Re: Fiendishly expensive
Duncan I have a lot of respect for you but here you are being disingenuous at best.
Look at the first paragraph on Cormac's design guide that is on the VSAN product page....
The minimum configuration required for Virtual SAN is 3 ESXi hosts. However, this
smallest environment has important restrictions. In Virtual SAN, if there is a failure,
an attempt is made to rebuild any virtual machine components from the failed
device or host on the remaining cluster. In a 3-node cluster, if one node fails, there is
nowhere to rebuild the failed components. The same principle holds for a host that
is placed in maintenance mode. One of the maintenance mode options is to evacuate
all the data from the host. However this will only be possible if there are 4 or more
nodes in the cluster, and the cluster has enough spare capacity.