One of a system administrator's many responsibilities is to ensure that newly published system patches, including full service packs, work as intended -- and if they don't, to find out how they fail to interact with an existing setup. So what's the best way to test such patches in a controlled environment?

The generic recommendation is to reserve a standalone Windows machine to be used as a guinea pig and to set it up to resemble a standard workstation as closely as possible. However, given how tight IT budgets are nowadays and the fact that some shops simply don't have the physical space for a test machine, this isn't always a practical suggestion.

One alternative is virtual computing. Programs like Microsoft Virtual PC and VMware make it possible to emulate a PC's entire operation (hard drive, operating system, network, etc.) on another PC's desktop. With this type of tool, an administrator can create a virtual test machine with the same software loaded onto the average user's computer. It also makes testing substantially easier: If the administrator wants to back up the test system before determining how a particular patch behaves, all he has to do is copy a file instead of re-image an entire computer.

Often, the emulated machine can run at approximately 75% of its host's speed, and speed isn't typically a primary concern when testing for compatibility and proper patch behavior.

Note that if you use a specific hardware configuration that cannot be emulated in a Virtual PC (for instance, a biometric identification device), this type of tool may be less useful, depending on which one you use. VMware supports the near-transparent emulation of most USB hardware, while Virtual PC does not.

About the author: Serdar Yegulalp offers his expertise in Windows NT, Windows 2000, Windows 2003 and Windows XP as publisher of the Windows Power Users Newsletter.

More information from

  • Tip: Get the top five security enhancements in Windows Server 2003 SP1
  • Topic: Research technical tips and expert advice on patch maintenance
  • Tip: Find out what not to do when patching

  • This was first published in May 2005

    There are Comments. Add yours.

    TIP: Want to include a code block in your comment? Use <pre> or <code> tags around the desired text. Ex: <code>insert code</code>

    REGISTER or login:

    Forgot Password?
    By submitting you agree to receive email from TechTarget and its partners. If you reside outside of the United States, you consent to having your personal data transferred to and processed in the United States. Privacy
    Sort by: OldestNewest

    Forgot Password?

    No problem! Submit your e-mail address below. We'll send you an email containing your password.

    Your password has been sent to:

    Disclaimer: Our Tips Exchange is a forum for you to share technical advice and expertise with your peers and to learn from other enterprise IT professionals. TechTarget provides the infrastructure to facilitate this sharing of information. However, we cannot guarantee the accuracy or validity of the material submitted. You agree that your use of the Ask The Expert services and your reliance on any questions, answers, information or other materials received through this Web site is at your own risk.