How to Transition from Exchange 2007 to Exchange 2010

I have listed below some important considerations that might help you in working on that transition plan from Exchange 2007 to Exchange 2010. As you know, Exchange Server 2007 and Exchange Server 2010 are similar in architecture so the transition process is more straightforward.

So, why did I posted this? Well, a good coincidence actually. A colleague from Nepal asked me for a transition plan and it turned out my email to him was very well-documented, detailed and good enough to post it here. :)

The following list or procedure illustrates a typical transition from Exchange Server 2007 to Exchange 2010.

Prerequisites:

• In Active Directory, Run DCDIAG, NETDIAG and check if FSMO roles are functioning perfectly.
• The Active Directory forest and domain has to be running on at least Windows Server 2003 native mode
functionality level.

Note: Ideally, migration/transition of Active Directory to Windows 2008 is much recommended.

• Each site should have at least one Active Directory with the PDC, schema master and the Global Catalog
server roles on at least Windows Server 2008 SP2 version.

Note: It is recommended to have 64-bit type Domain Controllers and Global Catalog Servers for optimal performance preferably Windows Server 2008 x64 SP2 or Windows Server 2008 R2.

• All Exchange Server 2007 servers must have Exchange Service Pack 2 installed.
• The Internet facing Active Directory sites must be the first sites that will be migrated to Exchange Server
2010.

Note: This is the site where the Edge and Hub/CAS roles will be installed and published to the internet.

• Software Prerequisites for the Exchange 2010 Servers.
o Operating system for Exchange 2010 is either Windows Server 2008 SP2 64 bit or Windows Server
2008 R2. o Internet Information Server needs to be installed in the Hub/CAS Server.
o Web Certificates must be installed in the Hub/CAS Server
o Windows Remote Management (WinRM) 2.0
o PowerShell 2.0
o NET Framework 3.5
o Desktop Experience
• Net. TCP Services started and set automatic (via services.msc in Windows OS)
• Disable TCP/IP6 from Registry to avoid conflict if TCP/IP4 is the one used in your network
• Prepare 2007 Office System Converter for desktops/laptops

Precautions:

• Backup Active Directory global Catalog servers, Exchange servers and Servers that interoperate with
Exchange Server, such as gateway systems or replicated directory servers.

Note: If you are using applications (ex. FIM, ILM, MIIS) that replicates with Exchange, it is also a best
practice to turn off any of these replications to other environments during the transition process.

• In-place upgrade to Exchange Server 2010 from Exchange 2007 is not supported
• Servers should be 64-bit.

Sequence of the Transition:

Once you have finished the preparing and working on the prequisites, you have to take the installation order of the Exchange Server 2010 servers into account to minimize the risk:

For Main Site:

• Install Exchange Server 2010 Client Access Server
o Install Prerequisites
o Install CAS Server role
o Transfer OWA, ActiveSync, and Outlook Anywhere traffic to new CAS servers

Note: The Client Access Server can work with an Exchange Server 2007 Mailbox Server as well as an
Exchange Server 2010 Mailbox Server.

• Install Exchange 2010 Hub Transport Server (New Internal and External Connector)
o Install Prerequisites
o Install Hub Transport Server role
o Transfer inbound and outbound mail connector to the new Exchange 2010 Hub Transport Server

Note: Documents all the policies you have in existing Exchange 2007 Hub Transport and apply same in new Exchange 2010 Hub Transport server.

• Install 1st and 2nd Exchange 2010 Mailbox Server
o Install Prerequisites
o Install Mailbox Server role
o Configure DAG
o Create public folder replicas on Exchange 2010 servers using Exchange 2010 Public Folder tool.
o Move Mailboxes using the Move Mailbox Wizard
o Re-home the Offline Address Book (OAB) generation server to Exchange Server 2010.
o Transfer all Public Folder Replicas to Exchange Server 2010 Public folder stores.
o Delete Public and Private Information Stores from Exchange 2007 servers.

Note: After you have installed the Mailbox Server role and established a proper Public Folder
replication between Exchange Server 2007 and Exchange Server 2010, you can start moving
mailboxes to the new Exchange 2010 Mailbox Server. The Public Folder replication needs only be
configured when Public Folders are used in Exchange Server 2007.

• Install Edge Transport Server
o Install Prerequisites
o Install Edge Transport Server role
o Remove Exchange 2007 Edge Transport Subscription

Note: This can be installed at any time, since an Exchange Server 2010 Edge Transport Server can be
subscribed to an Exchange Server 2007 SP2 Hub Transport Server. Use Export and Import option for
all policies applied in previous Edge Transport server.

• Install Exchange 2010 Unified Messaging Server
o Install Prerequisites
o Install Edge Transport Server role

Note: Ideally, having Lync 2010 in-place will make it easier to configure Exchange UM and provide better user experience.

• Uninstall all Exchange 2007 Servers


Once the main site is up and running, then it will be best to start with the implementation of Exchange 2010 in the back up site--if you have a backup site. In terms of installation sequence, it’s not that complex anymore.

Lastly, one really good advantage of transition from Exchange Server 2007 to Exchange Server 2010 is if Outlook clients are at 2007 version (or above)--I’m assuming--the move mailbox process does not result in downtime, making the transition process completely transparent to end users. :)