Unable to Remove Host From vCenter
I opened a VMware Service Request yesterday because I ran into a problem that I couldn’t figure out. In one of our environments, we have a 15 host DRS/HA cluster we are migrating from ESX 4 to ESXi 4. The process involves removing the existing ESX host from vCenter before rebuilding the host with ESXi. On two of the 15 hosts, the “Remove” option was greyed out. I first suspected a permissions issue was preventing the hosts from being removed. Though, it didn’t make sense that other hosts in the same cluster were able to be removed and the permissions where identical on the two hosts in question.
I tried disconnecting the hosts from vCenter and then remove–but no success there. I tried re-connecting the hosts to vCenter–still no success. I tried moving the hosts out of the cluster and placing it under the root vCenter object (i.e. the vCenter name)–again no success. I didn’t want to edit the backend database directly before I contacted VMware, so I opened a Service Request. After two days, VMware dug up an existing case that had recently been opened by a customer experiencing the same issue. The only way to cleanly remove the hosts is to create a new temporary cluster, place the hosts in question in this new cluster, and then delete the cluster. This process not only deletes the cluster but it also removes all the hosts underneath the cluster object.
VMware does not yet know what is causing this to occur or how widespread this issue is. They suspect it has something to do with Update Manager and some recent updates. If you run into this condition, it is rare, hopefully this article will help you resolve the problem.
