Pacemaker supports practically any node redundancy configuration including Active/Active, Active/Passive, N+1, N+M, N-to-1 and N-to-N.

Active/passive clusters with two (or more) nodes using Pacemaker and DRBD are a cost-effective high-availability solution for many situations. One of the nodes provides the desired services, and if it fails, the other node takes over.

Pacemaker also supports multiple nodes in a shared-failover design, reducing hardware costs by allowing several active/passive clusters to be combined and share a common backup node.

When shared storage is available, every node can potentially be used for failover. Pacemaker can even run multiple copies of services to spread out the workload.