Forum Discussion
Multi Forest Hybrid Exchange - same email address all users
Current setup is 2 forests with 2 exchange servers, 2 domains linked via trust. Both Exchange servers are completely separate.
We have been running AAD sync on one member server (in domain a )that syncs domain users from BOTH forests to our Office 365 Tenant.
Currently the on premise exchange servers each receive mail for their respective domain users, a.com and b.com.
I would like to migrate via minimal exchange hybrid each exchange forest to O365, it seems that I would then need to keep both servers on-premise to manage users etc.
Once each exchange is hybrid and mailboxes have been migrated for all users - how possible/easy at this point would it be to allow all users to use domain a.com email address ( and to have b.com as alias )
Yes, you can ;-)
Minimal hybrid supports multi-forest Exchange hybrid deployments.
https://blogs.technet.microsoft.com/exchange/2016/06/24/hcw-improvement-the-minimal-hybrid-configuration-option/ --> have a look at the comments, Tim from Microsoft answered the question.
Alias: you can send email from an address which is the reply address of your mailbox. You can use address rewriting or similar features to accomplish this.
6 Replies
I'm not sure minimal Hybrid is supported with multi-forest scenarios, best contact support to confirm that. Once you get the mailboxes to O365, you should have no problems assigning aliases from either domain though, as they will be in the same organization.
Hi thanks for mentioning that, hopefully I can get this confirmed.
setting an alias would only allow you to receive to that address? I would want all users to have the same email address for sending/receiving.
Yes, you can ;-)
Minimal hybrid supports multi-forest Exchange hybrid deployments.
https://blogs.technet.microsoft.com/exchange/2016/06/24/hcw-improvement-the-minimal-hybrid-configuration-option/ --> have a look at the comments, Tim from Microsoft answered the question.
Alias: you can send email from an address which is the reply address of your mailbox. You can use address rewriting or similar features to accomplish this.
