Preview: Windows Server 2008 R2

Computerworld - Receiving slightly less attention than its client brother, Windows Server 2008 R2 -- also known as Windows 7 Server -- made its prerelease debut a couple of weeks ago. But with this new incremental release, there are quite a few changes under the hood that may make this something you should watch. In this piece, I'll look at some general facts about the release and then drill into a few key improvements and new features.

64-bit only

Windows Server 2008 R2 will be the first mainstream Windows Server release to be 64-bit only, meaning that older servers that don't support one of the families of 64-bit processor extensions won't be able to be upgraded. They will, however, be able to run Windows Server 2008, and some of the enhancements in R2 will work fine in environments with servers running plain-vanilla Windows Server 2008 as well. This release also marks the second time the client release (in this case, Windows 7) and the server release of the Windows product have been developed jointly, resulting in tighter integration, better compatibility and an extensive amount of testing.

Kernel-level changes

One of the big concerns around Windows Server 2008 R2 may be the changes that were made to the operating system kernel that will allow Windows to support up to 256 processors. Microsoft Corp. expects that compatibility with Windows Server 2008 will be nearly identical to the level of compatibility that existed between Windows Server 2003 and Windows Server 2003 R2. But because these low-level changes were made, Microsoft can no longer guarantee 100% application compatibility in this release, as it could between Windows Server 2003 and Windows Server 2003 R2. When making deployment plans, be sure to account for this testing time.

Key feature highlights

Here are some of the key nice bits included in Windows Server 2008 R2 at the M3 milestone, which was the build given to attendees of the Professional Developers Conference just a couple of weeks ago:

• Live migration: This is, of course, the Microsoft response to VMware Inc.'s popular VMotion technology that allows you to move a virtual machine from one physical host to another with no downtime -- a seamless transition from the perspective of your users. While the existing release of Hyper-V supports quick migration, there were a few seconds of downtime associated with the move, and that has been removed. This is what many users have been waiting for before settling on Hyper-V for their virtualization solution, and now Hyper-V offers feature parity with VMware's enterprise solutions in many scenarios.
• Hyper-V 2.0: Hyper-V's next release includes several improvements, including support for up to 32 logical processors on the host computer and support for adding and removing virtual hard disks (VHD) to a running virtual machine without needing to reboot the operating system on that VM. It also has dynamically allocated memory without any interruption of service and support for booting for a VHD file so that VHDs can work on both physical and virtual hardware.
• Remote Desktop Services: Originally Terminal Services, the Remote Desktop Services (RDS) umbrella includes solutions for the new virtualized desktop infrastructure, or VDI. VDI allows Windows Vista and eventually Windows 7 to be deployed to centrally managed virtual machines, which in turn lets employees and contractors work in a consistent, managed environment from any location. According to Microsoft, "key benefits of Microsoft centralized desktop strategy include better enablement of such flexible work scenarios such as work from home and hot-desking, increased data security and compliance, as well as easy and efficient management of the desktop OS and applications." Hot-desking is when you have a group of cubicles or desks that exist but aren't permanently assigned to one specific employee -- you just come in and take whatever cubicle is open each day. RDS also includes traditional Terminal Services features such as RDP and presentation virtualization technologies. There are also enhancements to the RDP experience, like better audio streaming, full multimonitor support and an improved multimedia (including video) experience.
• Active Directory Domain Services (AD DS) enhancements: There is a new AD DS management console which features tight PowerShell integration, as well as an AD Recycle Bin that allows recovery of previously deleted objects. You can now join machines to a Windows domain offline, which is useful for branch offices and other connectivity challenged environments. There are also enhancements to Active Directory Federation Services (AD FS), including a feature called "authentication assurance" that I have been unable to test because I haven't had a chance to set up all the equipment I need for it.
• DirectAccess: As I wrote in my IT pro-oriented piece on Windows 7, DirectAccess promises to be end users' favorite feature. DirectAccess allows you to do everything you'd normally do over a virtual private network -- get access to your corporate network, file shares and intranet; perform seamless authentication with company resources; and so on -- without actually having to create the VPN tunnel. You need IPv6 and IPsec, as well as a 6-to-4 router, but those seem to be small prices to pay for an "always managed" infrastructure.
• IIS and Managed Code on Server Core: One of the bigger complaints about the Server Core installation option was that it did not support managed code and the .Net Framework. This has been rectified in the R2 release, allowing for full support for ASP.Net Web applications in addition to PHP and traditional Active Server Pages. You can now also use richer management tools on remote machines, such as your administrative desktop, since .Net is supported on Server Core.

Jonathan Hassell is an author, consultant and speaker on a variety of IT topics. His published works include RADIUS, Hardening Windows, Using Windows Small Business Server 2003 and Learning Windows Server 2003. His work appears regularly in such periodicals as Windows IT Pro magazine, PC Pro and TechNet Magazine. He also speaks worldwide on topics ranging from networking and security to Windows administration. He is currently an editor at Apress Inc., a publishing company specializing in books for programmers and IT professionals.

Read more about NOSes and Server Software in Computerworld's NOSes and Server Software Topic Center.