DAG File share witness issue in multiple DAG environment for Exchange server

Question

Hello expertise,
I have an Exchange Server environment with Exchange Server 2016, consisting of two mailbox servers in the DC site and two in the DR site, configured in a DAG named "dag01." Currently, I am migrating to Exchange Server 2019. As part of the migration, I have deployed a similar setup with two mailbox servers in the DC site and two in the DR site for Exchange 2019, with a new DAG named "dag02." Both DAGs are IP-less and exist in the same Active Directory forest, but with different witness servers and directories, and the mailbox servers and databases are separate from the Exchange 2016 environment.

After configuring the new DAG (dag02) in the Exchange Server 2019 environment, it appears to be working correctly. However, when I run the following command:

Get-DatabaseAvailabilityGroup -Status | ft Name, Witness, Servers*

I get the following output:

For dag01:

WitnessShareInUse : None

For dag02:

WitnessShareInUse : Primary

Previously, dag01 had its WitnessShareInUse status set to "Primary." Additionally, the VerifyShareWriteAccess.txt and Witness.log files are missing from GUID folder in dag01's witness share after creating dag02.

My questions are:

Why has the status of dag01 changed to "None"?

Does this status change indicate any issues with the functionality of dag01?

How can I set the WitnessShareInUse status to "Primary" for both DAGs, or how can I resolve this issue?

Answer 1

Hi @Dipto Adhikary,

Welcome to the Microsoft Q&A platform!

According to your description,The status of the WitnessShareInUse for dag01 changing to "None" and the files being missing from the witness share directory may indicate that there is an issue with the witness server configuration or that the witness server for dag01 is no longer being used.

Here are some steps you can follow to diagnose and potentially resolve this issue:

1. Ensure that the witness server for dag01 is correctly configured and reachable. You can do this by running the following command to check the current witness server settings:

      Get-DatabaseAvailabilityGroup dag01 | Format-List Name, WitnessServer, WitnessDirectory
   

2. Ensure that the witness server and witness directory for dag01 are accessible from all nodes of the DAG. Test connectivity and permissions to the witness share:

      Test-Path \\<WitnessServer>\WitnessDirectory
   

   Replace <WitnessServer> and WitnessDirectory with the actual server name and directory path.
3. Manually check the witness server to see if the VerifyShareWriteAccess.txt and Witness.log files exist in the witness directory for dag01.
4. If the witness share is not correctly created, you may need to reconfigure it. You can set a new witness server or the existing one again using:

      Set-DatabaseAvailabilityGroup -Identity dag01 -WitnessServer <WitnessServer> -WitnessDirectory <WitnessDirectory>
   

5. In some cases, restarting the DAG members can help to reset the state and reconfigure the witness server properly.
6. Always ensure the overall health of the DAG is good. Use the following command to check the health status:

      Test-ReplicationHealth -Identity dag01 
      Test-ReplicationHealth -Identity dag02
   

Notes:

1. The WitnessShareInUse status being "Primary" indicates that the witness is being used as the primary witness server for the DAG.
2. Each DAG will have its own witness server and directory, so setting both to "Primary" isn't typically necessary or possible as it relates to their individual usage statuses.

Please feel free to contact me if you have any queries.

Best,

Jake Zhang