Recently we have had issues with our DAG setup.
After reboot of the mail servers, I noticed that the Cluster Service was not started. I started it, however, DAG is still not functioning.
When I open the Failover Cluster MMC and click Start Cluster Service, it takes a long time, so I have to cancel the start at about 2:30 minutes.
In looking at the event logs, I see event ID 1573 for FailOverClustering: Node 'servername' failed to form a cluster. This was because the witness was not accessible. please ensure that the witness resource is online and available.
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