• Sidebar: Windows System Resource Manager

Windows Server 2003 boasts a number of technical improvements that make it easier to consolidate servers for various processing roles. The opportunities, benefits, and difficulties of consolidation vary by the role the server performs.

How Windows Server 2003 Aids Consolidation

Windows Server 2003 has features that allow consolidation of servers for several types of functions:

File and print networking. Among the improvements in Windows Server 2003 that facilitate the consolidation of file and print servers, the most notable are improved support for network-attached storage (NAS) and storage area networks (SANs), which allow servers to efficiently access large amounts of data, and the Volume Shadow Copy Service (VSS), which takes snapshots of stored data to speed data backup and restoration. Windows Server 2003 can also handle more print queues, and print queue performance is better than on previous versions.

Web and application servers. The Internet Information Services (IIS) Web server in Windows Server 2003 better isolates processes, starts a Web service only when it receives a request from a client, and can restart separate applications without restarting IIS. These improvements reduce the risk of consolidating multiple Web servers with different Web-based applications onto a single server. For example, online dating service Match.com used Windows Server 2003 to reduce its number of Web servers from more than 100 to fewer than 50.

However, consolidation of different applications onto a single server, called heterogeneous consolidation, can be complicated because the combined applications might interfere with each other. For example, one application may require different parameters for an underlying service than a second application. Thus, significant planning and expertise are required for organizations to gain the benefits of heterogeneous consolidation. For example, if the application has the potential to conflict with other applications, then it is important to host it in its own IIS process.

Messaging. Improvements in storage, processing, and applications allow organizations to reduce the number of servers required for a messaging application, such as Exchange Server. For example, Windows Server 2003 now supports storage of Exchange Server 2003 message databases on NAS devices.

Consolidation of an application currently running on multiple servers, a process called homogeneous consolidation, is simpler than heterogeneous consolidation and therefore is a common starting point for consolidation. For example, Microsoft’s IT group is using consolidation to reduce the number of physical locations where Exchange servers are hosted, leading to a 75% reduction in mailbox servers.

Database servers. The ability to support multiple databases on a single server, such as multi-instance support in SQL 2000 Server, allows organizations to consolidate databases.

Core infrastructure. Improvements to core network services, such as Active Directory (AD), also foster server consolidation. For example, improvements to AD in Windows Server 2003, such as universal group caching, reduce the need for remote servers to process network authentication and authorization.

Feature Packs Support Consolidation

Several feature packs for Windows Server 2003, including Services for Unix, Windows System Resource Manager, and the File Server Migration Toolkit combined with other products, such as OS virtualization software, make consolidation more feasible.

Services for Unix. Although Microsoft promotes Services for Unix primarily as a tool to migrate Unix applications to Windows, it can be used to allow Unix applications to run on Windows servers. This enables organizations to eliminate or reduce the number of Unix servers without losing the applications that ran on them.

Windows System Resource Manager. The Windows System Resource Manager (WSRM) is a feature pack for Windows Server 2003 Enterprise and Datacenter Editions that allows administrators to manage processor or memory resources by process or user. This tool plays two roles in server consolidation: helping an organization determine a resource profile for an application (the amount of resources used by an executing application) and ensuring that an application does not steal resources from other applications running on the same server. (For more information, see the sidebar "Windows System Resource Manager".)

Additionally, organizations can use the resource utilization data from WSRM for a chargeback system to ensure that users and business departments pay for the resources their applications consume.

File Server Migration Toolkit. This toolkit, released in Apr. 2004, helps administrators migrate files, folders, and security settings on Windows NT and Windows 2000 Servers to servers running Windows Server 2003 or Windows Storage Server 2003. For example, the tools help an administrator use the Distributed File System (DFS) while maintaining the original universal naming convention (UNC) path of the files after they are moved to the new servers.

OS virtualization software. OS virtualization software, which can emulate multiple guest OSs on a host OS such as Windows Server 2003, enables organizations to run legacy applications from diverse platforms on consolidated servers. For example, a virtual server can be used to create a virtual Windows NT or OS/2 server on Windows Server 2003. In the future, servers could run virtualization software to provide isolation between applications, preventing conflicts that might arise in cases of heterogeneous consolidation. Microsoft is not yet shipping its Virtual Server 2005 (a release candidate was provided to beta testers in June 2005, with final release expected before the end of 2005), but many customers are using virtualization provided by products such as EMC’s VMWare.