Reset log sequence for the Database which is part of DAG in Exchange Server 2010.

You might end up in resetting log sequence for some reasons, which might be for fixing your backup issues, reseeding issues or due to running out of log sequence (which is a rare case).

It’s easy to reset for standalone database, just you need to rename the log directory after dismounting the database and create an empty folder with same name then mount the database back. Simple right, then how will you do it for the database which is part of the DAG.

I can remove the passive copy and do it for the standalone database, and then I can seed it if I want. But my database size was more than ~500 GB, I did not want to seed my whole data again. Hence I followed this and it worked like a charm.

Here you go:

  1. Dismount the Active database
  2. Suspend the passive database which is healthy (wait for the copy queue length to reduce zero if there are any)
  3. Rename the log directory in active server
  4. Rename the log directory in passive server
  5. Create an empty log directory in active server at the same location
  6. Mount the active copy
  7. Resume the passive copy (log directory will be created in passive server and logs will be copied to that location)
  8. Now you can see your secondary copy as healthy again
  9. Done