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Victor bassey's avatar
Victor bassey
Copper Contributor
Feb 21, 2018
Solved

Multi Forest Hybrid with ADFS, including one none Microsoft mail system

 

Dear community, I am just about commencing an office 365 ( initially exchange online) migration for a global client with 2 AD/Exchange forests and also 2 subsidiary companies that have their separate AD forest but uses other mail system e.g zymbra and Zoho mail.

 

so we have

 

1. forest a.com - runs exchange 2010 with  60% of staffs in this forest

2. Forest b.com - runs exchange 2013, with 20% of staff

3 Forest c.com - runs non Microsoft mail system, 10% of staffs

4. Forest d.com - runs non Microsoft mail system, 10% of staffs

 

The goal is to move every users in these forests to a single tenant in office 365 and also brand everyone with a new company email address.

 

i am thinking I can achieve this by using a multi hybrid exchange/ AD connect setup. My confusion is do I need to initially consolidate all this users to a single Active Directory domain before migration or I can just set up multi hybrid with each forest.

 

Also if I’m using multi forest hybrid setup, would I be able to move all these users to a new email address for the company whilst still maintaining each individual hybrid/Ad connect on premises syncs.?

 

or better still, please advise on how you will tackle this company scenario instead.

 

thank you

  • Hi Victor,

     

    That scenario you must have Trust between Active Directories and you cannot have the same smtp domain across Exchange.

     

    The best way is to consolidate the Exchange in just one Active Directory and then you can have the smtp domain on that.

     

    You can have Exchange with linked mailboxes to other domains using AAD Connect to sincronize them to Office 365.

10 Replies

  • Hi Victor,

     

    For your scenario the best way is to consolidate with one Exchange Hybrid, because it's only supported 1 Exchange Hybrid per Tenant.

     

    If you do not have experience with this kind of project contact a Partner with experience with this consolidations and migrations.

      • NunoAriasSilva's avatar
        NunoAriasSilva
        MVP

        Hi Victor,

         

        That scenario you must have Trust between Active Directories and you cannot have the same smtp domain across Exchange.

         

        The best way is to consolidate the Exchange in just one Active Directory and then you can have the smtp domain on that.

         

        You can have Exchange with linked mailboxes to other domains using AAD Connect to sincronize them to Office 365.

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