[Lustre-discuss] MGS - one per site

[Andreas Dilger]

On Jun 26, 2009  10:52 -0500, Carlos Santana wrote:
> Can a lustre file system have more than one MGS? Isn't it only one per
> site? I saw some examples where target type mgs was mentioned during
> mkfs.lustre for MDS and OSS nodes. Is it correct and when is it used?

It makes sense generally to have a single MGS per site for multiple
filesystems, because if clients are mounting more than one filesystem
they can only communicate with a single MGS at a time.

In some cases there will of course be a need for multiple MGSes in
a single site (e.g. secure and open networks), which is fine as long
as clients don't try to mount from multiple MGSes at once.

Cheers, Andreas
--
Andreas Dilger
Sr. Staff Engineer, Lustre Group
Sun Microsystems of Canada, Inc.