On Wed, 2008-01-23 at 21:51 -0500, Jeff Wasilko wrote: > On Wed, Jan 23, 2008 at 02:20:44PM -0500, Lon Hohberger wrote: > > On Tue, 2008-01-22 at 16:18 -0500, Jeff Wasilko wrote: > > > On Tue, Jan 22, 2008 at 03:59:47PM -0500, Christopher Hawkins wrote: > > > > If you don't need GFS... Then drbd + heartbeat is a good way to go if > > > > you > > > > want to mirror the local storage on each machine. > > > > > > True, except Zimbra has explicit support for RHCS, and we'd be off > > > rolling our own solution with drbd + heartbeat.... > > > > As I recall, you can use LVM mirroring. In recent versions of RHCS (4.6 > > maybe?), there's an agent to handle assembly/disassembly of LVM > > (non-clustered) volume groups before/after failover. > > I found the 4.6 docs, and it does look like all of the previous > warnings about using mirrors under cluster are gone. > > Plus, I saw this note in the 4.6 release notes: > > # > A known device mapper issue causes unexpected cmirror deadlocking. This issue > prevents reliable use of cluster mirrors configured with three or more legs. > As such, it is advised that you avoid configuring cluster mirrors with three > legs or more until this issue is resolved. > # > > Is cmirror the layer below lvm? > > We generally don't do 3-way mirrors, other than when we're transitioning > between arrays on the SAN.
Just to stress - You need to use cmirror, not plain LVM mirror, and clvm - not plain LVM (there are docs somewhere about changing the locking type in lvm.conf) -- Lon -- Linux-cluster mailing list [email protected] https://www.redhat.com/mailman/listinfo/linux-cluster
