vss writer job failed with Exchange 2019 DAG

[wandbutt]

Hi there,

very often, we have this error in the backup logs of one of the 2 Exchange 2019 servers:

VSS: Backup job failed. Cannot notify writers about the 'BACKUP FINISH' event. A VSS critical writer has failed. Writer name: [Microsoft Exchange Writer]. Class ID:..... Instance ID: ..... Writer's state: ..... Error code: [0x800423f3].


all Exchange services as well as the VSS writer service are restarted 20 minutes prior to the backup process. The Exchanges 2019 run with Standard Server 2022 on a vCenter 7.0.3.01200 and are in a DAG. Since both servers are in same job, they are backed up after each other and not at the same time.

Is there anything we can do about it? I already checked what can be found on the internet in other forums.

Best Regards

[Andreas Neufert]

I have addressed this issue with multiple root causes here:
https://andyandthevms.com/exchange-dag- ... plication/

Check heartbeat setting. You need to change this so that regular VMware processes (vMotion/SvMotion/Snapshots) can complete without forcing the cluster to failover.

Check for Databases that are not mounted and mount them or remove them.

Check my blog above for additional details and general best practices.