[Gluster-users] Question about the number of nodes

[Lindsay Mathieson]

On 19/04/2016 9:55 PM, Kevin Lemonnier wrote:
> As stated in another thread, we currently have a 3 nodes cluster with sharding enabled used for storing VM disks.
> I am migrating that to a new 3.7.11 cluster to hopefully fix the problems with had friday, but since those 3
> nodes are nearly full we'd like to expand.

don't forget to update the opversion for the cluster:

     gluster volume set all cluster.op-version 30710

(its not 30711 as there are no new features from 3.7.10 to 3.7.11)


>
> We have 3 nodes with a replica 3. What would be better, go to 5 nodes and use a replica 2 (so "wasting" one node),
> or go to 6 nodes with still a replica 3 ? Seems like having 3 replicas is better for safety, but can someone confirm
> that whats important for quorum is the number of bricks in a replica set, not the number of nodes total ?
> Would hate to get into a split brain because we upgraded to an even number of node.

Definitely need 3 nodes with replica 3.

You can have a 5 proxmox node cluster with only three nodes being used 
for gluster.

What sort of network setup do you have? mine is relatively low end. 
2*1GB Eth on each node, LACP bonding.

-- 
Lindsay Mathieson