[Lustre-discuss] Modifying Lustre network (good practices)

[Johann Lombardi]

Hi Olivier,

On Thu, May 20, 2010 at 07:12:45PM +0200, Olivier Hargoaa wrote:
> But you couldn't know but we already ran lnet self test unsuccessfully. 
> I wrote results as answer to Brian.

ok. To get back to your original question:

> Currently Lustre network is bond0. We want to set it as eth0, then eth1,
> then eth2 and finally back to bond0 in order to compare performances.
> Therefore, we'll perform the following steps: we will umount the
> filesystem, reformat the mgs, change lnet options in modprobe file,
> start new mgs server, and finally modify our ost and mdt with
> tunefs.lustre with failover and mgs new nids using "--erase-params" and
> "--writeconf" options.

Since you can reproduce the perf drop with LST, you don't need to change
the filesystem configuration to test the different lnet configs. I would
just umount the filesystem, reconfigure lnet by changing the modprobe file
and run LST.

Johann