Hi, 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 /<one big storage pool for VMs> - 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 characteristics: - 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<fnord> practice, there is. .... Yogi Berra -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
