Cisco Press 201 W 103rd Street Indianapolis, IN 46290 USA CCNP Support Exam Certification Guide Amir S. Ranjbar, MSc. ii CCNP Support Exam Certification Guide Amir S. Ranjbar, MSc. Copyright© 2001 Cisco Systems, Inc. Cisco Press logo is a trademark of Cisco Systems, Inc. Published by: Cisco Press 201 West 103rd Street Indianapolis, IN 46290 USA All rights reserved. No part of this book may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or by any information storage and retrieval system, without written permission from the publisher, except for the inclusion of brief quotations in a review. Printed in the United States of America 1 2 3 4 5 6 7 8 9 0 First printing October 2000 Library of Congress Cataloging-in-Publication Number: 00-105174 ISBN: 0-7357-0995-5 Warning and Disclaimer This book is designed to provide information about building scalable Cisco networks. 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We greatly appreciate your assistance. iii Publisher John Wait Editor-in-Chief John Kane Executive Editor Brett Bartow Cisco Systems Program Manager Bob Anstey Managing Editor Patrick Kanouse Development Editors Andrew Cupp Howard Jones Technical Editors Elan Beer Steve Kalman Book Designer Gina Rexrode Cover Designer Louisa Klucznik Editorial and Production Team Argosy Indexer Tim Wright Copyright © 1999 Cisco Systems, Inc. All rights reserved. Printed in the USA. 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Parc Evolic, Batiment L1/L2 16 Avenue du Quebec Villebon, BP 706 91961 Courtaboeuf Cedex France http://www-europe.cisco.com Tel: 33 1 69 18 61 00 Fax: 33 1 69 28 83 26 American Headquarters Cisco Systems, Inc. 170 West Tasman Drive San Jose, CA 95134-1706 USA http://www.cisco.com Tel: 408 526-7660 Fax: 408 527-0883 Asia Headquarters Nihon Cisco Systems K.K. Fuji Building, 9th Floor 3-2-3 Marunouchi Chiyoda-ku, Tokyo 100 Japan http://www.cisco.com Tel: 81 3 5219 6250 Fax: 81 3 5219 6001 iv About the Author Amir S. Ranjbar (CCNP) is an instructor and senior network architect for Global Knowledge, Cisco’s largest training partner. He is a Certified Cisco Systems Instructor (CCSI) who teaches the Cisco Internetwork Troubleshooting course on a regular basis. Born in Tehran, Iran, Amir moved to Canada in 1983 and obtained his Bachelors degree in Computing and Information Science (1988) and Master of Science degree in Knowledge Based Systems (1991) from the University of Guelph (Guelph, Ontario). After graduation, Amir developed software applications in the areas of statistical analysis and systems simulation for a number of institutes such as Statistics Canada, University of Waterloo, and University of Ottawa. Amir started his training career by joining Digital Equipment Corporation’s Learning Services in 1995, and after a few years of working exclusively as a Microsoft Certified Trainer (MCSE, MCT), he decided to shift his focus to Cisco Systems’ internetworking products. In 1998, Amir joined Geotrain Corporation, which was acquired by Global Knowledge in 1999. Currently, Amir, already a CCNP, is preparing for the CCIE examinations and is a full-time instructor for Global Knowledge. Among the courses Amir teaches are Interconnecting Cisco Network Devices (ICND), Building Scalable Cisco Networks (BSCN), Building Cisco Remote Access Networks (BCRAN), Cisco Internetwork Troubleshooting (CIT), OSPF, and BGP. You can contact Amir by email at amir.ranjbar@globalknowledge.com. About the Technical Reviewers Elan Beer , CCIE #1837, is president and founder of Synaptic Solutions, Inc. For the past 14 years, Elan has held several key positions within the telecommunications industry, including Senior Telecommunication Consultant, Project Manager, and Telecommunications Instructor, as well as Canadian Training Manager with GeoTrain Corporation, a multinational training and consulting organization. Through his global consulting and training engagements, Elan is recognized internationally as a telecommunications industry expert. Elan’s strong technical skills have enabled him to attain several top-level industry certifications, including Cisco System’s top-level certification, the Cisco Certified Internetwork Expert (CCIE). As one of the first product- based public Certified Cisco Instructors in the world, Elan has utilized his expertise in multiprotocol internetworking, LAN, WAN, and MAN technology, network management, and software engineering to provide training and consulting services to many of Canada’s top companies. As a senior trainer and course developer, Elan has designed and presented intensive public and implementation-specific technical courses for clients in North America, Europe, Australia, Africa, Asia, and Scandinavia. Steve Kalman is a data communications trainer. He is the author or technical editor of 12 CBT titles and has been the author, technical editor, or trainer for eight instructor-led courses. Steve is also beginning a new distance-learning project as both author and presenter. In addition to those responsibilities, he runs a consulting company, Esquire Micro Consultants, that specializes in data network design. v Dedication I would like to dedicate my first book to all those who strive freedom of thought, applaud creative thinking, and respect others’ opinions. Among those are my parents, my wife Elke, and other good family members and friends of mine, who are my treasures. I wish that my children, Thalia, Ariana, and Armando, grow up to be independent, creative, and respectful individuals, and hence, become treasures of tomorrow. vi Acknowledgments I did not have the pleasure of getting to know or communicating with all of the individuals that have put their valuable time and effort into this book, but I would like to use this opportunity to sincerely thank each and every one of them. Among those who I did directly work with was Brett Bartow, whose patience, professionalism, and understanding I will never forget. Brett played a key role in the development of this book from the very beginning. Thanks to Andrew Cupp for his sharp eyes and valuable corrections and suggestions. Also, thanks to Howard Jones and Patrick Kanouse. I feel very lucky that Elan Beer and Steve Kalman joined this team as the technical reviewers. vii Contents at a Glance Introduction xvii Chapter 1 Support Resources for Troubleshooting 3 Chapter 2 Understanding Troubleshooting Methods 33 Chapter 3 Identifying Troubleshooting Targets 49 Chapter 4 Applying Cisco Troubleshooting Tools 101 Chapter 5 Diagnosing and Correcting Campus TCP/IP Problems 159 Chapter 6 Diagnosing and Correcting Novell Networking Problems 189 Chapter 7 Diagnosing and Correcting AppleTalk Problems 215 Chapter 8 Diagnosing and Correcting Catalyst Problems 241 Chapter 9 Troubleshooting VLANS on Routers and Switches 285 Chapter 10 Diagnosing and Correcting Frame Relay Problems 307 Chapter 11 Diagnosing and Correcting ISDN BRI Problems 345 Appendix A Answers to Quiz Questions 389 Index 460 viii Table of Contents Introduction xvii Chapter 1 Support Resources for Troubleshooting 3 “Do I Know This Already?” Quiz 3 Foundation Topics 6 Network Media Test Equipment 6 Network Monitors 7 Protocol Analyzers 8 Network Management Systems 10 CiscoWorks 11 CiscoWorks for Switched Internetworks Software 12 TrafficDirector Remote Monitoring Software 12 Simulation and Modeling Tools 13 Cisco Connection Online (CCO) 13 Using CCO to Prevent Problems 15 Cisco Documentation CD-ROM 15 Cisco MarketPlace 16 CCO Software Library 17 Using CCO to Correct Problems 18 CCO Bug Toolkit 18 CCO Troubleshooting Engine 20 CCO Stack Decoder 20 CCO Open Forum 20 Escalation to Cisco Service and Support 22 CCO Case Management Toolkit 23 Foundation Summary 24 Q&A 26 Chapter 2 Understanding Troubleshooting Methods 33 “Do I Know This Already?” Quiz 33 Foundation Topics 36 The Importance of Using a Systematic Troubleshooting Method 36 ix A Problem-Solving Model 36 Define the Problem 37 Gather the Facts 38 Consider the Possibilities 39 Create an Action Plan 39 Implement Your Action Plan 39 Observe the Results 40 Iterate the Process 40 Resolution 41 A Baseline Model of the Network 41 Foundation Summary 42 Q&A 45 Chapter 3 Identifying Troubleshooting Targets 49 “Do I Know This Already?” Quiz 49 Foundation Topics 52 Understanding Data Link Troubleshooting Targets 52 Troubleshooting Physical and Data Link Protocol Characteristics 52 Clearing Interface Counters 53 The show interfaces Command 54 The show interfaces ethernet n Command 55 The show interfaces tokenring n Command 62 The show controllers Command 64 The show controller token Command Section 1 65 The show controller token Command Section 2 66 The show controller token Command Section 3 66 Token Ring Soft Errors 67 The show interfaces fddi Command 68 The show interfaces atm Command 73 Cisco Discovery Protocol 75 Common Protocol Characteristics 76 Understanding Protocol Connection Troubleshooting Targets 78 TCP Connection Sequence 78 x The show ip arp Command 79 Novell Connection Sequence 80 The show novell traffic Command 81 AppleTalk Connection Sequence 82 The show appletalk traffic Command 82 Foundation Summary 84 Q&A 90 Chapter 4 Applying Cisco Troubleshooting Tools 101 “Do I Know This Already?” Quiz 101 Foundation Topics 105 System Impact of Cisco Troubleshooting Tools 105 Cisco Routers’ Routing Processes and Switching Processes 105 Switching in 7000, 7500, 4000, 3000, and 2500 Series Routers 107 Switching in 7000 Series Routers 108 Switching in 7500 Series Routers 110 Netflow Switching 112 Switching in 4000, 3000, and 2500 Series Routers 112 Process-Switched Packets 114 Handling the Cisco IOS Debug Troubleshooting Tool 115 Using an Access List with Debug 116 Error Message Logging and Limiting the Display of Error Messages 117 show logging Command 121 Reachability and Step-by-Step Path Tests 121 ping Command (IP) (User and Privileged) 121 ping Command (IPX and AppleTalk) 124 traceroute Command (IP) (User and Privileged) 125 Information Needed by Technical Support 126 show version Command 127 Buffers and Queues 129 Buffers and Queues (Cisco 7000/7010) 130 Buffers and Queues (Cisco 4000/3000/2500) 132 show buffers Command 132 [...]... becoming CCNP certified Cisco strongly recommends that you attend its CCNP training courses before taking the CCNP exams Table I-1 shows these courses and how they roughly map to the various exams Cisco Press publishes coursebooks and Exam Certification Guides like this one to support your preparation for these exams Table I-1 Cisco Courses and Exams for CCNP Routing and Switching Certification Course Exam. .. Cisco Certified Network Professional (CCNP) certification in the Routing and Switching career track The other three exams are the Routing (640-503), Switching (640-504), and Remote Access (640-505) exams Optionally, you can take one exam that combines these three exams, Foundation 2.0 (640-509), but you will still need to pass the Support exam separately to attain CCNP status Also note that Cisco Certified... objectives of each of those exams My students often ask me how I think the Support exam is different from the old CIT 4.0 exam My answer is that I did not notice much change; therefore, any training material that can enhance your knowledge of the subjects covered in Cisco’s instructor-based CIT course is still very much valid and useful The Support (640-506) exam is one of the four exams you will need to... prepare yourself for the Cisco Certification examinations This book’s specific target is the Support exam (formerly the Cisco Internetwork Troubleshooting [CIT] Exam) I am a Certified Cisco Systems Instructor, and CIT is one of the courses that I teach I started teaching this course in the first quarter of 1999 I have passed both the old CIT 4.0 and the new Support exams, and I am fully familiar with the structure,... want a condensed, exam- oriented book to prepare them for the CCNP Support exam On the other hand, very often a great portion of my students who have thoroughly enjoyed the CIT course they have taken express their desire to have my discussions and presentation in a written and organized format This book provides that, too Indeed, the material adds explanations, output, configuration examples, and exercises... prepare myself for the exams that I attempt However, we are not all the same, and we do not all have the same budget, time, or learning behaviors What I can tell you with all honesty is that the material presented in this book more than prepares you for the Support exam I can’t and won’t, in good conscience, tell you that this book is all you need to have in order to pass the Support exam, even though it... its CD is a concentrated effort to present the materials specifically in exam- preparation format— review summaries, examples, quiz questions, and so on I have packed this book with questions and answers, quizzes, examples, and tables to make sure that you not only understand the material but also get fully prepared for the Support examination After this brief introductory material, there are 11 chapters... extra attention as they are given a special weight in the Support exam Chapter 11 Troubleshooting ISDN BRI is the topic of this final chapter The Support exam has developed a reputation for being quite heavy on the ISDN topic For that reason, in this chapter I gave my utmost effort to both teach the topics and prepare the audience for a successful exam result Introduction xxi Appendix A This appendix... installation guides Cisco Management Information Base (MIB) User Quick Reference and Access Services Quick Configuration Guide Router and hub installation and configuration guides Switch installation and configuration guides, switch command reference guides, and switch MIB reference guides Configuration notes for memory upgrades, network interface cards, rack-mount kits, and other field upgrade products... better level of understanding of these technologies From there, I will show you the methodology of support, what tools you have available, and how to apply them to specific networks Throughout the book, I present what I think is absolutely essential for you to know before you attempt the CCNP Support exam This book makes a strong companion to the CIT course and the Cisco Internetwork Troubleshooting . Street Indianapolis, IN 46290 USA CCNP Support Exam Certification Guide Amir S. Ranjbar, MSc. ii CCNP Support Exam Certification Guide Amir S. Ranjbar, MSc coursebooks and Exam Certification Guides like this one to support your preparation for these exams. Table I-1 Cisco Courses and Exams for CCNP Routing and