3. The Cluster Layer

Pacemaker utilizes an underlying cluster layer for two purposes:

• obtaining quorum
• messaging between nodes

Currently, only Corosync 2 and later is supported for this layer.

This document assumes you have configured the cluster nodes in Corosync already. High-level cluster management tools are available that can configure Corosync for you. If you want the lower-level details, see the Corosync documentation.