VMware high availability decreases downtime and improves reliability with business continuity by enabling another ESX/ESXi host to start up virtual machines that were running on another ESX/ESXi host that went down.

High availability is automatically disabled by Zerto Virtual Replication while updating recovered virtual machines in the recovery site from the VRA journal. After the promotion of the data from the journal to the virtual machine completes, high availability is automatically re-enabled.

The HA configuration can include admission control to prevent virtual machines being started if they violate availability constraints. If this is the case, then a failover, test failover or migration of the virtual machines in a VPG to the cluster with this configuration will fail, if the availability constraints are violated when the virtual machines are recovered. It is recommended to test the failover, as described in “Testing Recovery”, on page 331, to ensure recovery will succeed, even when HA is configured with admission control.