question

AndrewNewbold-0477 avatar image
0 Votes"
AndrewNewbold-0477 asked AndyDavid commented

Exchange Hybrid deployment sending out errors for old dismounted databases

I am fairly new to this organization and have inherited a Hybrid Exchange deployment. I have two on-prem Exchange 2013 CU23 servers with dismounted databases that are throwing errors for the databases being corrupted. These databases, apparently, haven't been mounted since 2017, but yet, it is still trying to mount them and access them. Errors 3154, 231, 2006, 3001, and many more. The question is this, did they misconfigure something when moving to the hybrid deployment? Why would the servers still be trying to mount these databases when our mailboxes all reside on O365? Any help at all would be much appreciated. Thank you

office-exchange-hybrid-itpro
5 |1600 characters needed characters left characters exceeded

Up to 10 attachments (including images) can be used with a maximum of 3.0 MiB each and 30.0 MiB total.

AndyDavid avatar image
0 Votes"
AndyDavid answered AndrewNewbold-0477 commented

If they are unmountable, consider simply deleting them then re-creating the arbitration mailboxes on a new, clean database when you mount it.
https://docs.microsoft.com/en-us/exchange/architecture/mailbox-servers/recreate-arbitration-mailboxes?view=exchserver-2019

If ALL the user mailboxes are moved to 365, then all you need is those arbitration mailboxess.

· 2
5 |1600 characters needed characters left characters exceeded

Up to 10 attachments (including images) can be used with a maximum of 3.0 MiB each and 30.0 MiB total.

Awesome, thank you. I think that is exactly what I was looking for. Really just some verification that if I blow the on-prem database away, I am not causing more harm.

1 Vote 1 ·

Just a quick update. I am working on creating a new Database on the secondary server to mitigate down-time. The Secondary Database was completely borked and didn't have any kind of mailbox attached to it except for monitoring.

1 Vote 1 ·
AndyDavid avatar image
0 Votes"
AndyDavid answered AndrewNewbold-0477 commented

Those databases should be mounted:)
Exchange doesnt know your mailboxes are in 365, so I would mount them ( How many?)
This way the arbitration mailboxes can be functional.

If you have more than one database, you can move/verify all the arbitration mailboxes to one DB and remove the other DBs

 Get-Mailbox -Arbitration | New-MoveRequest -TargetDatabase "DBtoKeep"
· 1
5 |1600 characters needed characters left characters exceeded

Up to 10 attachments (including images) can be used with a maximum of 3.0 MiB each and 30.0 MiB total.

We have two mailbox databases. However, like I stated, they have not been mounted since 2017(this is when they migrated). They are very out of date and I believe they are corrupted. Due to the errors mentioned, they will not mount. I have been working throughout today and just found through eseutil they were improperly shutdown. Soft repair failed. Unfortunately the individual who migrated everything is long gone and I have no contact. Thank you for your advice. If I can get them to a healthy state, I will try what you are suggesting. So far, this is a nightmare. I haven't seen anything like this before, but I am more familiar with either O365 or On-prem deployments and not hybrid. Again, thank you for your help.

1 Vote 1 ·
AndrewNewbold-0477 avatar image
0 Votes"
AndrewNewbold-0477 answered AndyDavid commented

I have the secondary server up and running as well as the arbitration mailboxes. Considering the amount of time since these have been healthy, they have not been syncing connectors. Is there an easy way to update server two with the connectors from server one, or is it just the export/import through powershell? Also, thank you AndyDavid for your help.

· 3
5 |1600 characters needed characters left characters exceeded

Up to 10 attachments (including images) can be used with a maximum of 3.0 MiB each and 30.0 MiB total.

you mean the send connectors? Is the source server set to the correct server if so?

1 Vote 1 ·

Yes, on both accounts. We have send and receive connectors on server one that are not currently on server two. In fact there are numerous entries.

1 Vote 1 ·
AndyDavid avatar image AndyDavid AndrewNewbold-0477 ·

Ok, for the receive connector, you would have to recreate on the server that is missing it.
The send connector is org wide, so just ensure all the servers are set as source servers in it.

2 Votes 2 ·