux SL release 4.4 (aka RHEL 4.4) with 
> kernel 2.6.9-42.0.3.ELsmp installed on our cluster.

So this is the older RHEL4 kernel.

> I've got from clusterfs site
> http://www.clusterfs.com/downloads/public/Lustre/v1.6/Production/1.6.3/rhel-2.6-i686/
> 
> binary rpms for RHEL-2.6-i686:
> 
> kernel-lustre-smp-2.6.9-55.0.9.EL_lustre.1.6.3.i686.rpm

Indeed, this is the kernel from what I think is RHEL 4.5.

> First  I've tried to test networking with this kernel on NFS file system
> without lustre file system.
> NFS server is started on head node and exports non-lustre file system.
> I've started reading on client nodes NFS file system and encountered
> networking problem.

Did you attempt this exact same test with the SL 4.4
(2.6.9-42.0.3.ELsmp) kernel before using our 2.6.9-55 kernel?  That
would be a most interesting result.  If the problem reproduces with that
kernel then you appear to have a kernel-version independent
hardware/driver problem which you will need to rectify before you can do
anything useful with that node/nic.

If the problem does not exist in the SL 2.6.9-42.0.3.ELsmp kernel, then
the next step would be to try the 2.6.9-55.0.9.ELsmp kernel from SL.  If
the problem does exist in that kernel then there is an issue with the
generic 2.6.9-55.0.9.ELsmp kernel.  If it does not happen with that
kernel either then we have a possible regression in our kernel.  We
cannot determine any of this though without you being able to try those
combinations out.

All of this is expensive in terms of time though, and many times it's
just cheaper to replace troublesome hardware with something that is
known to be working.  It's not as intellectually interesting, but can be
cheaper.  :-)

b.