[CentOS] who uses Lustre in production with virtual machines?

Wed Aug 4 13:13:58 UTC 2010
Todd Denniston <Todd.Denniston at tsb.cranrdte.navy.mil>

Emmanuel Noobadmin wrote, On 08/03/2010 11:13 AM:
> From what I understand, I cannot do the equivalent of network RAID 1
> with a normal DRBD/HB style cluster. Gluster with replicate appears to
> do exactly that. I can have 2 or more storage servers with real time
> duplicates of the same data so that if any one fails the cluster does
> not run into problem. By using gluster distribute over pairs of
> server, it seems that I can also easily add more storage by adding
> more pairs of replicate server.

To have more than one active server with DRBD (or other disk type shared between active machines)
you need to be using a file system which supports shared disk resources.
http://www.drbd.org/docs/about/
http://www.drbd.org/users-guide-emb/s-dual-primary-mode.html
http://www.drbd.org/users-guide-emb/ch-gfs.html
http://www.drbd.org/users-guide-emb/ch-ocfs2.html

and perhaps using Gluster (Raid0 on net) with DRBD (Raid 1 on net) as disk space to get HA into Gluster?
http://www.drbd.org/users-guide-emb/ch-xen.html

Note that it has been a while since I have ran DRBD on a set of systems and I only ran in
active-passive with ext3, so I only know about the resources above that someone would want to look at.
-- 
Todd Denniston
Crane Division, Naval Surface Warfare Center (NSWC Crane)
Harnessing the Power of Technology for the Warfighter