High availability and the compute cluster

Management node high availability (HA) and the compute cluster are tightly coupled, so changing nodes in one usually affects the other. Take note of the following:

• Each node in the HA configuration must meet the requirements for the management node listed in the Server requirements. If the compute cluster is to be created, its hardware requirements must be added as well.
• If the HA configuration has been created before the compute cluster, all nodes in it will be added to the compute cluster.
• If the compute cluster has been created before the HA configuration, only nodes in the compute cluster can be added to the HA configuration. For this reason, to add a node to HA configuration, add it to the compute cluster first.
• If both the HA configuration and compute cluster include the same three nodes, single nodes cannot be removed from the compute cluster. In such a case, the compute cluster can be destroyed completely, but the HA configuration will remain. This is also true vice versa, the HA configuration can be deleted, but the compute cluster will continue working.