Exchange 2003 will prove to be a compelling upgrade for many organizations that are currently running Windows 2000 with Exchange 2000 to support their messaging infrastructures. However, many of these same organizations will be loath to migrate to Windows Server 2003 until it has at least one service pack under its belt. Nevertheless, some of them may want to migrate to Exchange 2003 before they have Windows Server 2003. For these companies, Exchange 2003 can run on Windows 2000 Server but with reduced functionality.

In this Daily Drill Down, I’ll examine the pros and cons of running Exchange 2003 on Windows 2000 and provide details on how to carry out an installation.

Testing environment

For all the examples in this article, I’ll be using Windows 2000 SP3 and Exchange Server 2003 beta 2.

The price of running Exchange 2003 on Windows 2000
Exchange 2003 is designed to integrate with Windows Server 2003. The price that you’ll pay for installing Exchange 2003 on Windows 2000 is the loss of a number of key benefits to moving to Exchange 2003 in the first place. These losses include:

  • RPC over HTTP: RPC over HTTP is not a function of Exchange Server but is instead included with IIS 6 running under Windows Server 2003. RPC over HTTP allows an Outlook 11 client to connect directly to the Exchange information store from outside the corporate firewall without the need for a VPN connection. IIS 5 under Windows 2000 does not support this feature for Exchange.
  • Online backups: Users running Exchange 2003 under Windows Server 2003 will be able to take advantage of online snapshots of the information store by utilizing the Volume Shadow Copy service. This service allows for an instantaneous backup and restore of the information store while still online. This removes a primary availability issue from previous versions of Exchange by keeping the information store available constantly and allowing for on-the-fly backups. Windows 2000 does not support the Volume Shadow Copy service.

The benefits
Probably the primary benefit of installing Exchange 2003 onto a Windows 2000 server (rather than Windows Server 2003) is that the impact of introducing a single new service (Exchange 2003) to your infrastructure will be much less than introducing more than one (Exchange 2003 plus Windows Server 2003). Furthermore, if you don’t plan to install Exchange 2003 on new hardware, but would rather upgrade your existing Exchange 2000 installation, you can simply do an in-place upgrade while still running Windows 2000.

Keep in mind that Exchange 2000 will not run under Windows Server 2003. So, if you want to do an in-place upgrade from Exchange 2000 to Exchange 2003, you’ll need to upgrade to Exchange 2003 on Windows 2000 first; then you can later upgrade Windows 2000 to Windows Server 2003.

System requirements
Running Exchange 2003 on Windows 2000 has some system requirements that must be met before you attempt the installation. First, Service Pack 3 for Windows 2000 must be installed on the Exchange server, as well as any global catalogs or domain controllers that Exchange will use. Second, there are software requirements, including the SMTP and NNTP components from IIS, both of which must be installed on the Exchange server. If you’re already running Exchange 2000 on the system, these software components will already be installed. Before upgrading an Exchange 2000 server, be aware that Exchange 2003 removes certain functionality from the product.

Testing environment
I’ll install two Exchange 2003 systems for this article. The first one is a new installation onto a Windows 2000 SP3 system, while the second is an upgrade of an Exchange 2000 SP3 system. Both servers are in separate domains and have DNS, Active Directory, and Global Catalog servers available. 

Demo 1: New installation of Exchange 2003 on Windows 2000
A new installation of Exchange 2003 on a Windows 2000 server will likely be fairly uncommon since Windows Server 2003 is shipping well before Exchange 2003, and organizations that add a new Exchange 2003 server are recommended to simply install it under Windows Server 2003. However, some companies are much more wary about new operating system environments and will choose to deploy Exchange 2003 on Windows 2000.

Before you begin the installation, you need to make sure that the Windows 2000 server you choose for installation meets the requirements I explained earlier. Furthermore, make sure that your DNS servers have the appropriate records for your new mail server. Since I’m installing this on a demonstration server in my lab, it will be running on Windows 2000 SP3 with SMTP and NNTP enabled. The server is also an Active Directory domain controller and runs DNS services.

To begin, put the Exchange Server 2003 CD into the CD drive, which should automatically display the Exchange installation menu (see Figure A). From the menu, choose Exchange Server Setup to start the installation. If you have Autorun disabled on your CD drive, you can start the installer by running setup.hta from the root of the Exchange 2003 CD.

Figure A
The Exchange Server menu comes up when you insert the CD ROM.

For this example installation, I’ll install Exchange 2003 as well as the System Management Tools onto the C: drive of my lab server, as shown in Figure B.

Figure B
This is a default Exchange Server 2003 installation.

Since I don’t have an Exchange organization yet, I need to create a new one (see Figure C). In this case, I’ll use the name E2K3 (see Figure D). If I were running Exchange 5.5, I could also join this Exchange 2003 server to that domain in order to migrate resources.

Figure C
Create a new Exchange organization if you don’t have one yet.

Figure D
The organization name for this example is E2K3.

After these steps, you’re asked to agree to the terms and conditions of the product and are provided with a summary of the selections made. Then, the Exchange 2003 installation will begin.

Alternative installation option

During this installation, the target domain’s schema is extended to support the additional attributes required by Exchange. If you’d prefer to install Exchange in small bites rather than all at once, you can install these extensions before installing the entire product by running setup.exe from the \setup\i386 folder using the /forestprep and /domainprep switches.

The end result of this process is a fully functional Exchange 2003 installation, complete with an SMTP connector to enable mail exchange with the outside world. As you can see in Figure E, the combination of Exchange 2003 and Outlook 11 (2003) also sport a new look.

Figure E
Outlook 11 shows the contents of a mailbox on the new Exchange server.

Demo 2: In-place upgrade to Exchange 2003
Performing an in-place upgrade of Exchange 2000 to Exchange 2003 on Windows 2000 SP3 is very simple once you address the prerequisites. As with any upgrade, you’ll need to do some preparation before you proceed.

First, make sure that certain Windows 2000 servers are upgraded to Windows 2000 Service Pack 3. These servers include any domain controllers and global catalog servers that Exchange 2003 will use, in addition to the Exchange server itself. Second, make sure that Exchange SP3 or higher is applied to all Exchange 2000 servers that you wish to upgrade. If you don’t perform this step, the Exchange 2003 installer will not run.

Since this demonstration presumes that you’re already running an Exchange 2000 system, your server already has the SMTP and NNTP components installed, communication with the domain established, and DNS configured properly. If your current Exchange 2000 installation is itself an upgrade from Exchange 5.5, then I highly recommend new hardware for the Exchange 2003 installation. While keeping hardware static can provide cost savings, if there are difficulties in the process, the fact that multiple upgrades have been done on the system can ultimately make it much more difficult to track down the cause of problems.

Reduced functionality in Exchange 2003

Before upgrading Exchange 2000 to Exchange 2003, you should be aware that Exchange 2003 is missing some features that are present in Exchange 2000. You must remove the unsupported features—instant messaging, chat, and the key management service (KMS)—from your Exchange 2000 installation before upgrading. These Exchange 2000 features cannot be administered using the System Manager from Exchange 2003, and they cannot be enabled on a per-user basis on a server running Exchange 2003. Unfortunately, the removal of these features is not just the result of running beta code. Microsoft has decided to remove them from the Exchange product and create an additional messaging product that has not yet been announced.

First steps
As I alluded to above, the upgrade from Exchange 2000 to Exchange 2003 happens in pieces. The first step is to upgrade the forest’s Active Directory schema to support the new Exchange 2003 extensions;  the second is to prepare the local domain for the upgrade.

To prepare the forest for the upgrade, execute setup /forestprep from the \setup\i386 directory on the Exchange 2003 CD. This will execute the same installer but will only perform the steps required to prepare the forest for the upgrade, as shown in Figure F.

Figure F
ForestPrep prepares the forest for the Exchange upgrade.

You must prepare the local domain for the new Exchange as well. You accomplish this by executing setup /domainprep from the \setup\i386 folder on the Exchange 2003 CD (see Figure G).

Figure G
DomainPrep prepares the local domain for Exchange 2003.

Perform the upgrade
Once you have Service Pack 3 for Exchange installed and have performed both of the preparation steps, running the installer with no switches defaults to the choice of upgrading your current installation, as shown in Figure H. (Notice that the Action column says “Upgrade.”)

Figure H
Get ready to upgrade Exchange 2000.

This process doesn’t take very long and no reboot is required afterward. When you’re finished, you have an upgraded Exchange 2003 installation. At the end of the process, your installation will include the new version of Outlook Web Access by default. During the installation, ASP.NET support is added to IIS in order for the OWA to work.

The new Outlook Web Access is impressive. It’s fast and it very closely mimics the appearance of the Outlook 11 client (see Figure I), which makes the transition between the two easier for users.

Figure I
Outlook Web Access is much improved over older versions.

Installing Exchange 2003 on Windows 2000 or upgrading an existing Exchange 2000 server can move your organization ahead by providing many of the new features in the messaging infrastructure (such as the new version of Outlook Web Access) without the need to roll out a Windows Server 2003 backbone. However, not all of the new features of Exchange 2003 are accessible using this method, and some reduced functionality of the new product may be too high of a price to pay for some organizations.