So, here's the thing about Windows Server 2008: It's been getting rave reviews from everyone I've talked to. We've already migrated much of our infrastructure to it at 3Sharp, and I know several people who have replaced the Vista installations that came on their late-model laptops with Server 2008. However, I haven't yet seen a big surge of enthusiasm toward Server 2008 as a platform for Exchange Server deployments. That's got me thinking about why that might be so.
On one hand, Server 2008 and Exchange Server 2007 would seem to be a natural match. Server 2008 adds several useful features, including the ability to stretch clusters across multiple IP subnets and greatly expanded support for hot-swappable hardware.
On the other hand, this support comes at a price.
First, you can't perform an in-place upgrade from Exchange 2007 running on Windows Server 2003 to Server 2008. That means you essentially have three choices to upgrade your servers:
- build a new server with Server 2008, then move mailboxes from existing servers to the new one;
- move mailboxes from the existing server to a "swing" server, then upgrade the existing server, then move the mailboxes back; or
- back up the mail data from the existing server, then upgrade it to Server 2008, either through a clean install or by removing all the existing components that can't be upgraded, such as Exchange and PowerShell.
None of these options are trivial to implement, and that's clearly part of the problem: Administrators who are already nervous about the prospect of moving to the x64 version of Windows 2003 are generally not in a hurry to move to Server 2008. The no-in-place-upgrade problem will also inhibit casual experimentation with the new combination.
The second limitation of using Server 2008 as an Exchange platform is that some of Server 2008's most intriguing new features aren't usable with Exchange. For example, the new Server Core role, which lets you run many server-based applications without a GUI on the server, doesn't support PowerShell or the .NET Framework—both of which Exchange 2007 requires. So, no Exchange on Server Core. Exchange doesn't make use of Server 2008's read-only domain controllers, so you might not get much value from deploying them in your Exchange environment.
A third strike against Server 2008 for Exchange, whether fair or not, is that many administrators have the firmly held opinion that they won't deploy any Microsoft product until its first service pack is released. Exchange 2007 SP1 is available now, but it will be a while until Server 2008's first service pack is released.
Despite all this, there's one killer feature that I think will drive adoption of Server 2008 for use with Exchange: Hyper-V. Virtualization is becoming an increasingly hot topic in the Exchange world, and Hyper-V promises to provide full support for virtualized Exchange deployments—something that has been in increasing demand as virtualization has become more and more broadly deployed. Look for more on this topic in a future column.