[Gluster-users] to RAID or not?

[Gandalf Corvotempesta]

2016-07-04 19:35 GMT+02:00 Russell Purinton <russell.purinton at gmail.com>:
> 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.

3 servers is just to start. We plan to use 5 server in shorter time
and up to 15 on production.

> 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.

So, any disk failure would me at least 6TB to be recovered via
network. This mean an high network utilization and as long gluster
doesn't have a dedicated network for replica,
this can slow down client access.