We have a DAG with 3 nodes, after we performed windows update and rebooted all the Exchange servers. There are 2 nodes showing "Down" when we run get-clusternode cmdlet. The mailbox database copy status for all the mailbox servers are showing Healthy/Mounted. However we are unable to do any switchover/mount the database copies on the nodes that are showing down in failover cluster.
There is no firewall in between and the OS internal firewall has been turned off. Other than re-creating the DAG is there anyways then can overcome this?
Any idea guys?