Introduction

As with any piece of computer software, many potential problems with ISA Server can be prevented and time spent troubleshooting thus avoided by careful deployment planning and attention to details during installation and configuration. A classic truism says that it's easier to get it right the first time than to go back and fix it later, and this is especially true when it comes to software. One incorrect setting made inadvertently because you were in a hurry or because you didn't understand how the setting works can result in hours or days of effort later as you search for the cause of the resulting problems.

Some network administrators enjoy the challenge of the hunt. Troubleshooting can be fun, especially when you can do it at your leisure. Unfortunately, in the real world, we often get those "Help! It isn't working!" calls at the most inconvenient times and are under pressure to figure out what's wrong and fix it now.

In this chapter, we address specific problems that commonly occur in conjunction with ISA Server. Even though these issues and diagnosis are specific to the ISA server, the methodologies used can help you troubleshoot any firewall. These problems are divided into logical categories so that you can more easily use this chapter as a reference in the field.

Troubleshooting Guidelines

Many professions exist for the purpose of solving problems of one sort or another. When people have legal problems, they call an attorney. When they have medical problems, they visit a doctor.