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We have completed our migration to Exchange online. All mailboxes and public folders have been migrated. However, we have not yet removed the hybrid configuration from AD. We are planning to keep two servers for just SMTP relay and Exchange management.
At this point is it safe for me to delete all monitoring and system mailboxes and remove the databases and the DAG or should I wait until we have removed the hybrid configuration?
Also, for SMTP relay, will I need any of those Exchange mailboxes for any reason? I assume not but wanted to double-check.
I'd like to go ahead and start removing the databases to free up the storage but don't want to break anything with SMTP relay in the process.
Thanks
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Hi @Kenny Stern ，
Just checking in to see how things are going on with this thread. Should the suggestions provided earlier by Andy is helpful, you can click the "Accept Answer" button under his post. If you still have further questions or concerns on this, feel free to post back.
I would leave one database that has all the arbitration mailboxes in that. Reason being, without those mailboxes, you may see errors and auditing wont work.
Not to mention that everytime you update Exchange with a new CU, they will be created again anyway.
You dont need the mailboxes for the SMTP relay part however.
If I deleted all databases how would those mailboxes be created again without a database? Is it just the arbitration ones I should keep? The database that currently holds the arbitration mailboxes is not one of the ones I'm keeping. Do I need to migrate them?
What about monitoring mailboxes? Can those be safely deleted?
Thanks
If there are no databases and you are applying a new CU, I would expect it to throw errors and maybe even fail. Exchange just isnt expecting that you will have no databases at all.
You can safely delete the monitoring mailboxes and the associated AD accounts. They will be created once you restart the Exchange health service in the remaining database.
When you delete the databases not needed, you may see an error related to health mailboxes:
https://learn.microsoft.com/en-us/exchange/troubleshoot/administration/remove-mailboxdatabase-cannot-remove-health-mailboxes
And yes, I would move the arbitration mailboxes to the database you want to keep.
Get-Mailbox -Arbitration | New-MoveRequest -TargetDatabase <DBYouareKeeping>