Introduction

This chapter focuses on troubleshooting PIX firewalls. Once you have mastered its command syntax and basic firewall operations, the PIX is a relatively simple device to configure. Its library of commands is small compared to that of Cisco routers and switches. In previous chapters, we covered the PIX firewall in detail, from the various models in the product line to simple and advanced configurations. This book contains information on how to integrate the PIX firewall into your existing network. As good as your PIX configuration is, problems will still crop up, and you need to know how to resolve them. The purpose of this chapter is to present a methodology that you can use to attack these problems and avoid missing critical troubleshooting steps.

Hardware and cabling problems can be a bane to an otherwise well-functioning network. A hardware problem becomes apparent if you know which indicators to monitor. The limited number of cable types that the PIX supports eases our cable troubleshooting considerably. This chapter provides technical information about these cables so you can validate them.

The PIX firewall is an IP device. Granted, it is a highly specialized device that performs vital security functions, but it is still an IP device. As such, it needs to know where to send traffic. We highlight some common connectivity problems and how you can address them. A valuable function of the PIX firewall is its ability to conserve IP address space and hide network details via Network Address Translation (NAT).