Exchange Mail Routing between domains


  • Dear all,

    I have two single domain forest networks, each with Exchange 2010 in hybrid mode with O365

    The mail flow for each domain is as follows: public MX>firewall>mail filter>exchange 2010>on-prem mailbox OR O365 mailbox

    Lets call the two environments A and B. I would like route all mail from A to B, however in the first phase leave the public mx records as they are and re-route the mail once it hits the exchange servers.

    So external mail for Environment A would hit mx>firewall>mail filter>exchange 2010 (A)>route to exchange 2010 (B)>on-prem Or O365 mailbox

    There would be a policy setup so that some mailboxes would receive an additional email alias for environment A

    In the old days we used routing groups / connectors to route mail between exchange servers, just wondered if there is a better way to do routing?

    Thursday, May 10, 2018 8:45 AM

All replies

  • look at internal relay domains and send connectors that will achieve your goal.

    **Please don't forget to mark as helpful or answer**

    Thursday, May 10, 2018 12:27 PM
  • Hi Java_MCSE,

    Mails choose the MX record by their domain. If mailboxes are in environment B, they will use MX B and be routed to environment B, they will not choose environment A. 

    By the way, Mailboxes on environment A don’t have a mailbox on environment B, if you redirect all mails from environment A to B, where those mails go?


    Kyle Xu

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    Monday, May 14, 2018 11:22 AM