[ovirt-users] Rebooting gluster nodes make VMs pause due to storage error

[nicolas at devels.es]

Hi,

We're using ovirt 3.5.3.1, and as storage backend we use GlusterFS. We 
added a Storage Domain with the path "gluster.fqdn1:/volume", and as 
options, we used "backup-volfile-servers=gluster.fqdn2". We now need to 
restart both gluster.fqdn1 and gluster.fqdn2 machines due to system 
update (not at the same time, obviously). We're worried because in 
previous attempts, when restarted the main gluster node (gluster.fqdn1 
in this case), all the VMs running against that storage backend got 
paused due to storage errors, and we couldn't resume them and finally 
had to power them off the hard way and start them again.

Gluster version on gluster.fqdn1 and gluster.fqdn2 is 3.6.3-1.

Gluster configuration for that volume is:

Volume Name: volume
Type: Replicate
Volume ID: a2d7e52c-2f63-4e72-9635-4e311baae6ff
Status: Started
Number of Bricks: 1 x 2 = 2
Transport-type: tcp
Bricks:
Brick1: gluster.fqdn1:/gluster/brick_01/brick
Brick2: gluster.fqdn2:/gluster/brick_01/brick
Options Reconfigured:
storage.owner-gid: 36
storage.owner-uid: 36
cluster.server-quorum-type: server
cluster.quorum-type: none
network.remote-dio: enable
cluster.eager-lock: enable
performance.stat-prefetch: off
performance.io-cache: off
performance.read-ahead: off
performance.quick-read: off

We would like to know if there's a "clean" way to do such a procedure. 
We know that pausing all the VMs and then restarting the gluster nodes 
work with no harm, but the downtime of the VMs is important to us and we 
would like to avoid it, especially when we have 2 gluster nodes for 
that.

Any hints are appreciated,

Thanks.