Hi Simone,

> According to gluster administration guide:
> https://docs.gluster.org/en/latest/Administrator%20Guide/Network%20Configurations%20Techniques/
>  
> in the "when to bond" section we can read:
> network throughput limit of client/server \<\< storage throughput limit
>
> 1 GbE (almost always)
> 10-Gbps links or faster -- for writes, replication doubles the load on the network and replicas are usually on different peers to which the client can transmit in parallel.
>
> So if you are using oVirt hyper-converged in replica 3 you have to transmit everything two times over the storage network to sync it with other peers.
>
> I'm not really in that details, but if https://bugzilla.redhat.com/1673058 is really like it's described, we even have an 5x overhead with current gluster 5.x.
>
> This means that with a 1000 Mbps nic we cannot expect more than:
> 1000 Mbps / 2 (other replicas) / 5 (overhead in Gluster 5.x ???) / 8 (bit per bytes) = 12.5 MByte per seconds and this is definitively enough to have sanlock failing especially because we don't have just the sanlock load as you can imagine.
>
> I'd strongly advice to move to 10 Gigabit Ethernet (nowadays with a few hundred dollars you can buy a 4/5 ports 10GBASE-T copper switch plus 3 nics and the cables just for the gluster network) or to bond a few 1 Gigabit Ethernet links.

I didn't know that.
So , with 1 Gbit network  everyone should use replica 3 arbiter 1 volumes to minimize replication traffic.

Best Regards,
Strahil Nikolov