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 directiy to an ESXi host
Correct answer: A,D
The DRS becomes invalid if:
1. A cluster might become overcommitted if a host fails.
2. A cluster becomes invalid if vCenter Server is unavailable and you power on virtual machines using a vSphere Client connected directly to a host.
3. 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.
4. If changes are made to hosts or virtual machines using a vSphere Client connected to a host while vCenter Server is unavailable, those changes take effect. When vCenter Server becomes available again, you might find that clusters have turned red or yellow because cluster requirements are no longer met.
I agree, A snd D. This question is also part of VCP 510 exam questions here.