We have a vCenter 4.0 Server with two ESX 4.0 hosts. We have a vCenter Server 4 Foundation license and a vSphere 4 Advanced 6CPU license. Licenses have been assigned to the server and hosts (each host has two CPUs leaving 2 unassigned on the vSphere license.)
The licenses are applied successfully via the vCenter license management interface, then moments later each host displays the following error on the Summary page:
Configuration Issues License assignment on the host fails. Reasons: The license key can not be assigned.
What causes this error and how can it be resolved?
Have you checked the licenses on VMware's License Portal to make sure the keys you have are the license keys you believe they should be?
Are you making use of any critical features (e.g. Service console on a distributed Switch) that might be disabled if the restrictions associated with your actual license were applied? Is your whole environment operating under eval licenses a the moment?
It turns out we had deployed an older build of ESX to our hosts. Another symptom of this problem was that the vmware-hostd would not start on the hosts after applying all updates via Update Manager.
We rebuilt the hosts with the latest available build. The license error no longer appeared and updates were successfully applied.