Is it possible to stretch a cluster over two sites/subnets, or can I create two separate clusters and configure them to communicate in someway for replication and migration? For example... a primary site and a DR site.
multi cluster setup
- Thread starter coreybrett81
- Start date
While you can configure a setup of two sites, it is not recommended. There are factors like fail-over, latency, quorum, that have to be taken into account. Corosync needs a steady low latency link to keep the cluster working stable. With two sites, there needs to be a third site for quorum. Which site takes precedence if one site is down, but seen by the third? Fail-over is more a "manual" process, as there is no inter-cluster awareness that has a state of which VM is where.
Depending on technology the storage can be replicated to a different site. Ceph (rbd-mirror)/ZFS (pvesr) allow replication to different clusters/hosts.