Exchange 2007 Cross forest, multiple companies

Ok, so I have been searching and have found numerous docs that are close to what I'm looking for, but I either got to a point they didn't work or weren't quite fit.

My issues is in two parts:

1) I need to do a cross forest migration of select mailboxes. Basically, we are getting rid of Exchange servers at the child company level and only going to host the Exchange at the parent company. I have created a new forest and have setup trust relationships with the child company domains. That part is working as my "test" account can log into OWA and look at mail using the domain/user and the password from their actual forest/OU.

Now I need to figure out how to get some, not all, of the mailboxes (again, Exchange 2007 to 2007) from the old servers to the new. I have read article after article about migration, but I'm either no understanding something or I'm looking at the wrong thing.

Couple questions:

1) Does anyone have a clear step by step of migrating cross forest?
2) How do I setup users since they are currently user mailboxes and in the new system they will be linked mailboxes? Do I set them up ahead of time? Will the migration take care of this?


Issue 2:

Once I have all of the mailboxes in the new Exchange, How do I set it up so the GAL doesn't list all the users? Ideally, I would prefer each user to get a list of accounts associated with his/her child company only - or basically, how can the GAL per user only list the other E-mail accounts associated with the individual domain.

Thanks in advance
CompuzAsked:
Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

mario_andresMessaging ArchitedCommented:
Compuz

   Here is a link to a very good article. http://technet.microsoft.com/en-us/library/aa997145(v=exchg.80).aspx

It would be beneficial to setup a very simple lab environment and do some trial migration run and document your process.  I never used the Active Directory Migration tool, but
Here is a link to a quick Video of how to use the tool.  

http://www.youtube.com/watch?v=KHIWlWFf2AM
0

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
CompuzAuthor Commented:
Thanks for the help. The lab enviorment worked well
0
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Exchange

From novice to tech pro — start learning today.