Virtual machines in a linked clone group can be part of a VMware HA (high availability) cluster. The number of hosts in a cluster might affect HA’s ability to restart a failed virtual machine.

  • Clusters that contain ESXi 5.0 or earlier hosts – If a cluster has eight or fewer hosts, then linked virtual machines restart properly. However, if the cluster has more than eight hosts and any of the hosts are ESXi 5.0 or earlier, HA might not be able to restart a virtual machine after it fails. HA is not aware that virtual machines in the linked clone group are subject to the eight host limit. In this case, when HA responds to a failure, it might try to restart the virtual machine on a host that cannot participate in the group due to the maximum host limit. HA will attempt failover five times to different hosts. Thus, in clusters with 13 or more hosts, it is possible that HA will never try a host that is associated with the linked clone group.
  • Clusters that contain only ESXi 5.1 or later hosts – The maximum host limit for a linked clone group is the maximum number of hosts allowed in a cluster. In this case, the number of hosts in the cluster does not affect the ability to restart failed virtual machines.