Forum Discussion
Will server to server migration work cross-domain/cross-active directory?
Back in 2016, I upgraded a client from Exchange 2008R2 to Exchange 2016. The way I did it was "the textbook way" I built the new Exchange 2016 server on the same network as the 2008R2 server, and mi...
Worth considering: have you looked at dedicated Exchange migration tooling? Given the cross-domain complexity you are dealing with, tools in this space can handle mailbox migrations across different AD forests without requiring you to touch the server infrastructure itself.
From what you describe, you are building a net-new AD and Exchange environment in wonkulatinggronkulator.com while keeping wonkulating.com running in parallel. A migration tool lets you select mailboxes individually and schedule them in batches, which aligns well with your groups-of-10-or-20 approach, and sidesteps the PST export/import fallback entirely.