Hi,
have a unique scenario and seeing if i can do the work without leveraging a tools based migration.
Here is my scenario
Company A is in a hybrid configuration with Exchange on prem and office 365
Company B was acquired and is fully exchange 2010 on prem
there is already a plan under way to do an AD migration of the user objects. The forest will go away once the consolidation is done
Is there a way where i can do remote mailbox moves from the source envrioment without attaching AAD connect to that envrioment?
I envision a scneario such as the following
1) configure enough of the hybrid envrioment in company b to enable a remote mailbox move to Office 365 (making the routing addresses, migration endpoint, accepted domains etc.)
2) leverage AD migration tools to sync the necessary exchange AD data to the source forest to create the concept of a on prem mailbox in Office 365 (and groups etc.)
3) perform a remote mailbox move of the mailbox data
4) finalize the migration
5) sync the updated mailbox attributes to Company A's forest so that it is seen as a remote mailbox on both sides
6) user's outlook client would get the redirect from on prem to o365 and not require a redownload fo the OST as the mailbox GUID is the same.
it's a very large environment (4000 users, 20TB of data) so i'd like to avoid going tools based if at all possible.
