[Gluster-users] to RAID or not?

[Russell Purinton]

For 3 servers with 12 disks each, I would do Hardware RAID0 (or madam if you don’t have a RAID card) of 3 disks.  So four 3-disk RAID0’s per server. 

I would set them up as Replica 3 Arbiter 1

server1:/brickA	server2:/brickC	server3:/brickA
server1:/brickB	server2:/brickD	server3:/brickB
server2:/brickA	server3:/brickC	server1:/brickA
server2:/brickB	server3:/brickD	server1:/brickB
server3:/brickA	server1:/brickC	server2:/brickA
server3:/brickB	server1:/brickD	server2:/brickB

The benefit of this is that you can lose an entire server node (12 disks) and all of your data is still accessible.   And you get the same space as if they were all in a RAID10.

If you lose any disk, the entire 3 disk brick will need to be healed from the replica.   I have 20GbE on each server so it doesn’t take long.   It copied 20TB in about 18 hours once.