Our Hosts may have a single point of failure for storage so, I wanted to understand exactly what would happen if storage connectivity was lost. I have researched this in the past and, at the time, the answer was that HA is not triggered and the VMs on the Hosts are in a strange, powered on, unstable state until manual intervention. I wanted to see if this still holds true or if there have been changes with more recent versions of ESXi.
In case you are running IP based storage, it is highly recommend to configure the isolation response to: power-off and All hosts in the HA cluster must have access and visibility to the same shared storage; otherwise, they would have no access to the VMs.
Let me know if you still have any question
My question is specific to fiber channel storage and I have separately confirmed that this behavior has not changed. A Host disconnected from storage does not alone trigger any isolation response or automatic action. VMs on that Host will still continue to run in memory in a precarious state (disconnected for storage) until manual intervention or until storage connectivty is restored.