[Linux-cluster] Cluster aware RAID/LVM

[treed-cluster at ultraviolet.org]

I would like to build a highly reliable SAN by having 3 storage nodes
exporting their disk as a block device using AoE and then have the 3
compute nodes each RAID 5 the 3 block devices exported by the storage
nodes so that we end up with one block device, the same block device, seen
by all 3 compute nodes. Then I would like to initialize this as a physical
volume and then create different logical volumes within it with each
compute node mounting a different set of logical volumes.

But my understanding is that this will not currently work because LVM is
not cluster aware. It seems that Linux software RAID is not cluster
aware either.

Perhaps I could use EVMS (which does seem to be cluster aware) on each
of the compute nodes to manage the disk on the storage nodes and then
export a specific volume from each storage node to just one compute node
which would then do RAID 5. This way we have a cluster aware volume
manager exporting volumes to be RAID'd which would only be mounted by
one host each.

Does this sound reasonable?

I would like to avoid the use of GFS anywhere in this particular system
but I might have occasion to use GFS on a different project in the
future. It's been a few years since I have seriously looked into GFS but
it seems to have come a long way towards being usable in a production
environment. I remember it used to have its own volume management. Are
most people doing GFS volume management with EVMS also?

Thanks!


-- 
Tracy Reed
http://ultraviolet.org