Avoiding Failures and Disruptions During Server Upgrades

Commonly overlooked server hardware and operating system service packs can cause unrecoverable failures and lengthy downtime when upgrading servers. Understanding the hardware being used for upgrading and installing the proper service packs for compatibility will help you perform the migration and prepare for any physical failures or migration tasks that need to be repeated.

Planning for Failed Hardware

Whether upgrading existing server hardware to Windows Server 2003 or installing new server hardware, failures of physical hardware components can affect a migration timeline and schedule.

With a detailed hardware inventory, you can plan and purchase spare components such as hard drives , memory, and RAID controllers to ease recovery in case of a hardware failure. This is often a good practice especially when network availability is a priority. This can also be beneficial when upgrades are being performed on server hardware that has been in production for any length of time.

Windows NT Upgrade Paths and Service Packs

When preparing a network for upgrade, you must plan to upgrade all Windows NT Server operating systems, taking into account the operating system version. With many organizations supporting various versions of the Windows NT 4.0 Server operating system, you must determine whether the existing installations of Windows NT 4.0 meet the minimum Microsoft requirements for upgrading as well as minimum Service Pack revisions required for an upgrade to Windows Server 2003.

Windows NT Upgrade Paths

Not all Windows NT 4.0 server operating system platforms can be upgraded to just any Windows 2003 Server family platform. To understand the different upgrade paths and options available, look at Table 14.2. This will assist you in planning the best approach to implement your design and design needs.

Table 14.2. Microsoft Supported Upgrade Paths

	Standard Edition	Enterprise Edition	Datacenter Edition	Web Edition
Windows NT 4.0 Server	X	X
Windows NT 4.0 Terminal Server Edition	X	X
Windows NT 4.0 Enterprise Edition		X

Meeting Windows NT Service Pack Requirements

The Windows NT 4.0 Server upgrade paths are only supported by Windows NT 4.0 Service Pack 5 or later. It is always best to install the latest service pack and allow time to evaluate the service pack installation by reviewing server logs and server performance before upgrading.

Conduct a detailed review of all servers being upgraded in the migration plan. Determine any required service pack installations needed and schedule a service pack upgrade for any existing Windows NT 4.0 servers not meeting the minimum requirements. As a good practice, allow these systems to run long enough to evaluate their performance and stability to ensure that they are not experiencing any issues prior to performing any upgrades to Windows Server 2003.

Installing a Clean Copy of Windows Server 2003

Whenever upgrading existing Windows NT Servers, Microsoft recommends installing a clean copy of Windows Server 2003 as a best practice whenever possible.

Further information about service packs requirements and server upgrade paths can be found at http://www.microsoft.com/windowsserver2003/evaluation/whyupgrade/supportedpaths.mspx.