Migrating a child Active Directory into a parent domain
Users need to keep their child domain logins while accessing parent systems, but split email environments break directory visibility. Because Exchange Online does not know about them, remote mailboxes cannot see on-prem contacts. This stops administrators from recreating distribution groups in the cloud, since on-prem users still need to email those groups.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
- 1Creating on-premises contacts with matching SMTP addresses for remote users
- 2Syncing contacts to the cloud directory with proper routing addresses
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
“How would we go about migrating the child co AD (users/workstations) into the parent co so that they could continue to login with the child co domain and gain access into the parent co systems?”source ↗
“A onprem Mailbox can see all the contacts and regular members while a remote mailbox from domain 1 can only see the normal mailboxes and not the onprem contacts I created.”source ↗
“Unfortunately I cannot recreate the distribution group in exchange online since also people from onprem exchange needs to mail to the group.”source ↗
“contacts won't show up for remote mailboxes because exchange online doesn't know about them.”source ↗
Where this came up
People with this problem also raised
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