configuration questions & advice

configuration questions & advice

am 10.10.2011 17:13:04 von Miles Fidelman


I have a small cluster that I use to host a collection of Xen virtual
machines. I just expanded from 2 nodes to 4 nodes and am looking for
some advice re. configuring a storage subsystem.

The current (2-node) configuration is simple:
- 4 disks per node
- md-based raid10 on each node (separate devices for /boot / swap /
- lvm on the VM storage pool, pairs of logical volumes (/ swap) for each VM
- DRBD to replicate (some) volumes between the two nodes
- (some) VMs set up for auto-failover on node failure (pacemaker, etc.)

In moving to 4 nodes, I'd like to add some flexibility to move VMs
across all 4 nodes, but... that requires using something other than DRBD
to replicate volumes. I'm thinking of something with the following

- 4-node storage cluster (4 drives per node, total of 16 drives in the
storage pool)
- 4-node VM cluster
- using the SAME 4 nodes for both
- note: I've got 4 gigE ports to play with on each box (plan on using 2
for outside access, 2 for storage/heartbeat networking)

I'm thinking of moving to a cluster filesystem (in particular GlusterFS
seems to fit the bill), but it strikes me that an alternative would be to:

- mount all my drives via iSCSI
-- or use RAID10 on each node for /boot / swap, mount the rest of each drive as iSCSI
- build an md RAID10 storage pool that spans all 16 drives across all 4 nodes
- run LVM and build logical volumes on top of that
- build VM migration/failover on top of that (locking, concurrency control, etc.)

Any thoughts re:
- does this make any sense at all?
if so:
- management tools that might make this easier
- clustering layer to manage locking and such?

Thanks very much for any advice and suggestions,

Miles Fidelman

In theory, there is no difference between theory and practice.
In practice, there is. .... Yogi Berra

To unsubscribe from this list: send the line "unsubscribe linux-raid" in
the body of a message to
More majordomo info at