Learn how to troubleshoot slowdowns and crashes on Cisco routers

This chapter from Cisco Routers for the Desperate describes how to troubleshoot router problems that can compromise your network services.

Day-to-day router problems can be boiled down into two groups:

• Router crashes
• Network failure or slowness

What steps should you take if a router crashes? Among the suggestions in this sample chapter: Attach the serial console to the router and leave it there. A crashing router will often print errors to the serial console, and any crash messages will remain in the serial terminal's message buffer. Copy the messages exactly, and search on them in Google or http://www.cisco.com; you may well identify the problem.

Network failure is a far more common reason for router problems, and the chapter devotes most of its attention to exploring a variety of troubleshooting techniques you can use to identify the cause of circuit outages. It also explains the physical design of a modern T1 circuit, how to take advantage of router interface debugging information, and ways to determine whether the problem is on your end or with your ISP or telco.

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  Title: Cisco Routers for the Desperate
• ISBN: ISBN: 1-59327-049-6
• Published: December 2004; No Starch Press
• Author: Michael W. Lucas
• Chapter: Chapter 5, Troubleshooting Routers

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