A reader emailed me to ask how they can go about upgrading their current environment without breaking Exchange.
They are currently running Exchange Server 2000 with Windows Server 2000 domain controllers, and wish to transition to Exchange Server 2007 and Windows Server 2008 domain controllers.
Although you can transition from Exchange 2000 to 2007 the problem in this case is the move from Windows Server 2000 to Windows Server 2008. Exchange 2000 will not work with Windows Server 2008 domain controllers, and Exchange 2007 will not work with Windows Server 2000 domain controllers.
Exchange 2000 Server Service Pack 3 and all previous versions of Microsoft Exchange are not for use with Windows Server 2008 directory servers. The following restrictions apply with respect to Exchange 2000 Server Service Pack 3:
- Exchange 2000 Server Service Pack 3 can exist in an Active Directory forest that contains Windows Server 2008 directory servers, but Windows Server 2008 directory servers should not be installed in Active Directory Sites that contain Exchange 2000 Server.
- If Windows Server 2008 directory servers must be deployed Active Directory Sites that contain Exchange 2000 Server you must first hard-code directory service access (DSAccess) on the Exchange 2000 Server servers in the site to point to directory servers running Windows Server 2003 or Windows 2000 Server.
In other words, at some point the reader will need to install a Windows Server 2003 domain controller to make the whole transition possible.
My recommendation is to use these general steps:
- Install a Windows Server 2003 domain controller into the site(s) that will be hosting Exchange Server 2007, so that the environment pre-requisites for Exchange 2007 are met (ie, Windows Server 2003 SP1 DC/GC in the AD Site hosting Exchange 2007, plus the Schema Master must be Windows Server 2003 SP1)
- Transition from Exchange Server 2000 to Exchange Server 2007
- Introduce Windows Server 2008 domain controllers into the environment where required (upgrading the temporary Windows Server 2003 DC to 2008 is supported too)