An ESX/ESXi host remediation fails with the error: No supported hosts found for remediate

• The ESX/ESXi host remediation using VMware Update Manager fails
• You see the error:

No supported hosts found for remediate

The operation is not supported on the selected Inventory objects.
Check the events for the objects selected for the operation.

• In the vmware-vum-server-log4cpp.log, located at C:\Documents and Settings\All Users\Application Data\VMware\Update Manager or C:\Users\All Users\VMware\VMware Update Manager\Logs) , you see an error similar to:”[DATE’VciHostRemediateTask.VciHostRemediateTask{14}’ 2276 INFO]  [vciHostRemediateTask, 1313] Skipping [HostName] as it is part of HAC enabled cluster”
• Remediate entry in Events, you see the error:Cannot remediate host “hostname” because it is a part of a HA admission control enabled cluster.

Cause

This issue occurs because the admission control policy that has been set is preventing Update Manager from remediating the host.

vCenter Server uses admission control to ensure that sufficient resources are available in a cluster to provide failover protection and to ensure that virtual machine resource reservations are respected. Admission control imposes constraints on resource usage and any action that would violate these constraints is not permitted. If an automated process needs to take actions, it might temporarily violate the failover constraints. For example, as part of an upgrade directed by VMwareUpdate Manager.

Resolution

To resolve this issue, you can either disable strict admission control or disable VMware HA altogether, put the ESX/ESXi host in the maintenance mode, and then continue with the upgrade.   To disable strict admission control:

1. Right-click the cluster and click Edit Settings.
2. Under Cluster Features, click VMware HA.
3. Under Admission Control, select Disable: Power on VMs that violate availability constraints.
4. Click OK.

To disable VMware HA:

1. Right-click the cluster and click Edit Settings.
2. Under Cluster Features, select Turn off VMware HA.
3. Click OK.
4. Note, once the ESX/ESXi host has been successfully remediated, re-enable VMware HA on the cluster in the event of any future host failovers.