DAG member "IS OPERATIONAL "NO"

Question

Having an odd issue, one of my Exchange Servers is showing as not operational in the DAG. There are several errors related to the witness server not being accessible by the alternate witness server? Also getting errors related to a network error. I have checked the server and am not seeing any issues with the network or the Firewall blocking anything. The part that makes no sense is the databases are replicating fine and are all healthy. The server that is having this issue is not the primary, so there are no issues with the DB's. Here are the errors, I obviously changed the names of the servers.

Event ID1564

File share witness resource 'File Share Witness (\alternatewitnesservername.domainname.com)' failed to arbitrate for the file share '\witnesservername.domainname.com'. Please ensure that file share '\witnesservername.domainname.com' exists and is accessible by the cluster.

Event ID 1573

Node 'SERVERNOINDAG' failed to form a cluster. This was because the witness was not accessible. Please ensure that the witness resource is online and available.

Event ID1653

Cluster node SERVERNOINDAG could not to join the cluster because it failed to communicate over the network with any other node in the cluster. Verify the network connectivity and configuration of any network firewalls.

EventID7031

The Cluster Service service terminated unexpectedly. It has done this 67 time(s). The following corrective action will be taken in 60000 milliseconds: Restart the service.

Should I just remove the server from the DAG and re-add or is there something more going on here, as it seems the witness is not accessible.

4 - Exchange 2016 running on Server 2012R2

2 - Witness Servers, one for each DAG

2 - Alternate Witness Servers, one for each DAG for DAC failover.

2 DAG's - servers are in 2 different locations connected via site to site VPN. I have another DAG setup this same way and it working fine.

Any help would be greatly appreciated..

Answer 1

Hi @Gavin Ross ，

Based on the errors you provided, it seems that the witness server is not accessible by the cluster. This could cause the node to fail to join the cluster and the cluster service to terminate unexpectedly.

Possible solution is to change the witness server for the DAG using the Set-DatabaseAvailabilityGroup cmdlet. For example:

Set-DatabaseAvailabilityGroup -Identity DAG1 -WitnessServer <New Server>

You can also check the witness server status in DAG using the Get-DatabaseAvailabilityGroup cmdlet. For example:

Get-DatabaseAvailabilityGroup -Identity “DAG1” -Status | ft Name, Witness*, Servers

Make sure the new witness server meets all the requirements: https://www.stellarinfo.com/blog/fix-exchange-dag-witness-server-failed-state/

Please Note: Since the web site is not hosted by Microsoft, the link may change without notice. Microsoft does not guarantee the accuracy of this information.

I hope this helps. Please let me know if you have any other questions.

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Answer 2

I ran the above command and it does return the correct witness.

Name WitnessServer WitnessDirectory WitnessShareInUse Servers

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DAG1 servername.domain.com C:\WitnessSRV Primary {EXCH01, EXCH02}

I do also see the other server can access the witness no problem.

Answer 3

After a couple weeks of troubleshooting, turns out the issue was the TLS settings on the server. After fixing the setting in the registry, the server was able to join back to the DAG.