Which two circumstances might cause a DRS cluster to become invalid? (Choose two.)
A.
A reservation on a parent pool is reduced while a virtual machine is failing over.
B.
An ESXi host in the cluster has been placed into maintenance mode.
C.
A migration on a virtual machine is attempted while the virtual machine is failing over.
D.
Virtual machines have been powered on from a vSphere Client connected directly to an ESXi host.
http://pubs.vmware.com/vsphere-50/index.jsp?topic=%2Fcom.vmware.vsphere.resmgmt.doc_50%2FGUID-8C04BAA0-45BD-4484-BAB3-CE6FD24FEB0E.html
A cluster becomes invalid if the user reduces the reservation on a parent resource pool while a virtual machine is in the process of failing over.
Is this a feature or a bug?