Migrating SBS AD to an Server 2012 AD with diffrent domains

Question

The situation, I have a SBS 2008 server which also is the DC for the domain.
The name of the domain is Example: DomainA.
The other server is a W2012 server, which will be replacing the SBS server.
The name of this domain is: Example: DomainB so the names are not the same.

Now I want to start migrating the AD from the SBS server tot the W2012 server.
What would be the smartest thing to do? Also another note for this, ADMT does not work.
How can I accomplish this?

Solution 1

I would advise (temporarily) setting up your new domain on Server 2008 R2, as I've done with my current employer's new forests.

1. Set up your new forest on a (temporary) Server 2008 R2 domain controller.
2. Join your Server 2012 server to the new domain, and promote as a domain controller.
3. Transfer all FSMO roles to the 2012 Domain Controller.
4. "Migrate" SBS 2008 to a proper domain (that supports trusts), based on Server 2008 R2, or set up a secondary DC in the SBS domain to allow trusts natively on the SBS domain.
   • If you're having difficulty, there are a couple unofficial guides to "migrating" SBS 2008 to Server 2008 R2, here and here.
5. Establish your trust between the two forests.
6. Migrate using ADMT.
7. Replace/upgrade/demote Server 2008 R2 Domain Controller.
8. Raise Forest and Domain Functional Levels to 2012.

Basically, since you should always have at least two domain controllers per domain, it's not a big deal to make one of them a Server 2008 R2 server, to provide compatibility with ADMT 3.2, perform your migration, and then upgrade or replace the Server 2008 R2 domain controller to 2012. Just one extra step so you can use ADMT to make the migration process a lot easier.

Solution 2

If you want to stay on the supported path:

1. migrate to Server 2012 Essentials
2. transition to Server 2012 standard
3. set up trusts to the destination domain
4. set up Server 2008 R2 DCs in source and destination domains (unless a newer version of ADMT supports Server 2012)
5. Use the 2008 R2 servers to migrate your domain using ADMT

You might consider taking a shortcut and simply join additional Server Standard DCs to your domain, transfer the roles and demote / remove the SBS to condense three steps. See this post on how this might look in detail. Also, as far as I remember, you could set up trusts with an SBS 2008 domain as long as you did so using secondary domain controllers (i.e. not the SBS itself). With SBS 2011, trusts created in this way have been automatically removed by the SBS DC, while SBS 2008 has just prevented you from creating the trusts, leaving them intact once they were in place.

Comments

[MichelZ]

Can you please explain why ADMT does not work?

[Innominatum]

It is not supported by microsoft. link

[MichelZ]

While technically not supported, Microsoft still seems to use it for scenarios like that: blogs.technet.com/b/sbs/archive/2009/05/01/…

[the-wabbit]

Note that ADMT probably would work as soon as you manage to set up a trust between the source and the destination domains.

[Innominatum]

Tried to get ADMT working, won't work

[HopelessN00b]

ADMT doesn't work with a purely 2012 domain - needs a Server 2008 R2 target. ... which is why all my shiny new forests are still at a 2008 R2 FL - to accommodate a 2008 R2 DC in each new forest, serving as our ADMT target.

[Rex]

+1 But this is the hard way. You can actually lower the forest/domain functional level to 2008 R2 in a domain with only 2012/2012R2 domain controllers which should allow ADMT to work without standing up an actual 2008 R2 server. support.microsoft.com/kb/2753560

[Rex]

Also, per the last blog update on the subject, a new version of ADMT should be out "soon". Blog states Q1 2014 which is already passed.. blogs.technet.com/b/askds/archive/2013/12/13/…

[HopelessN00b]

@Rex No, that doesn't work. (I've tried.) The ADMT installer needs a 2008 R2 OS to install onto - check the resolution from the article you linked. When you migrate to a Windows Server 2012 domain, install ADMT 3.2 on a Windows Server 2008 R2 server that can operate as the migration computer. You have to have a Windows Server 2008 R2 domain controller in the target environment. You have to have a Windows Server 2008 R2 domain controller in the target environment. So at least until they roll out that new ADMT version they've promised, having a 2008 R2 DC is the only way to use ADMT.

[the-wabbit]

You... you stole my link! Give it back!

[HopelessN00b]

@syneticon-dj Heh, sorry, I didn't see it in there. No theft intended... by all means, grab it back if I want. I have it here for your convenience. =D

[the-wabbit]

Ah, thanks. I see you've followed the laundry symbols' instructions - it still is as good as new!