CCNP 4: Network Troubleshooting Companion Guide (Cisco Networking Academy Program)
- By Cisco Systems, Inc., Wayne Lewis
- Published Nov 5, 2004 by Cisco Press. Part of the Companion Guide series.
Book
- Sorry, this book is no longer in print.
- Copyright 2005
- Edition: 1st
- Book
- ISBN-10: 1-58713-141-2
- ISBN-13: 978-1-58713-141-7
The only authorized textbook for the Cisco Networking Academy Program
CCNP 4: Network Troubleshooting Companion Guide contains all the information from the online curriculum. With this Companion Guide, you have access to the course information anytime, anywhere, plus the following reference, study, and review tools:
- Chapter Objectives indicate key concepts for focused study.
- Highlighted key terms throughout the chapter where they are used in context. A comprehensive glossary provides key term definitions to serve as a study aid.
- "Check Your Understanding" review questions, presented at the end of each chapter, act as a review and study guide. They reinforce the concepts introduced in the chapter and help test your understanding before you move on to a new chapter.
- The answers to the questions are provided in an appendix.
- Lab activities from the CCNP 4: Network Troubleshooting Lab Companion are referenced throughout the book. Completing these labs gives you hands-on experience so that you can apply theory to practice.
This Cisco authorized textbook is a portable desk reference designed to complement the CCNP 4: Network Troubleshooting course in the Cisco Networking Academy Program. The topics covered include documentation, baselining, troubleshooting tools, troubleshooting methodologies, and per-OSI-layer troubleshooting techniques. Use this Companion Guide to help prepare for the Cisco Internetwork Troubleshooting exam (642-831), which is one of the four required exams to obtain the CCNP certification.
Companion Title:
CCNP 4: Network Troubleshooting Lab Companion
ISBN: 1-58713-142-0
Companion CD-ROM
The CD-ROM contains a test bank with 200 practice exam questions exclusive to Cisco Press covering topics for the CCNP CIT 642-831 exam. The test engine is powered by Boson Software, Inc., a Cisco Learning Partner. www.boson.com
This book is part of the Cisco Networking Academy Program Series from Cisco Press. The products in this series support and complement the Cisco Networking Academy Program.
Table of Contents
Introduction.
1. Documenting and Baselining the Network.
Network Baselining.
Network Baselining Overview.
Planning for the First Baseline.
Identifying Devices and Ports of Interest.
Determining the Duration of the Baseline.
Using the Baseline Data.
Identifying Undesired Network Behavior.
Identifying Thresholds.
Predicting Long-Term Performance and Capacity Trends.
Verifying Policies.
Network Configuration Documentation.
Network Configuration Documentation Overview.
Identifying the Components of a Network Configuration Table.
Identifying the Components of a Topology Diagram.
Discovering Network Configuration Information.
Describing the Process of Creating Network Documentation.
Creating Network Documentation.
End-System Configuration Documentation.
Identifying the Components of an End-System Network Configuration Table.
Identifying the Components of an End-System Topology Diagram.
Identifying Commands and Applications Used to Discover Information about End-System Configurations.
Discovering End-System Configuration Information.
Creating End-System Network Configuration Documentation.
Summary.
Key Terms.
Check Your Understanding.
2. Troubleshooting Methodologies and Tools.
Using a Layered Architectural Model to Describe Data Flow.
Encapsulating Data.
Bits on the Physical Medium.
Network Devices Utilize Control Information.
Decapsulation.
OSI Model Versus TCP/IP Model.
Position of Network Devices in Layered Model.
Troubleshooting Approaches
General Troubleshooting Process.
Bottom-Up.
Top-Down.
Divide and Conquer.
Guidelines for Selecting an Approach.
Gathering Symptoms.
Gathering Symptoms for a Network Problem.
Gathering Symptoms from an End User: Hardware.
Gathering Symptoms from an End User: Software.
Questions to Ask an End User.
Flow Charts for Gathering Network and End-System Symptoms.
Network Management Tools.
Network Management System Frameworks.
Knowledge-Base Tools.
Performance Measurement and Reporting Tools.
Event and Fault Management Tools.
Policy Management Tools.
Summary.
Key Terms.
Check Your Understanding.
3. Troubleshooting at the Physical Layer.
Characteristics of Physical Layer Failure Problems.
Critical Characteristics–Connectivity.
Critical Characteristics–Upper Layer Component Operation.
Noncritical Characteristics–Equipment Indicators.
Noncritical Characteristics–Power Failures.
Noncritical Characteristics–Console Messages.
Characteristics of Physical Layer Optimization Problems.
Performance Lower Than Baseline.
Exceeding Cable Design Limits, Poor-Quality Cabling, and Connections.
Noise.
Collisions.
Other Data Transmission Issues.
Resources.
Utilization.
Console Messages.
Windows and Cisco Commands for Physical Layer Information Gathering.
End-System Commands–Common Commands.
End-System Commands–Windows Only.
End-System Commands–UNIX/Mac OS.
Common Cisco IOS Commands.
Cisco IOS show Commands.
Identifying Physical Layer Problems.
Power-Related.
Cabling Faults–Cat5.
Cabling Faults–Fiber and Coax.
Hardware.
Collision-Based Problems–Shared Media.
External Interference.
Configuration Script Errors.
CPU Overload.
Isolating Physical Layer Problems.
Methodology.
Tools for the Job.
Bad Cabling.
Cabling Incorrect.
Interface Configuration.
Operational Statistics.
Implementing Physical Layer Solutions.
Solving Common Problems–Methodology.
ARP Commands.
Solving Common Problems–Windows and UNIX/Mac OS EndSystem Commands.
Solving Common Problems–Cisco IOS Commands.
Redundancy.
Solving Common Problems–Support Resources.
Summary.
Key Terms.
Check Your Understanding.
4. Layer 2 Troubleshooting.
Characteristics of Data-Link Layer Problems.
Data-Link Layer Problems Overview.
No Component Above the Data-Link Layer Is Functional.
The Network Is Functional, But Operating at Less Than the Baseline Level.
Framing Errors.
Encapsulation Errors.
Layer 2-to-Layer 3 Address Mapping Errors.
Critical Characteristics–No Network Layer Connectivity.
Upper Layer Component Operation.
Critical Characteristics–Console Messages.
End-System Commands for Gathering Data-Link Layer Information.
Common End-System Commands.
Microsoft Windows End-System Commands.
UNIX/Mac Operating System End-System Commands.
General Cisco IOS Commands.
Cisco IOS show Commands.
The show cdp neighbors Command.
Troubleshooting Switched Ethernet Networks.
Troubleshooting the Spanning Tree Protocol.
Troubleshooting STP Loops.
Preventing STP Loops.
Troubleshooting Incorrect STP Root Configuration.
Troubleshooting Ethernet Broadcast Traffic.
Troubleshooting Ethernet Switch Flooding.
Troubleshooting VTP Misconfiguration.
Troubleshooting EtherChannel.
Troubleshooting ISDN.
T1 Framing Errors.
Troubleshooting ISDN Primary Rate Switch Types.
Troubleshooting ISDN BRI-to-Telco Communications.
Troubleshooting ISDN BRI Dialer Problems.
Debugging ISDN Call Setup Failures.
Troubleshooting Frame Relay.
Steps for Troubleshooting Frame Relay.
The show frame-relay lmi Command.
The show frame-relay pvc Command.
Frame Relay Encapsulation Type.
Troubleshooting Frame Relay Using the Line Status.
Ping the Local IP Address with Multipoint Frame Relay.
Reconfiguring a Subinterface.
PPP and Layer 2 Considerations for Routed and Routing Protocols.
Link Control Protocol.
Troubleshooting PPP Authentication PAP.
Troubleshooting PPP Authentication CHAP.
IP Split Horizon Checking.
OSPF in an NBMA Environment.
The Keyword broadcast.
Excessive Fragmentation.
Summary.
Key Terms.
Check Your Understanding.
5. Layer 3 Troubleshooting.
Troubleshooting Network Layer Problems.
What Are Network Layer Problems?.
Isolating the Problem Methodology.
Static Routes, Dynamic Routing, Summarization, Redistribution, and Combinations.
Troubleshooting Static Routes.
Static Routes and Classful Lookups.
Static Routes and Intermediate Addresses.
Static Route Optimization with Serial Networks.
Static Route Optimization with Ethernet Networks.
Recurring Static Route Installation and Deletion.
Using Discard Routes.
Common IGP Routing Protocol Issues, Causes, and Solutions.
Introduction.
Missing or Incorrect network or neighbor Statement.
Layer 1 or 2 Is Down.
Distribute List In/Out Blocking.
Access List Blocking.
Advertised Network Interface Is Down.
Passive Interface.
Troubleshooting RIP.
Incompatible RIP Version Types.
Mismatched Authentication Key.
Reaches RIP Hop Count Limit.
Discontiguous Networks.
Invalid Source Address.
Flapping Routes.
Large Routing Tables.
Troubleshooting IGRP.
Discontiguous Networks.
AS Mismatch.
Misconfigured neighbor Statement.
Maximum Paths.
Candidate Default.
Troubleshooting EIGRP.
Mismatched K Values.
Mismatched AS Number.
Stuck in Active–Determining the Problem.
Stuck in Active–Methodology for Troubleshooting.
Stuck in Active–The Ultimate Solution.
Duplicate Router IDs.
EIGRP Error Messages.
Troubleshooting OSPF.
Mismatched Parameters.
OSPF State Issues.
One Side of the Point-to-Point Link Is Unnumbered.
ABR Is Not Generating a Type 4 Summary LSA.
Forwarding Address Is Not Known Through the Intra-Area or Interarea Route.
Route Summarization Problems.
CPUHOG Problems.
SPF Calculation and Route Flapping.
Troubleshooting IS-IS.
IS-IS Adjacency Problems.
Some or All of the Adjacencies Are Not Coming Up.
Adjacency Is Stuck in INIT State.
ES-IS Adjacency Formed Instead of IS-IS Adjacency Formed.
Route Advertisement Problems.
Route Flapping Problem.
Troubleshooting BGP.
Troubleshooting BGP Neighbor Relationship Problems.
Troubleshooting BGP Route Advertisements.
Troubleshooting Routes Are Not Being Installed in the
IP Routing Table.
The BGP Next Hop Is Unreachable.
BGP Routes Getting Dampened.
Troubleshooting Outbound and Inbound BGP Policy Issues.
Traffic Takes a Different Interface Than What Is Shown in the Routing Table.
Troubleshooting Redistribution.
Redistribution Problems with RIP.
Redistribution Problems with IGRP/EIGRP.
Redistribution Problems with OSPF.
Redistribution Problems with IS-IS.
Redistribution Problems with BGP.
Summary.
Key Terms.
Check Your Understanding.
6. Layer 4 Troubleshooting.
Characteristics of Transport Layer Technologies.
Common Transport Layer Technologies.
User Datagram Protocol.
Transport Control Protocol.
Standard Access Control Lists.
Extended Access Control Lists.
Static IP Network Address Translation.
Dynamic IP Network Address Translation.
NetBIOS and NetBEUI.
Troubleshooting Transport Layer Issues on the Router.
Common Issues with Extended ACLs.
Gathering Information on ACL Operation.
Optimizing Access List Operation.
Common Issues with IP NAT.
Gathering Information on NAT Configuration and Operation.
Other Useful Information.
Troubleshooting Transport Layer Issues on Network Hosts.
Common Transport Layer Issues with IP Networks.
Gathering Transport Layer Information on Windows Machines.
Gathering Transport Layer Information on UNIX Machines.
Common Issues with NetBIOS Networks.
Gathering NetBIOS Information.
Troubleshooting Complex Network Systems.
Identifying Complex Transport Layer Problems.
Disassembling the Problem.
Solving the Component Problems.
Dynamic NAT and Extended ACLs.
TCP Load Distribution with NAT.
Summary.
Key Terms.
Check Your Understanding.
7. Layer 1—7 Troubleshooting.
Troubleshooting at the Application Layer.
Overview.
Troubleshooting at the Application Layer.
Overview.
Eliminating Layers 1—3.
Eliminating Layer 4.
Isolating Application Layer Problems.
Identifying Support Resources.
Accessing Support Resources.
Correcting Application Layer Problems.
Gathering Information on Application Layer Problems.
Overview.
Common TCP/IP Commands.
Platform-Specific TCP/IP Utilities.
Cisco IOS Commands.
System Logs.
Syslog Destinations.
Deciphering Syslog Messages.
Protocol Analyzers.
Network Management Systems.
Troubleshooting TCP/IP Application Layer Protocols.
Overview.
Client/Server Systems.
Terminals and Consoles.
Web Traffic.
Electronic Mail.
File Transfer.
Network Management and Time Protocols.
Name Resolution.
Dynamic Host Configuration Protocol (DHCP).
Troubleshooting TCP/IP Application Layer Problems.
Troubleshooting Telnet Problems.
Troubleshooting HTTP Problems.
Troubleshooting E-Mail Problems.
Troubleshooting FTP Problems.
Troubleshooting DNS Problems.
Summary.
Key Terms.
Check Your Understanding.
Appendix A: Check Your Understanding Answer Key.
Appendix B: Catalyst OS Troubleshooting.
Glossary
Index