Forum Discussion

Remo Pistor's avatar
Remo Pistor
Copper Contributor
Jan 23, 2019
Solved

Merge/move 2 AD's and 1 Office 365 tenant to new AD

I've stepped into a mess and need to figure a way out. Our current situation: Two locations with separate AD's:  location one - location1.company.com location two - location2.local One Office 3...
hybrid
migration
office 365
On-Premises
  • ChrisHoardMVP's avatar
    ChrisHoardMVP
    Jan 23, 2019

    Hi,

    This is based purely on what you have outlined above and it's a personal opinion - others will have their own.

    1.) Cut AAD Connect on Location two so the AD and 365 tenant is separate.
    2.) Set all 365 users UPN to @company.com, mail addresses remain the same
    3.) Build new Forest corp.company.com
    4.) Consolidate the AD's into the new forest
    5.) In AD all users to have a UPN Suffix of @company.com, or UPN of @company.com
    6.) Install Member Server/Azure AD Connect
    7.) Ensure the AD objects have the right mail address
    8.) Soft match the users from new Forest to 365

    That's a general overview. It's probably best to take a step back and disentangle what's there first even if it means having cloud users and separate credentials for a period of time.

    Hope that helps

    Best, Chris

ChrisHoardMVP's avatar
ChrisHoardMVP
MVP
Jan 23, 2019

Hi,

This is based purely on what you have outlined above and it's a personal opinion - others will have their own.

1.) Cut AAD Connect on Location two so the AD and 365 tenant is separate.
2.) Set all 365 users UPN to @company.com, mail addresses remain the same
3.) Build new Forest corp.company.com
4.) Consolidate the AD's into the new forest
5.) In AD all users to have a UPN Suffix of @company.com, or UPN of @company.com
6.) Install Member Server/Azure AD Connect
7.) Ensure the AD objects have the right mail address
8.) Soft match the users from new Forest to 365

That's a general overview. It's probably best to take a step back and disentangle what's there first even if it means having cloud users and separate credentials for a period of time.

Hope that helps

Best, Chris

  • Remo Pistor's avatar
    Remo Pistor
    Copper Contributor
    Jan 23, 2019

    ChrisHoardMVP 

    Oh yes, I like this idea. I knew I would probably have to take a step or two backwards, but I never considered disconnecting O365.

    So basically to super simplify it,

    • disconnect the sync,
    • create new forest
    • join domains to new forest
    • reconnect to original tenant

    What if before reconnecting to O365 I wanting to merge old AD's to forest domain? Would you recommend ADMT?

     

    Thanks,

    Remo

    • adam deltinger's avatar
      adam deltinger
      MVP
      Jan 23, 2019
      Yes! Admt will do! It depends how many objects and the structure of the current ad’s too! Sometimes its just more ideal to create from scratch- having a clean AD! Too many ads out there are a mess! But of course this might not be feasible:)
      • Remo Pistor's avatar
        Remo Pistor
        Copper Contributor
        Jan 23, 2019
        AD's are not overly complicated or large. Probably less than 500 objects.
    • ChrisHoardMVP's avatar
      ChrisHoardMVP
      MVP
      Jan 23, 2019
      Correct, that's how I would approach it to keep it as simple as possible. I would 100% merge the old AD's before reconnecting so you have 1 365 tenant, 1 AD. It's very simple after that point.

      ADMT is usually the tool that most organisation use to consolidate AD so would be recommended.

      Best, Chris
      • Remo Pistor's avatar
        Remo Pistor
        Copper Contributor
        Jan 23, 2019
        Awesome. Thanks for the guidance!