We have a problem that started after we consolidated VirtualCenters between sites. The problem is that Cluster Administrators are unable to power on VMs. When a Datacenter Administrator logs in, he is able to power on the VM. Also, the cluster administrator can power on the VMs if DRS is disabled on the cluster.
so you must combine with permissions. Maybe Resource->Migrate/Relocate is needed to be checked. Seems that permissions of Cluster Administrators role does not have permissions to place VMs on different hosts (what DRS wants to do)
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But the problem shouldn't just go away when DRS is enabled.
like you said, that this problem does not occur, when DRS is disabled, it means, that this could be related to vm migration permissions, because while DRS is enabled, it will try to migrate powered on VM to some ESX in the cluster (and for this operation it seem not to have permissions). So take a look into permissions I advised.
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