Question : Exchange Servers across Multiple Domains and One GAL

It's been a long time since I've setup a configuration like this:

aaa.mycompany.com
bbb.mycompany.com
ccc.mycompany.com

Each One has it's own exchange server.  Each is a 2003 Enterprise Server, with Exchange 2003.

I'd like to be able to either have only One GAL for the 3, or sync the GALs between them.  Is this possible without 3rd party software?  How can I achieve this?

Back in my day of being a network admin in the US Military, we had several different domains (like above) and exchange servers (some domains had more than 1), but there was the 1 GAL.  This is the type of infrastructure I'd like to achieve.

Answer : Exchange Servers across Multiple Domains and One GAL

Hi usmcguy,

If all three domains are in the same AD forest, this will be very simple.  There can only be one Exchange organisation per forest, and the GAL is shared between all Exchange servers in the organisation.

If each domain is in a separate forest, you will need to use a tolol like the Identity Integration Feature Pack (IIFP) to synchronise the GAL:
IIFP Download: http://www.microsoft.com/downloads/details.aspx?FamilyID=d9143610-c04d-41c4-b7ea-6f56819769d5&displaylang=en
IIFP Guide: http://www.msexchange.org/tutorials/GAL-Sync-Identity-Integration-Feature-Pack-IIFP.html

Cheers,

D