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CCNA Portable Command Guide, 2nd Edition

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CCNA Portable Command Guide, 2nd Edition


  • Sorry, this book is no longer in print.
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  • Copyright 2008
  • Edition: 2nd
  • Book
  • ISBN-10: 1-58720-193-3
  • ISBN-13: 978-1-58720-193-6

CCNA Portable Command Guide

Second Edition

All the CCNA 640-802 commands in one compact, portable resource

Preparing for the CCNA® exam? Here are all the CCNA-level commands you need in one condensed, portable resource. The CCNA Portable Command Guide, Second Edition, is filled with valuable, easy-to-access information and is portable enough for use whether you’re in the server room or the equipment closet.

This book has been completely updated to cover topics in the ICND1 640-822, ICND2 640-816, and CCNA 640-802 exams. Use this quick reference resource to help you memorize commands and concepts as you work to pass the CCNA exam. The guide summarizes all CCNA certification-level Cisco IOS® Software commands, keywords, command arguments, and associated prompts, providing you with tips and examples of how to apply the commands to real-world scenarios. Configuration examples throughout the book provide you with a better understanding of how these commands are used in simple network designs.

The ten topics covered are

  • TCP/IP
  • An Introduction to Cisco Devices
  • Configuring a Router
  • Routing
  • Switching
  • Implementing a Wireless LAN
  • Network Administration and Troubleshooting
  • Managing IP Services
  • WANs
  • Network Security

Scott Empson is currently the associate chair of the bachelor of applied information systems technology degree program at the Northern Alberta Institute of Technology in Edmonton, Alberta, Canada, teaching Cisco® routing, switching, and network design courses in certificate, diploma, and applied degree programs at the post-secondary level. He is also the program coordinator of the Cisco Networking Academy® Program at NAIT, a Regional Academy covering central and northern Alberta. He has earned three undergraduate degrees and currently holds several industry certifications, including CCNP®, CCDA®, CCAI, and Network+®.

  • Access all CCNA commands–use as a quick, offline resource for research and solutions
  • Logical how-to topic groupings provide one-stop research
  • Great for review before CCNA certification exams
  • Compact size makes it easy to carry with you, wherever you go
  • “Create Your Own Journal” section with blank, lined pages allows you to personalize the book for your needs
  • “What Do You Want to Do?” chart inside back cover helps you to quickly reference specific tasks

This book is part of the Cisco Press® Certification Self-Study Product Family, which offers readers a self-paced study routine for Cisco® certification exams. Titles in the Cisco Press Certification Self-Study Product Family are part of a recommended learning program from Cisco that includes simulation and hands-on training from authorized Cisco Learning Partners and self-study products from Cisco Press.

Category: Cisco Press–Cisco Certification

Covers: CCNA Exam (640-822 ICND1, 640-816 ICND2, and 640-802 CCNA)

Sample Content

Online Sample Chapter

CCNA Portable Command Guide: IPv6

Downloadable Sample Chapter

Chapter 25: IPv6

Sample Pages

Download the sample pages (includes Chapter 25 and Index)

Table of Contents


Introduction xxi

Part I TCP/IP Version 4 1

Chapter 1 How to Subnet 3

Class A—E Addresses 3

Converting Between Decimal Numbers and Binary 4

Subnetting a Class C Network Using Binary 4

Subnetting a Class B Network Using Binary 8

Binary ANDing 12

    So Why AND? 14

    Shortcuts in Binary ANDing 15

The Enhanced Bob Maneuver for Subnetting 16

Chapter 2 VLSM 21

IP Subnet Zero 21

VLSM Example 22

    Step 1 Determine How Many H Bits Will Be Needed to

                Satisfy the Largest Network 22

    Step 2 Pick a Subnet for the Largest Network to Use 23

    Step 3 Pick the Next Largest Network to Work With 24

    Step 4 Pick the Third Largest Network to Work With 26

    Step 5 Determine Network Numbers for Serial Links 27

Chapter 3 Route Summarization 29

Example for Understanding Route Summarization 29

    Step 1: Summarize Winnipeg’s Routes 30

    Step 2: Summarize Calgary’s Routes 31

    Step 3: Summarize Edmonton’s Routes 31

    Step 4: Summarize Vancouver’s Routes 32

Route Summarization and Route Flapping 34

Requirements for Route Summarization 34

Part II Introduction to Cisco Devices 35

Chapter 4 Cables and Connections 37

Connecting a Rollover Cable to Your Router or Switch 37

Terminal Settings 37

LAN Connections 38

Serial Cable Types 39

Which Cable to Use? 41

568A Versus 568B Cables 42

Chapter 5 The Command-Line Interface 45

Shortcuts for Entering Commands 45

Using the Tab Key to Complete Commands 45

Using the Question Mark for Help 46

enable Command 46

exit Command 47

disable Command 47

logout Command 47

Setup Mode 47

Keyboard Help 48

History Commands 49

show Commands 49

Part III Configuring a Router 51

Chapter 6 Configuring a Single Cisco Router 53

Router Modes 53

Entering Global Configuration Mode 54

Configuring a Router Name 54

Configuring Passwords 54

Password Encryption 55

Interface Names 56

Moving Between Interfaces 58

Configuring a Serial Interface 59

Configuring a Fast Ethernet Interface 59

Creating a Message-of-the-Day Banner 60

Creating a Login Banner 60

Setting the Clock Time Zone 60

Assigning a Local Host Name to an IP Address 61

The no ip domain-lookup Command 61

The logging synchronous Command 61

The exec-timeout Command 62

Saving Configurations 62

Erasing Configurations 62

show Commands 63

EXEC Commands in Configuration Mode: The do Command 64

Configuration Example: Basic Router Configuration 64

Part IV Routing 67

Chapter 7 Static Routing 69

Configuring a Static Route on a Router 69

The permanent Keyword (Optional) 70

Static Routes and Administrative Distance (Optional) 70

Configuring a Default Route on a Router 71

Verifying Static Routes 72

Configuration Example: Static Routes 72

Chapter 8 RIP 75

The ip classless Command 75

RIP Routing: Mandatory Commands 75

RIP Routing: Optional Commands 76

Troubleshooting RIP Issues 77

Configuration Example: RIPv2 Routing 78

Chapter 9 EIGRP 81

Configuring Enhanced Interior Gateway Routing Protocol (EIGRP) 81

EIGRP Auto-Summarization 82

Load Balancing: variance 83

Bandwidth Use 84

Authentication 84

Verifying EIGRP 86

Troubleshooting EIGRP 86

Configuration Example: EIGRP 87

Chapter 10 Single Area OSPF 91

Configuring OSPF: Mandatory Commands 91

Using Wildcard Masks with OSPF Areas 92

Configuring OSPF: Optional Commands 93

    Loopback Interfaces 93

    Router ID 94

    DR/BDR Elections 94

    Modifying Cost Metrics 95

    Authentication: Simple 95

    Authentication: Using MD5 Encryption 96

    Timers 96

    Propagating a Default Route 96

Verifying OSPF Configuration 97

Troubleshooting OSPF 98

Configuration Example: Single Area OSPF 98

Part V Switching 103

Chapter 11Configuring a Switch 105

Help Commands 105

Command Modes 105

Verifying Commands 106

Resetting Switch Configuration 107

Setting Host Names 107

Setting Passwords 107

Setting IP Addresses and Default Gateways 108

Setting Interface Descriptions 108

Setting Duplex Operation 109

Setting Operation Speed 109

Managing the MAC Address Table 109

Configuring Static MAC Addresses 109

Switch Port Security 110

Verifying Switch Port Security 111

Sticky MAC Addresses 112

Configuration Example 113

Chapter 12 VLANs 117

Creating Static VLANs 117

    Using VLAN Configuration Mode 117

    Using VLAN Database Mode 118

Assigning Ports to VLANs 118

Using the range Command 119

Verifying VLAN Information 119

Saving VLAN Configurations 119

Erasing VLAN Configurations 120

Configuration Example: VLANs 121

Chapter 13 VLAN Trunking Protocol and Inter-VLAN Routing 125

Dynamic Trunking Protocol (DTP) 125

Setting the Encapsulation Type 126

VLAN Trunking Protocol (VTP) 127

    Using Global Configuration Mode 127

    Using VLAN Database Mode 128

Verifying VTP 130

Inter-VLAN Communication Using an External Router: Router-on-a-Stick 130

Inter-VLAN Communication Tips 131

Configuration Example: Inter-VLAN Communication 132

Chapter 14 STP and EtherChannel 139

Spanning Tree Protocol 139

    Enabling Spanning Tree Protocol 139

    Configuring the Root Switch 140

    Configuring a Secondary Root Switch 141

    Configuring Port Priority 141

    Configuring the Path Cost 142

    Configuring the Switch Priority of a VLAN 142

    Configuring STP Timers 143

    Verifying STP 143

    Optional STP Configurations 144

    Changing the Spanning-Tree Mode 145

    Extended System ID 146

    Enabling Rapid Spanning Tree 146

    Troubleshooting Spanning Tree 147

    Configuration Example: STP 147

EtherChannel 150

    Interface Modes in EtherChannel 151

    Guidelines for Configuring EtherChannel 151

    Configuring Layer 2 EtherChannel 152

    Verifying EtherChannel 152

    Configuration Example: EtherChannel 153

Part VI Extending the LAN 159

Chapter 15 Implementing a Wireless LAN 161

Wireless Access Point Configuration: Linksys 300N Access Point 161

Wireless Client Configuration: Linksys Wireless-N Notebook Adapter 174

Part VII Network Administration and Troubleshooting 183

Chapter 16 Backing Up and Restoring Cisco IOS Software and

Configurations 185

Boot System Commands 185

The Cisco IOS File System 186

Backing Up Configurations to a TFTP Server 186

Restoring Configurations from a TFTP Server 187

Backing Up the Cisco IOS Software to a TFTP Server 188

Restoring/Upgrading the Cisco IOS Software from a TFTP Server 188

Restoring the Cisco IOS Software from ROM Monitor Mode Using Xmodem 189

Restoring the Cisco IOS Software Using the ROM Monitor

Environmental Variables and tftpdnld Command 192

Chapter 17 Password-Recovery Procedures and the Configuration Register 193

The Configuration Register 193

    A Visual Representation 193

    What the Bits Mean 194

    The Boot Field 194

    Console Terminal Baud Rate Settings 195

    Changing the Console Line Speed: CLI 195

    Changing the Console Line Speed: ROM Monitor

        Mode 195

Password-Recovery Procedures for Cisco Routers 196

Password Recovery for 2960 Series Switches 198

Chapter 18 Cisco Discovery Protocol (CDP) 201

Cisco Discovery Protocol 201

Chapter 19 Telnet and SSH 203

Using Telnet to Remotely Connect to Other Devices 203

Configuring the Secure Shell Protocol (SSH) 205

Chapter 20 The ping and traceroute Commands 207

ICMP Redirect Messages 207

The ping Command 207

Examples of Using the ping and the Extended ping

    Commands 208

The traceroute Command 209

Chapter 21 SNMP and Syslog 211

Configuring SNMP 211

Configuring Syslog 211

Chapter 22 Basic Troubleshooting 213

Viewing the Routing Table 213

Determining the Gateway of Last Resort 214

Determining the Last Routing Update 214

OSI Layer 3 Testing 214

OSI Layer 7 Testing 215

Interpreting the show interface Command 215

Clearing Interface Counters 215

Using CDP to Troubleshoot 216

The traceroute Command 216

The show controllers Command 216

debug Commands 216

Using Time Stamps 217

Operating System IP Verification Commands 217

The ip http server Command 217

The netstat Command 218

Part VIII Managing IP Services 219

Chapter 23 Network Address Translation 221

Private IP Addresses: RFC 1918 221

Configuring Dynamic NAT: One Private to

    One Public Address Translation 221

Configuring PAT: Many Private to One Public Address

    Translation 223

Configuring Static NAT: One Private to One Permanent

    Public Address Translation 226

Verifying NAT and PAT Configurations 227

Troubleshooting NAT and PAT Configurations 227

Configuration Example: PAT 228

Chapter 24 DHCP 231

Configuring DHCP 231

Verifying and Troubleshooting DHCP Configuration 232

Configuring a DHCP Helper Address 232

DHCP Client on a Cisco IOS Software Ethernet Interface 233

Configuration Example: DHCP 233

Chapter 25 IPv6 237

Assigning IPv6 Addresses to Interfaces 237

IPv6 and RIPng 238

Configuration Example: IPv6 RIP 239

IPv6 Tunnels: Manual Overlay Tunnel 241

Static Routes in IPv6 244

Floating Static Routes in IPv6 245

Verifying and Troubleshooting IPv6 245

IPv6 Ping 247

Part IX WANs 249

Chapter 26 HDLC and PPP 251

Configuring HDLC Encapsulation on a Serial Line 251

Configuring PPP on a Serial Line (Mandatory Commands) 251

Configuring PPP on a Serial Line (Optional Commands): Compression 252

Configuring PPP on a Serial Line (Optional Commands): Link Quality 252

Configuring PPP on a Serial Line (Optional Commands): Multilink 252

Configuring PPP on a Serial Line (Optional Commands): Authentication 252

Verifying or Troubleshooting a Serial Link/PPP

Encapsulation 253

Configuration Example: PPP 254

Chapter 27 Frame Relay 257

Configuring Frame Relay 257

    Setting the Frame Relay Encapsulation Type 257

    Setting the Frame Relay Encapsulation LMI Type 258

    Setting the Frame Relay DLCI Number 258

    Configuring a Frame Relay map Statement 258

    Configuring a Description of the Interface (Optional) 259

    Configuring Frame Relay Using Subinterfaces 259

Verifying Frame Relay 260

Troubleshooting Frame Relay 260

Configuration Examples: Frame Relay 260

Part X Network Security 267

Chapter 28 IP Access Control List Security 269

Access List Numbers 269

Using Wildcard Masks 270

ACL Keywords 270

Creating Standard ACLs 271

Applying Standard ACLs to an Interface 272

Verifying ACLs 273

Removing ACLs 273

Creating Extended ACLs 273

Applying Extended ACLs to an Interface 275

The established Keyword (Optional) 275

Creating Named ACLs 276

Using Sequence Numbers in Named ACLs 276

Removing Specific Lines in Named ACLs Using Sequence Numbers 277

Sequence Number Tips 278

Including Comments About Entries in ACLs 278

Restricting Virtual Terminal Access 279

Configuration Examples: ACLs 279


Chapter 29 Security Device Manager 283

Security Device Manager: Connecting with CLI 283

Security Device Manager: Connecting with GUI 285

SDM Express Wizard with No CLI Preconfiguration 287

Resetting the Router to Factory Defaults Using SDM 297

SDM User Interfaces 298

    Configuring Interfaces Using SDM 298

    Configuring Routing Using SDM 302

SDM Monitor Mode 304

Using SDM to Configure a Router to Act as a DHCP Server 305

Using SDM to Configure an Interface as a DHCP Client 307

Using SDM to Configure NAT/PAT 312

What to Do If You Lose SDM Connectivity Because of an erase startup-config Command 314

Part XI Appendixes 315

Appendix A Binary/Hex/Decimal Conversion Chart 317

Appendix B Create Your Own Journal Here 329


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