Symptoms
When attempting to delete a VM in Horizon that was provisioned from an instant-clone desktop pool, the deletion may fail with the below error:
"A general system error occurred: Fault Cause: vim.fault.GenericVmConfigFault
An error occurred while reverting to a snapshot. One of the disks in this virtual machine is already in use by a virtual machine or by a snapshot."
This can only happen if the VMware NSX product is in use at the same time in the cluster.It will only happen in a small number of random cases since the problem is due to a race condition.
Purpose
This article provides the workaround to mitigate the issue until a permanent fix is available
Cause
The cause is a conflict between internal Horizon VM operations and NSX VM operations on the ESX host.Occasionally, this conflict may corrupt a VDI VM to such an extent that it may seem to run properly, but the VM cannot be deleted or snapshotted.
Resolution
This issue is resolved in VMware ESXi 8.0 Update 2 (build number 22380479)This issue is resolved in VMware ESXi 7.0 Update 3o (build number 22348816)
Workaround
Follow the below steps to workaround the issue until a permanent fix is available.
Delete all existing snapshots on the golden image.Copy the file "namespace.db" (attached) to the golden image VM directory.Edit the golden image config file (which ends in .vmx) to add the following line:
namespaceMgr.dbFile = "namespace.db"
Create new snapshots as necessary and then recreate the instant-clone desktop pools from the golden image.Double-check that the new replica VM(s) that is/are created from the golden image also contain the config file entry.Now, this issue should be avoided for all VDI VMs created from this pool.
