Going from 3*(2+1) to 3*(3+1) glusterFS

[akanugan]

I have a gluster volume like:

Volume Name: ovirt
Type: Distributed-Replicate
Volume ID: xyzzy
Status: Started
Snapshot Count: 0
Number of Bricks: 3 x (2 + 1) = 9
Transport-type: tcp
Bricks:
Brick1: ovirt1:/data/brick1/gv0
Brick2: ovirt2:/data/brick1/gv0
Brick3: ovirt4:/data/brick1/gv0 (arbiter)
Brick4: ovirt4:/data/brick2/gv0
Brick5: ovirt1:/data/brick2/gv0
Brick6: ovirt2:/data/brick2/gv0 (arbiter)
Brick7: ovirt2:/data/brick3/gv0
Brick8: ovirt4:/data/brick3/gv0
Brick9: ovirt1:/data/brick3/gv0 (arbiter)

If I need to add a new node (ovirt3 with 3 bricks), I read that in some old docs, I can't have more than 2 data replicas? To add extra redundancy and to be able to use the bricks from ovirt3, I am looking for suggestions. The options that came to my mind was:

1. Probably I can remove the arbiter (promoting that to full replica) and add new bricks from ovirt3? [3 x (2 + 1) --> 3x 4]. Not useful I guess? No quorum rules can be established
2. I think I can do 4 x (2 + 1). In this case, the 4th replicated set would be (2 + 1) with all bricks on ovirt3 --> No HA
3. Ideally I would like to have the option of 3 x (3 + 1). Like just have all the new bricks to be data replica with the rest of the other bricks as it is now.

Any suggestions on option 3 would be greatly appreciated. Thank you!