Cover image for Cisco Internetwork troubleshooting
Cisco Internetwork troubleshooting
Chappell, Laura.
Personal Author:
Publication Information:
Indianapolis, Ind. : Cisco, 1999.
Physical Description:
xvi, 604 pages : illustrations ; 24 cm
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TK5105.5 .C42 1999 Adult Non-Fiction Central Closed Stacks

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The Cisco Internetwork Troubleshooting course is recommended training for CCNP certification candidates. This book serves as a supplement for those who have taken the course and a replacement for those who choose not to. It includes troubleshooting exercises to simulate the labs in the CIT course.

Author Notes

Laura Chappell , senior protocol analyst, is a highly energetic speaker and author who has trained thousands of LAN/WAN administrators, engineers, technicians, and developers. Ms. Chappell has provided Cisco training since 1992 and has written numerous books and articles on a variety of networking subjects.

Dan Farkas , CCIE(r) N0. 3800, is a general manager for Advanced Network Information (ANI), a high-quality Cisco Learning Partner. He is CCIE certified and a certified Cisco Systems instructor. For the last five years, Dan has been teaching a variety of network configuration, design, and troubleshooting classes, including various router, LAN switching, and voice/data integration classes.

Table of Contents

Forewordp. xiv
Introductionp. xv
Part 1 Troubleshooting Tools and Methodology
Chapter 1 Troubleshooting Methodologyp. 4
Using a Systematic Troubleshooting Methodp. 5
The Complexity of Internetworksp. 6
The Problem-Solving Modelp. 8
Step 1 Define the Problemp. 10
Step 2 Gather the Factsp. 12
Step 3 Consider the Possibilitiesp. 12
Step 4 Create an Action Planp. 14
Step 5 Implement the Action Planp. 15
Step 6 Observe the Results of the Action Planp. 16
Step 7 Repeat the Problem-Solving Processp. 16
Step 8 Resolve the Problemp. 18
Preparing Yourself to Troubleshootp. 18
Chapter 2 Protocol Characteristics Overviewp. 24
Basic Protocol Characteristicsp. 25
Connection-Oriented Servicesp. 26
Connectionless Servicesp. 27
Sample Connection Sequencesp. 28
Detailed Protocol Characteristicsp. 33
Connection-Oriented Versus Connectionless Protocolsp. 35
OSI Layer 2 Characteristicsp. 39
OSI Layers 3 to 7 Characteristics--Routed Protocols and Routing Protocolsp. 92
Chapter 3 Cisco Routing and Switching Processesp. 150
Routingp. 151
Switchingp. 153
Basic Switching Pathsp. 154
Sample Packet Flowp. 159
Switching Features That Affect Performancep. 162
Process Switchingp. 164
System Buffering and Queuingp. 165
Input and Output Queuesp. 167
Interface Buffersp. 168
Chapter 4 General Troubleshooting Toolsp. 172
Low-End Cable Test Equipmentp. 173
High-End Cable Testersp. 175
Digital Interface Testing Toolsp. 176
Network Monitorsp. 177
Protocol Analyzersp. 178
Network Management Systemsp. 180
Simulation and Modeling Toolsp. 182
Chapter 5 Cisco Management and Diagnostic Toolsp. 186
Cisco Management Toolsp. 187
Cisco Worksp. 187
The Netsys Network Management Suitesp. 190
TrafficDirector Remote Monitoring Softwarep. 192
The VlanDirector Switch Management Applicationp. 194
WAN Managerp. 195
Cisco Diagnostic Commandsp. 196
show Commandsp. 198
debug Commandsp. 221
Ping and trace Commandsp. 229
The cdp Commandp. 240
Core Dumpsp. 252
Chapter 6 Troubleshooting Sample Exercisesp. 256
Exercise 1 A Token Ring Networkp. 257
Exercise 2 The Sydney Routerp. 259
Exercise 3 The Brussels Routerp. 262
Part II Routing and Routed Protocol Troubleshooting
Chapter 7 Troubleshooting TCP/IP Connectivityp. 274
TCP/IP Router Diagnostic Toolsp. 275
The TCP/IP ping Commandp. 275
The TCP/IP trace Commandp. 280
TCP/IP show Commandsp. 282
TCP/IP debug Commandsp. 294
Problem Isolation in TCP/IP Networksp. 302
Symptom: Users Can Access Some Hosts but Not Othersp. 303
Symptom: Users Cannot Connect When One Redundant Path Is Downp. 305
Troubleshooting IP Internetworking with Windows NTp. 306
Browsing Problemsp. 307
TCP/IP Symptoms and Problemsp. 308
TCP/IP Problems and Action Plansp. 309
Pinging Your Loopback and Local IP Addressesp. 313
Pinging Your Cisco Routerp. 313
Pinging the DNS Server, Default Gateway, and WINS Serverp. 313
Pinging the Remote Target IP Addressp. 314
The tracert Toolp. 314
Checking the Routing Table on a Windows NT Systemp. 315
Clearing the Windows NT System ARP Cachep. 316
DNS Configurationp. 316
The HOSTS Filep. 317
The LMHOSTS Filep. 317
Winsock Proxy Problemsp. 317
Chapter 8 Troubleshooting Novell Connectivityp. 322
Novell NetWare Router Diagnostic Toolsp. 323
The IPX ping Commandp. 323
The IPX show Commandsp. 324
The IPX debug Commandsp. 338
Problem Isolation in NetWare Networksp. 345
NetWare Symptoms and Problemsp. 347
Troubleshooting Encapsulation Mismatchesp. 348
NetWare Problems and Action Plansp. 349
Chapter 9 Troubleshooting AppleTalk Connectivityp. 356
AppleTalk Router Diagnostic Commandsp. 357
AppleTalk show Commandsp. 357
NBP Testingp. 374
AppleTalk debug Commandsp. 376
Problem Isolation in AppleTalk Networksp. 385
AppleTalk Symptoms and Problemsp. 386
AppleTalk Problems and Action Plansp. 388
AppleTalk Internetworking Configuration Tipsp. 392
Part III Campus Switch and VLAN Troubleshooting
Chapter 10 Diagnosing and Correcting Catalyst Problemsp. 398
Catalyst Series Overviewp. 399
Catalyst 5000 Internal Architecturep. 401
Catalyst Switching Technologyp. 404
Spanning-Tree Reviewp. 406
VLAN Frame Tagging with ISLp. 408
Catalyst 5000 Troubleshooting Toolsp. 415
Troubleshooting Catalyst Switch LEDsp. 418
Catalyst 5000 Switch Diagnostic Tools: pingp. 421
CDPp. 421
SPANp. 423
Catalyst Commandsp. 425
show Commands for System Settingsp. 426
show Commands for Switch Configurationp. 430
Problem Isolation in Catalyst Networksp. 437
Catalyst Symptoms and Problemsp. 438
Chapter 11 Troubleshooting VLANs on Routers and Switchesp. 442
VLANs on Routed and Switched Networksp. 444
VLAN Switching, Translation, and Routingp. 445
The Router's Layer 2 Translation Functionp. 447
Cisco IOS Fast Ethernet Troubleshootingp. 447
VLAN Troubleshooting Issuesp. 450
VLAN Design Issuesp. 450
Router Functionality in a Switched Networkp. 451
CDPp. 452
Using Telnet to a Switch on a Different Subnetp. 452
Router VLAN show Commandsp. 453
The show vlan Commandp. 454
The show span Commandp. 455
Router VLAN debug Commandsp. 457
The debug vlan packet Commandp. 457
The debug span Commandp. 458
Problem Isolation in Router/Switch VLAN Networksp. 460
Troubleshooting Example: Dropped Packets and Loopsp. 460
Router VLAN Symptoms and Problemsp. 462
Part IV WAN Troubleshooting
Chapter 12 Diagnosing and Correcting Frame Relay Problemsp. 468
Troubleshooting Frame Relayp. 469
Frame Relay Frame Formatp. 471
Problem Isolation in Frame Relay WANsp. 471
Overview of Troubleshooting Commandsp. 474
WAN and Frame Relay Diagnostic Toolsp. 475
The Frame Relay show Commandsp. 475
The Frame Relay debug Commandsp. 480
Frame Relay Loopback Testsp. 485
Chapter 13 Diagnosing and Correcting ISDN BRI Problemsp. 488
Problem Isolation in ISDN BRI Networksp. 489
Overview of Troubleshooting Commandsp. 493
ISDN BRI Diagnostic Toolsp. 493
ISDN BRI show Commandsp. 493
ISDN BRI debug Commandsp. 505
Part V Appendixes
Appendix A Chapter Test Answer Keyp. 530
Appendix B Cisco Support Functionsp. 542
Using CCO to Prevent Problemsp. 545
Cisco Documentationp. 546
Cisco Pressp. 547
CCO MarketPlacep. 547
CCO Software Centerp. 548
Using CCO to Correct Problemsp. 548
Cisco's Bug Toolkit IIp. 549
CCO Troubleshooting Enginep. 549
CCO Stack Decoderp. 550
CCO Open Forump. 550
TACp. 551
CCO Training Informationp. 553
Chapter C References and Recommended Readingp. 554
Books and Periodicalsp. 555
Technical Publications and Standardsp. 557
Chapter D Problem-Solving Checklist and Worksheetp. 562
Troubleshooting Checklistp. 563
Troubleshooting Worksheetp. 564
Indexp. 570