Vault 2016

Replication is an important aspect of any storage solution for backing up data and ensuring High Availability. This is non-trivial in case of distributed systems because achieving consistency and HA with only 2x replication is difficult as there is no notion of quorum (majority voting). But not everyone can afford to store 3x copies just to achieve consensus in case of a disagreement. So they end up using 2x replication but face frequent split-brains due to flaky networks etc. - a common complaint on the gluster-users mailing list.

The presentation will focus on the arbiter configuration in glusterFS replica volumes and explain how it provides the same consistency guarantees as that of a full blown 3 way replica but without the 3x storage cost. It describes how the arbitration logic works to prevents files from ending up in split-brain, how to deploy and monitor them.