An administrator is implementing deduplication and compression on a vSAN all-flash cluster. -There are 4 nodes in the vSAN cluster.
-Existing VMs use a RAID-5 storage policy
How can deduplication and compression be enabled while permitting the VMs to remain operational?
A. Enable vSAN datastore and encryption.
B. Use explicit fault domains.
C. Use the Allow Reduced Redundnacy option.
D. Enable TRIM/UNMAP.
C
Correct answer is C
A four-node vSAN cluster with RAID-5 objects has no place to move part of the RAID-5 stripe, since RAID-5 objects require a minimum of four nodes. You can still enable deduplication and compression and use the Allow Reduced Redundancy option. This option keeps the VMs running, but the VMs might be unable to tolerate the full level of failures defined in the VM storage policy.
https://docs.vmware.com/en/VMware-vSphere/6.7/com.vmware.vsphere.virtualsan.doc/GUID-125B2B04-FBB9-43AB-8AF9-E7179734BC7C.html