When deleting machines that were created and provisioned through the vRealize Automation service catalog, as a best practice, use a workflow or the Destroy action available in vRealize Automation, rather than deleting the machine through Horizon Administrator or vSphere Web Client.
If a vRealize Automation-provisioned machine is deleted from within Horizon Administrator, the machine status on the Infrastructure tab in vRealize Automation appears as Missing. For this reason, consider using a machine-naming convention that indicates whether the machine provider is vRealize Automation or Horizon.
If this situation occurs, the remedy is to use the Destroy action on the Infrastructure tab in vRealize Automation. Whenever an administrator or delegated administrator uses the Destroy action, the virtual machine is removed from the Horizon desktop pool and the virtual machine is deleted.
To use the Destroy action, the tenant administrator or delegated administrator must have delegated administrator access on the pool that the machine belongs to. To add a tenant administrator or delegated administrator to the group of delegated administrators for the pool, run the Add Delegated Administrator Configuration workflow, as described in Assign Delegated Administrators to Pools. To determine which pool a machine belongs to, you can look on the Properties tab for the machine on the Infrastructure tab in vRealize Automation.
When you use the Destroy action, the vcac-desktop-callback workflow is run in vRealize Orchestrator. This workflow is located in the Horizon/CoreModules/Business Logic folder. To monitor the action, you can log in to Orchestrator and view the logs for the workflow run. You can also monitor progress in vRealize Automation, by clicking the machine item on the tab, The status goes from InitializingRequest to UnprovisioningMachine, to Disposing, and finally the machine is removed from the list.