My company has two domains, I want to merge them?

Posted on 2011-10-20
Last Modified: 2012-08-13
Ok, a company I manage IT for has 2 domains, all Windows shop, in two separate locations. One is in Washington state, where all the users are. In the office there are 1 domain controller for user's desktop logins and Active Directory, 1 backup, several in house application servers, file servers, and nightly backups run to a file server.

In CA, in a data center, resides the other domain, which the user's Exchange and OWA accounts run off of. Also has a main domain controller and a backup. This domain location has the web server in a DMZ, and also a Citrix connection from WA to a server here in CA.

The two domain names are different. How would I go about merging them? I don't know where to begin. The usernames are different for the same users on the domains. What would you suggest?

Some things to consider are many of the user's email/Exchange account names are different from their desktop login. I'd like to keep it this way after the domain merger. Both domains have different ISP's and firewalls of course.

On a side note, I also plan to upgrade the domain controllers to Windows Server 2008 from 2003. Only the CA side will need to purchase a physical server capable enough to run 2008.
Question by:stadmin
    LVL 13

    Expert Comment

    I would take the opportunity to look at hosted exchange as this is the only part in the datacenter... If that's not possible.

    1 setup vpn between the sites.
    build up the new hardware and install exchange in ca
    Create mailboxes on the new exchange Change over the receiving server to let email flow in to the new server.

    Export all the mailboxes to pst using exmerge or powershell.
    Import the mail to the new system using same tools.

    As the users already exist in both domains you can't port the over. You have to extend your main domain to also host exchange and migrate the data over.  
    LVL 11

    Accepted Solution

    I don't normally refer to blogs as references but this one seems to be exactly what you are looking for.
    LVL 13

    Expert Comment

    High level for you to start planning/researching:

    Create a Two-way Forest Trust between the domains
    Choose which domain shall become the de facto or create a new domain
    Use ADMT tool to migrate the objects from the deprecated domain(s)
    Use Powershell and/or Exmerge to migrate the mailboxes
    Update recipient policies in Exchange
    Update external domain MX records
    LVL 1

    Author Comment

    It appears Active Directory Migration Tool will be what I need. What can you guys tell me about how Exchange will be merged into the one Directory? It is currently on the domain that will be moved over to the other one. Will I be able to run redundancy, meaning having the primary domain controller in WA and the secondary in CA, and the Exchange server in CA?
    LVL 13

    Expert Comment

    Basically exchange doesn't have to be in any location it should be close to the biggest user group. also for redundancy if possible I would create a secondary exchange in another location especially if you are going to upgrade to ex2010 .

    First start with how you want to end up and then plan migration..

    IE you want to end up with 1 domain 2008 with exchange 2010 both high available.
    2 sites x users per site
    X member servers

    Needed is at least
    1 domain controller per site (optionally 1 extra in the main exchange site for global catalog etc )
    1 exchange server per site in dag together basically to let the mailstores be redundant
    At least 1 cas role server and at least 1 hub transport  server (depending on number of users some of these  
    Roles can be combined.

    oNce you have this you can check the existing hardware.

    Write Comment

    Please enter a first name

    Please enter a last name

    We will never share this with anyone.

    Featured Post

    Why do Marketing keep bothering you?

    Is your marketing department constantly asking for new email signature updates? Are they requesting a different design for every department? Do they need yet another banner added? Don’t let it get you down! There is an easy way to manage all of these requests...

    Set up iPhone and iPad email signatures to always send in high-quality HTML with this step-by step guide.
    ADCs have gained traction within the last decade, largely due to increased demand for legacy load balancing appliances to handle more advanced application delivery requirements and improve application performance.
    In this video we show how to create a Contact in Exchange 2013. We show this process by using the Exchange Admin Center. Log into Exchange Admin Center.: First we need to log into the Exchange Admin Center. Navigate to the Recipients >> Contact ta…
    In this Micro Video tutorial you will learn the basics about Database Availability Groups and How to configure one using a live Exchange Server Environment. The video tutorial explains the basics of the Exchange server Database Availability grou…

    779 members asked questions and received personalized solutions in the past 7 days.

    Join the community of 500,000 technology professionals and ask your questions.

    Join & Ask a Question

    Need Help in Real-Time?

    Connect with top rated Experts

    11 Experts available now in Live!

    Get 1:1 Help Now