Replay queue length is slowly settling down on 1 DAG node

Question

Hi,

Consider 2 nodes in Exchange 2019 DAG. In one of the node RQL is settling down for 20mins. While on the other it settles down quicker. This happens for all the copies in the affected Mailbox server. Get-mailboxdatabasecopystatus shows some actual delay in Replay lag status for the affected copies in the affected mailbox server.

ReplayLagStatus                         : Enabled:False; PlayDownReason:None; ReplaySuspendReason:None; Percentage:0; Configured:00:00:00; MaxDelay:1.00:00:00; 
                                          Actual:9.05:58:57

Any help to start troubleshooting for the RQL issue would be appreciated.

Cheers

Priya

Answer 1

@Priya Jayaraman ,

Hi, welcome to post our Q&A forum!

Based on the information you provided, it seems that there is a delay in the replay queue length for the affected copies in the affected mailbox server. The replay queue length indicates the number of log files waiting to be replayed into this copy of the database.

There could be several reasons why the replay queue length is settling down slower on one node than the other. One possibility is that there is a network issue between the two nodes, which is causing replication delays. Another possibility is that there are issues with the network adapters configuration of MAPI and Replication networks.

Does suspending and resuming the passive copy help? Does restarting the Replay service on the passive copy help?

It’s also worth noting that replay lag status can be affected by various factors such as network latency, disk I/O, and CPU utilization.

I suggest you check your network configuration and run some diagnostic tests to identify any issues.

https://learn.microsoft.com/en-us/exchange/high-availability/manage-ha/configure-db-properties?view=exchserver-2019&redirectedfrom=MSDN

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