Table Of Contents

Preface

Changes to This Document

Obtaining Documentation and Submitting a Service Request

Preface

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This guide describes how to troubleshooting a router using the Cisco IOS XR software.

This preface contains the following sections:

•Changes to This Document

•Obtaining Documentation and Submitting a Service Request

Changes to This Document

lists the technical changes made to this document since it was first issued.

Table 1 Changes to This Document 

Revision	Date	Change Summary
OL-21483-02	October, 2010	Added information about the following topics: •Chapter 1—Added links to information on SNMP timeouts and the MIBs download site. •Chapter 1—Added a list of commands to use to gather information prior to contacting TAC. •Chapter 4—Added a drawing of the fabric architecture. •Chapter 4—Added information about using online diagnostics to help troubleshoot fabric. •Chapter 4—Added the CLI command show controllers fabric link health. •Chapter 4—Added information about using the correct fiber cleaning kit and procedure. •Chapter 4—Added a section with guidelines on maintenance of fabric links. Continued, next page
OL-21483-02	October, 2010	(Continued from previous page) •Chapter 5—Added a section on troubleshooting the line card optical interfaces (pluggable-optics). •Chapter 6—Added information on using online diagnostics to help troubleshoot the Ethernet control plane. •Chapter 7—Added CLI commands for displaying online diagnostics. •Chapter 7—Added a note about online diagnostics behavior after an RP failover. •Chapter 8—Added details on SNMP timeouts. •Chapter 8—Added information on normal and abnormal causes of high CPU utilization. •Chapter 10—Added clarifications regarding software and firmware upgrades.
OL-21483-01	December, 2009	Initial release of this document.

Obtaining Documentation and Submitting a Service Request

For information on obtaining documentation, submitting a service request, and gathering additional information, see the monthly What's New in Cisco Product Documentation, which also lists all new and revised Cisco technical documentation, at:

http://www.cisco.com/en/US/docs/general/whatsnew/whatsnew.html

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