CHAPTER
5-1
Cisco 7401ASR Installation and Configuration Guide
OL-5419-01 B0
5
Troubleshooting
Your Cisco7401ASR router went throu gh extensive testing before leaving the facto ry. However, if you
encounter problems starting the router, use the information in this chapter to help isola te the cause o f the
problems. This chapter contains the following sections:
•Troubleshooting Overview, page 5-1
•Problem Solving Using a Subsystems Approach, page 5-2
•Upgrading the Boot Helper (Boot Loader) Image, page 5-7
•PXF Troubleshooting Information, page 5-8
The procedures in this chapter assume that you are troubleshooting the initial sy stem start up, an d that
your router is in the original factory configuration. If you have removed or re plac ed co mpo ne nts o r
changed any default settings, the recommendations in this chapter might not apply. Make sure to review
the safety warnings listed in the publication Cisco7401ASR Regulatory Comp liance and Safety
Information that accompanied your Cisco 7401ASR router before using the troubleshooting procedures
in this chapter.

Troubleshooting Overview

This section describes the troubleshooting methods used in this chapter and describes how the
Cisco 7401ASR router is divided into subsystems for more efficient problem solving. If you are unable
to easily solve the problem, contact a customer service representative for assistance and further
instructions. Provide the representative with the following information:
•Date you received the router
•Chassis serial number
•Type of software and release number
•Brief description of the problem you are having
•Brief explanation of the steps you have taken to isolate and resolve the problem
•Maintenance agreement or warranty information
The following table shows the general troubleshooting strategy described in this appendix. Refer to this
table, as necessary, to follow the steps to isolate problems to a specific subsystem; resolve the problem
if possible.