I received a call today from a colleague today as he was deploying a new ESXi cluster for a client where 1 of the hosts has the following warning:
"Issue detected on “esx1.domain.local” in “Cluster Name”: Could not reach isolation address: none specified".
The server was up so it definitely wasn’t in isolation mode but I did a few sanity checks to make sure network connectivity wasn’t the problem. After spending 5 minutes or so without finding any configuration error, I went ahead and googled it. Turns out many people have experienced this before and what was missing was the default gateway it the service console settings. Once I put in the default gateway of the address the message went away.