Migration from Zimbra to o365

Dias DT 21 Reputation points
2021-03-31T12:41:52.273+00:00

Hi Sirs,

We have one mail server zimbra, and want to migrate some users from Zimbra to o365.
We could migrate for example 10 users from zimbra to o365 (by imap migration, csv etc) assigned licenses.
As far as I know in order they (migrated users) could work on o365 completely we have configure dns settings on domain which we selected as default EAC. If we add the records which are required, the zimbra wouldn't start work properly. But we want to keep both servers as online. What should we do in further in order both servers could send email to each other (send\receive from\to internal\external emails)
If sender (doesn't matter if he external or user zimbra) send an email to the user o365, email anyway comes to zimbra server.
Hope I could explain the situation.

Thank you!

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Accepted answer
  1. Joyce Shen - MSFT 16,646 Reputation points
    2021-04-01T02:11:05.477+00:00

    Hi @Dias DT

    That's the expected behavior you described above. If you point the MX record to O365, this helps ensure that email is delivered to your Microsoft 365 or Office 365 mailboxes. Moving the MX record will also let you turn off your old email system when you are ready.

    So if you want to keep both mail servers and want them able to send mails to each other, keep the MX record to your source server and for the users migrated to o365 already, sending mails to them by using .onmicrosoft.com addresses

    For more information: Why do I have an "onmicrosoft.com" domain?

    If an Answer is helpful, please click "Accept Answer" and upvote it.

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  1. Emmanuel Dreux 11 Reputation points
    2023-03-29T14:41:01.95+00:00
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