Consider the following vSAN host configuration:
• Each host contains one vSAN disk group
• All drives in the vSAN disk group are attached to the same storage controller
• All virtual machines are assigned the Virtual SAN Default Storage Policy, which has not been modified
• ESXi is installed on and running from a drive connected connected to a separate storage controller
• vSphere HA is enabled
What happens when the storage controller with the vSAN drives attached fails?
A. All components on the drives affected by the storage controller failure are marked "Offline". vSphere HA restarts all virtual machines running on the host with the storage controller failure.
B. vSphere HA restarts all virtual machines running on the host with the storage controller failure. vSAN components affected by the storage controller failure are marked "Repairing" until the virtual machines are back online.
C. All components on the capacity affected by the storage controller failure are marked "Stale". vSAN waits 60 minutes before attempting to rebuild the affected components on other healthy hosts in the cluster.
D. All components on the capacity affected by the storage controller failure are marked "Degraded". vSAN attempts to rebuild all components affected by the failure on the other healthy hosts in the cluster.
Component Failure State and Accessibility
When a storage controller fails, the components on the flash caching devices and capacity devices in all disk groups that are connected to the controller are marked as degraded.
the answer is D
https://cormachogan.com/2014/12/04/vsan-part-30-difference-between-absent-degraded-components/
To explain the different behaviour, it is important to understand that Virtual SAN has 2 types of failure states for components: ABSENT and DEGRADED.
A component is DEGRADED if Virtual SAN has detected a failure from which it believes the component will not return (e.g. one residing on a failed disk drive)
A component is ABSENT if Virtual SAN has detected a failure, but Virtual SAN believes that the component may re-appear with all data intact (e.g. components residing on disks on an ESXi host has been rebooted)
An ABSENT state reflects a transient situation that may or not resolve itself over time, and a DEGRADED state is a permanent state.
When a component is marked as ABSENT, Virtual SAN will wait for 60 minutes (by default) for the components to become available once again. If they do not become available, and the timer expires, Virtual SAN will begin rebuilding the components elsewhere in the cluster.
DEGRADED components are rebuilt immediately.
There is no component state called Offline, Repairing, or Stale. The answer is D.