Purpose
Disabling Parent VMs through the Horizon UI for a particular VC will result in the parent VMs getting disabled for all the clusters present in that deployment.While this may be desired in some cases, some customers will want more control over having the ability to selectively disable this for specific clusters only, for instance, those undergoing upgrades.
This is also relevant when you have vTPM-enabled instant clone pools in your deployment. Parent VMs could be disabled on vTPM-enabled instant clone pools in the following scenarios:
In the case of dedicated vTPM-enabled instant clone pools, Set 'refresh on logoff' to 'NEVER' and avoid any push image workflows during the upgrade window. In the case of floating vTPM-enabled instant clone pools, arrange a dedicated upgrade window where new VMs are not provisioned.
However in other cases, while upgrading a vSphere environment using VMware vSphere Update Manager (VUM), you may want to skip some clusters from entering maintenance.
Such cluster(s) including the ones that accommodate the vTPM-enabled instant clone pools can skip maintenance during the VMware vSphere Update Manager (VUM) upgrade.This can be achieved by using the custom attribute InstantClone.SkipMaintenance on each cluster for which maintenance is to be skipped.
Resolution
Log into the vSphere UI.Navigate to the Hosts and Clusters view.Select the cluster for which maintenance is to be skipped.Under the Summary tab, within the Custom Attributes tile, assign the value 1 to the custom attribute InstantClone.SkipMaintenance.Repeat steps 3 and 4 for every cluster for which maintenance is to be skipped.Wait a few minutes and then disable ParentVms through Horizon UI.
At this point only clusters that do not have InstantClone.SkipMaintenance set will get their parent VMs cleaned up. Those clusters are now ready to undergo upgrades using VUM. Resetting InstantClone.SkipMaintenance on a cluster will cause the parent VM cleanup to be triggered if the parentsVms are still disabled. For the cluster that has vTPM enabled instant clone pool, you could enable maintenance on a per-host level, see Entering and exiting maintenance mode for an ESXi host that has Horizon instant clones and then upgrade the hosts individually.Note: If some Parent VMs do not get deleted while toggling the Disable Parent VMs switch to on, toggle the switch again in some time.
Related Information
This KB is referenced in Documentation: Perform Maintenance on Instant-Clone Hosts Page last reviewed: October 2023Next review due: December 2023
