Three child resource pools exist for a DRS cluster. One of these resource pools has been configured with a CPU reservation of 21GHz and a memory reservation of 21GB. The pool has eight single-processor virtual machines and two dual-processor virtual machines. Each of these virtual machines has a CPU reservation of 2GHz and a memory reservation of 2GB. An administrator is unable to power on all virtual machines in the pool.
Which two steps can be taken to resolve the issue while minimizing the amount of extra resources reserved by the pool? (Choose two.)
A.
Increase the amount of CPU and memory resources in the pool to meet virtual machine requirements.
B.
Increase only the memory resources in the pool to meet virtual machine requirements.
C.
Remove the expandable reservation option from the parent pool.
D.
Remove the expandable reservation option from the sibling pools.
Does anybody know why A and D?
10 VMs, it is reservation of 20 Ghz of CPU and 20 GB of RAM.
1 GB – it should be enough for memory overhead, shouldn’t it?
;-(
In my opinion, this question is poorly worded and leaves a lot to be left open for interpretation, but process of elimination can give you the two answers that you see.
2 of the VM’s are dual processor machines, so a 2GHZ reservation for each processor would be 4GHZ for those 2 VM’s and a total of 24GHZ for all of the VM’s in the pool. There is not enough CPU resources in the child pool to fulfill this. We need to assume that either the expandable reservation option for the child pool is not selected, or that it is selected and there are simply not enough resources to give it additional CPU resources.
You are correct about memory, it shouldn’t be a limiting factor. According to http://pubs.vmware.com/vsphere-50/topic/com.vmware.ICbase/PDF/vsphere-esxi-vcenter-server-50-resource-management-guide.pdf page memory overhead should be between 30MB and 50MB per VM, so not enough to be a concern.
So:
A – Possibly. If it’s referring to the parent pool, and the child pool has the expandable reservation option selected, increasing the amount of resources in the parent pool will leave more resources available for the child pool and therefor it’s VM’s to reserve if need be.
B – No. Memory is not an issue so it’s not going to help.
C – No. An expandable reservation on the parent pool may help in this situation, but turning it off would certainly not help the situation.
D – Possibly. If the sibling pools have expanded their reservations beyond what was given to them, they would be using additional resources which might stop the child pool in question from reserving additional resources. Removing the sibling expandable reservations could free up additional resources in the parent pool, allowing the child pool in question to reserve additional CPU and power on it’s VM’s.
So, 2 answers need to be selected, since B and C are definite No’s, A and D are the only possible choices.
How do you come to 24GHz total CPU for the pool, 8 VM’s at 2GHZ each would be 16GHz plus the 4GHz for the 2 dual-processor VM’s, totaling 20GHz. Pool has enough reservation for CPU.
Answer should be B and D