Recently I stumbled over a weird issue with our Exchange cluster where a Database in the DAG would have 2 copies on 1 server. One copy would be the “Normal / what you expect” database and the other would have a suffix “CNF:<GUID>”
So, what the heck is this. I honestly don’t know but this article seems to suggest that the AD and the Server had an issue at some point and it has been detected as a duplicate. No mail is lost from what I can tell, everything seems fine, just a config seems duplicated.
It looks like this in ECP (sorry for the redaction, but you get the idea)
And in EMS (powershell), it looks like this
NOTE: Get-mailboxdatabase -server blah OR Get-MailboxDatabaseCopyStatus -server blah wont show the CNF DB. You *MUST* specify a DB for it to show in EMS
The annoyance starts when you try and remove it and it wont let you! GAHHH!!!!! The forum post I linked earlier says to use ADSI edit…. but…. you know….. fk that.
The fix i found:
- Add a copy of the DB on another server in the DAG
- Migrate the active copy of the DB to that server
- Remove the copy on the server with the issue.
- You will then be left with just the CNF DB, which you can now remove with
Get-MailboxDatabaseCopyStatus DB01* | where {$_.status -eq "Unknown"} | Remove-MailboxDatabaseCopy - Rinse and repeat for any remaining DBs with the issue
- Reboot the server for good measure (Because Windows…..)
- Add a copy of the DB back to the server
- Migrate the active copy
- Delete the temp copy
- Crack a beer
- ?????
- Profit
Hopefully this helps someone
