ISA Server installation dos and don'ts

Overlook hot fixes and security packs and installation security can fly out the window, according to Microsoft security expert Joern Wettern. During Microsoft's recent TechEd 2002 conference in New Orleans, Wettern detailed the dos and don'ts to securely install Microsoft's Internet Security and Acceleration (ISA) Server, a full firewall and proxy server.


  • Do think about what the role of ISA Server should be within a domain, said Wettern. "Domain membership is required only for arrays and user-based rules," he said. Perhaps, then you'll just want to install it as a regular member server.


  • Do create a separate domain or forest if you want an array. Keep in mind, however, that will only slightly increase security and will be at a large software and hardware cost. A separate forest can make sense in a perimeter network, or demilitarized zone (DMZ). "It makes sense to have a separate Active Directory forest in a DMZ, but don't make it related to the internal AD forest," said Wettern.


  • Don't forget to disconnect the computer from the Internet. "That sounds so simple," Wettern said, "but you'd be surprised how many people forget."


  • Do install Windows 2000 Server and only the required components. Do figure out what type of server it

Requires Free Membership to View

  • will be. Ask yourself: Will it be a Web server or mail server or something else?


  • Do install the latest service packs and security rollup packages. Wettern recommended HFNetChk or Security Baseline Analyzer to find the needed hot fixes.


  • Do disable any unnecessary services. What is unnecessary depends on the specific network environment and how the server is configured, said Wettern.


  • Do remove bindings. Unbind all services from external interfaces. Keep only TCP/IP enabled.


  • Do install only the required components and review the local address table (LAT) before continuing. The LAT records which subnets or ranges are on the internal network. This is most important because the LAT can contain the wrong IP addresses and create a security risk, said Wettern.


  • Do install service pack one (SP1) and any applicable hot fixes.


  • Don't forget that "after ISA Server is installed, it blocks all traffic until you allow it," Wettern said.


  • In terms of additional security, don't forget the network infrastructure. Do use a filtering router as your first line of defense and to defeat DoS attacks, said Wettern.


  • Do use third party add-ins for virus protection and intrusion detection.

This was first published in May 2002

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.