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CCNP® Complete Study Guide Wade Edwards, et al SYBEX® CCNP® Complete Study Guide Wade Edwards, CCIE, Terry Jack, CCIE, Todd Lammle, CCNP, Robert Padjen, CCNP, Arthur Pfund, CCIE, Toby Skandier, CCNP, Carl Timm, CCIE San Francisco • London Associate Publisher: Neil Edde Acquisitions and Developmental Editor: Maureen Adams Production Editor: Mae Lum Technical Editor: Craig Vazquez Copyeditor: Sarah Lemaire Compositor: Craig J Woods, Happenstance Type-O-Rama Graphic Illustrator: Happenstance Type-O-Rama CD Coordinator: Dan Mummert CD Technician: Kevin Ly Proofreaders: Jim Brook, Candace English, Jennifer Larsen, Nancy Riddiough Indexer: Nancy Guenther Book Designers: Bill Gibson, Judy Fung Cover Designer: Archer Design Cover Illustrator/Photographer: Photodisc and Victor Arre Copyright © 2005 SYBEX Inc., 1151 Marina Village Parkway, Alameda, CA 94501 World rights reserved No part of this publication may be stored in a retrieval system, transmitted, or reproduced in any way, including but not limited to photocopy, photograph, magnetic, or other record, without the prior agreement and written permission of the publisher Portions of this book were published under the titles: CCNP: Building Scalable Cisco Internetworks Study Guide © 2004 SYBEX Inc., CCNP: Building Cisco Multilayer Switched Networks Study Guide © 2004 SYBEX Inc., CCNP: Building Cisco Remote Access Networks Study Guide © 2004 SYBEX Inc., and CCNP: Cisco Internetwork Troubleshooting Study Guide © 2004 SYBEX Inc Library of Congress Card Number: 2005920775 ISBN: 0-7821-4421-7 SYBEX and the SYBEX logo are either registered trademarks or trademarks of SYBEX Inc in the United States and/or other countries Screen reproductions produced with FullShot 99 FullShot 99 © 1991-1999 Inbit Incorporated All rights reserved FullShot is a trademark of Inbit Incorporated The CD interface was created using Macromedia Director, COPYRIGHT 1994, 1997-1999 Macromedia Inc For more information on Macromedia and Macromedia Director, visit http://www.macromedia.com This study guide and/or material is not sponsored by, endorsed by or affiliated with Cisco Systems, Inc Cisco®, Cisco Systems®, CCDA™, CCNA™, CCDP™, CCSP™, CCIP™, BSCI™, CCNP™, CCIE™, CCSI™, the Cisco Systems logo and the CCIE logo are trademarks or registered trademarks of Cisco Systems, Inc in the United States and certain other countries All other trademarks are trademarks of their respective owners TRADEMARKS: SYBEX has attempted throughout this book to distinguish proprietary trademarks from descriptive terms by following the capitalization style used by the manufacturer The author and publisher have made their best efforts to prepare this book, and the content is based upon final release software whenever possible Portions of the manuscript may be based upon pre-release versions supplied by software manufacturer(s) The author and the publisher make no representation or warranties of any kind with regard to the completeness or accuracy of the contents herein and accept no liability of any kind including but not limited to performance, merchantability, fitness for any particular purpose, or any losses or damages of any kind caused or alleged to be caused directly or indirectly from this book Manufactured in the United States of America 10 To Our Valued Readers: Thank you for looking to Sybex for your CCNP exam prep needs Cisco developed the CCNP certification to validate expertise in implementing and managing Cisco internetworking solutions, and it is currently one of the most highly sought after IT certifications Just as Cisco is committed to establishing measurable standards for certifying those professionals who work in the field of internetworking, Sybex is committed to providing those professionals with the information they need to excel We at Sybex are proud of our reputation for providing certification candidates with the practical knowledge and skills needed to succeed in the highly competitive IT marketplace This four-in-one CCNP Complete Study Guide reflects our commitment to provide CCNP candidates with the most up-to-date, accurate, and economical instructional material on the market The authors and the editors have worked hard to ensure that the book you hold in your hands is comprehensive, in-depth, and pedagogically sound We’re confident that this book will exceed the demanding standards of the certification marketplace and help you, the CCNP certification candidate, succeed in your endeavors As always, your feedback is important to us If you believe you’ve identified an error in the book, please send a detailed e-mail to support@sybex.com And if you have general comments or suggestions, feel free to drop me a line directly at nedde@sybex.com At Sybex, we’re continually striving to meet the needs of individuals preparing for certification exams Good luck in pursuit of your CCNP certification! Neil Edde Publisher—Certification Sybex, Inc Software License Agreement: Terms and Conditions The media and/or any online materials accompanying this book that are available now or in the future contain programs and/or text files (the “Software”) to be used in connection with the book SYBEX hereby grants to you a license to use the Software, subject to the terms that follow Your purchase, acceptance, or use of the Software will constitute your acceptance of such terms The Software compilation is the property of SYBEX unless otherwise indicated and is protected by copyright to SYBEX or other copyright owner(s) as indicated in the media files (the “Owner(s)”) You are hereby granted a single-user license to use the Software for your personal, noncommercial use only You may not reproduce, sell, distribute, publish, circulate, or commercially exploit the Software, or any portion thereof, without the written consent of SYBEX and the specific copyright owner(s) of any component software included on this media In the event that the Software or components include specific license requirements or end-user agreements, statements of condition, disclaimers, limitations or warranties (“End-User License”), those End-User Licenses supersede the terms and conditions herein as to that particular Software component Your purchase, acceptance, or use of the Software will constitute your acceptance of such End-User Licenses By purchase, use or acceptance of the Software you further agree to comply with all export laws and regulations of the United States as such laws and regulations may exist from time to time Software Support Components of the supplemental Software and any offers associated with them may be supported by the specific Owner(s) of that material, but they are not supported by SYBEX Information regarding any available support may be obtained from the Owner(s) using the information provided in the appropriate read.me files or listed elsewhere on the media Should the 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period, you can obtain replacement media of identical format by sending us the defective disk, proof of purchase, and a check or money order for $10, payable to SYBEX Disclaimer SYBEX makes no warranty or representation, either expressed or implied, with respect to the Software or its contents, quality, performance, merchantability, or fitness for a particular purpose In no event will SYBEX, its distributors, or dealers be liable to you or any other party for direct, indirect, special, incidental, consequential, or other damages arising out of the use of or inability to use the Software or its contents even if advised of the possibility of such damage In the event that the Software includes an online update feature, SYBEX further disclaims any obligation to provide this feature for any specific duration other than the initial posting The exclusion of implied warranties is not permitted by some states Therefore, the above exclusion may not apply to you This warranty provides you with specific legal rights; there may be other rights that you may have that vary from state to state The pricing of the book with the Software by SYBEX reflects the allocation of risk and limitations on liability contained in this agreement of Terms and Conditions Shareware Distribution This Software may contain various programs that are distributed as shareware Copyright laws apply to both shareware and ordinary commercial software, and the copyright Owner(s) retains all rights If you try a shareware program and continue using it, you are expected to register it Individual programs differ on details of trial periods, registration, and payment Please observe the requirements stated in appropriate files Copy Protection The Software in whole or in part may or may not be copy-protected or encrypted However, in all cases, reselling or redistributing these files without authorization is expressly forbidden except as specifically provided for by the Owner(s) therein Acknowledgments We would like to thank Neil Edde and Maureen Adams for giving us the opportunity to update this Study Guide We would also like to take a moment to thank everyone else involved in the creation of this book, including Production Editor Mae Lum; Technical Editor Craig Vazquez; Copyeditor Sarah Lemaire; Proofreaders Jim Brook, Candace English, Jennifer Larsen, and Nancy Riddiough; Indexer Nancy Guenther; and Dan Mummert and Kevin Ly of the CD group Contents at a Glance Introduction xxix Part I Building Scalable Cisco Internetworks (BSCI) Chapter Routing Principles Chapter IP Addressing 37 Chapter Network Address Translation 75 Chapter IGRP and EIGRP 99 Chapter OSPF Operation in a Single Area 141 Chapter Interconnecting OSPF Areas 175 Chapter Integrated IS-IS 205 Chapter Border Gateway Protocol 235 Chapter Advanced Border Gateway Protocol 283 Chapter 10 Route Optimization 323 Chapter 11 Design Considerations 357 Part II Building Cisco Multilayer Switched Networks (BCMSN) 377 Chapter 12 The Campus Network 379 Chapter 13 Connecting the Switch Block 413 Chapter 14 VLANs, Trunks, and VTP 445 Chapter 15 Layer Switching and the Spanning Tree Protocol (STP) 481 Chapter 16 Using Spanning Tree with VLANs 501 Chapter 17 Inter-VLAN Routing 537 Chapter 18 Multilayer Switching (MLS) 553 Chapter 19 Understanding and Configuring Multicast Operation 585 Chapter 20 Quality of Service (QoS) 637 Chapter 21 Catalyst Switch Technologies 677 Contents at a Glance Part III Building Cisco Remote Access Networks (BCRAN) vii 703 Chapter 22 Cisco Solutions for Remote Access 705 Chapter 23 Asynchronous Connections 745 Chapter 24 Point-to-Point Protocol 763 Chapter 25 Using Microsoft Win-dows 95/98/2000/XP 797 Chapter 26 Integrated Services Digital Network (ISDN) 815 Chapter 27 Remote Access with Digital Subscriber Line 865 Chapter 28 Remote Access with Cable Modems and Virtual Private Networks 877 Chapter 29 Frame Relay 887 Chapter 30 Queuing and Compression 915 Chapter 31 Network Address Translation and Port Address Translation 941 Chapter 32 Centralized Security in Remote Access Networks 967 Part IV Cisco Internetwork Troubleshooting (CIT) Chapter 33 Troubleshooting Methodology Chapter 34 Network Documentation 1001 Chapter 35 End-System Documentation and Troubleshooting 1023 Chapter 36 Protocol Attributes 1053 Chapter 37 Cisco Diagnostic Commands and TCP/IP Troubleshooting 1081 Chapter 38 TCP/IP Routing Protocol Troubleshooting 1137 Chapter 39 Troubleshooting Serial Line and Frame Relay Connectivity 1177 Chapter 40 Troubleshooting ISDN 1203 Chapter 41 Troubleshooting Switched Ethernet 1235 Chapter 42 Applying Cisco’s Diagnostic Tools 1283 Index 985 987 1327 Contents Introduction xxix Part I Chapter Chapter Chapter Building Scalable Cisco Internetworks (BSCI) Routing Principles Components of Routing Data Routing Tables Populating the Routing Table Reaching the Destination Convergence RIP Convergence IGRP Convergence EIGRP Convergence Link-State Convergence Verifying and Testing a Route Verifying Routes Testing and Troubleshooting Routes Summary Exam Essentials 20 23 23 25 27 28 29 29 30 34 34 IP Addressing 37 Review of IPv4 Addressing IP Terminology The Hierarchical IP Addressing Scheme Extending IP Addresses Variable-Length Subnet Masks Classless Interdomain Routing Route Summarization Decimal-to-Binary Conversion Chart An Overview of IPv6 Addressing IPv6 Address Format IPv6 Address Types Summary Exam Essentials 38 39 40 45 46 54 56 66 66 67 68 73 73 Network Address Translation 75 Understanding Network Address Translation NAT Terminology NAT Operations Configuring NAT Configuring Static NAT 76 77 82 88 89 Contents Chapter Configuring Dynamic NAT Configuring NAT Using Overloading Configuring TCP Load Distribution Configuring NAT for Overlapping Addresses Verifying and Troubleshooting the NAT Configuration Summary Exam Essentials 91 92 93 94 95 97 98 IGRP and EIGRP 99 Scalability Features of Routing Protocols Distance-Vector Protocol Scalability Issues Scalability Limitations of Link-State Routing Protocols Interior Gateway Routing Protocol IGRP Features and Operation IGRP Configuration Verifying and Troubleshooting IGRP Enhanced Interior Gateway Routing Protocol Route Tagging Neighbor Relationships Route Calculation EIGRP Metrics Redistribution for EIGRP Configuring EIGRP Verifying and Troubleshooting EIGRP Summary Exam Essentials Chapter ix OSPF Operation in a Single Area Open Shortest Path First OSPF Terminology OSPF Operation NBMA Overview NBMA Environments Broadcast Non-Broadcast Point-to-Point Point-to-Multipoint Configuring OSPF Discovering the Network with OSPF Configuring OSPF—Single Area Configuring OSPF—Single Area (NBMA Environment) Verifying OSPF Configuration Summary Exam Essentials 100 101 102 102 103 111 114 118 119 119 120 125 128 128 133 139 140 141 142 143 145 155 155 156 157 158 158 159 159 163 166 170 173 174 scaling backbones for campus network – set ip pat on command of Spanning Tree Protocol (STP), 505–519 port cost, 510–513 port priority, 513–517 root configuration, 506–510 timers, 517–519 of VLANs, 448 scaling backbones for campus network layer 2, 404–405 layer 3, 406 scope of problem, 994 scripts for dial-up networking, 809 SDH (Synchronous Digital Hierarchy), 674, 819 SDLC (Synchronous Data Link Control), 1065–1067 secondary bridges in STP, 506 secondary command, 837 secondary nodes in SDLC, 1066 Secure Blueprint for Enterprise Networks, 407 Secure Sockets Layer (SSL), 726, 886 security Cisco access control solutions, 969–970 for DSL, 713 router access modes, 972–974 character-mode connections, 972–973 packet-mode connections, 973–974 terminology, 968–969 virtual profiles, 982–983 with VLANs, 448 and WAN protocol selection, 725–726 security server, 969, 970 segmentation, 416 selector byte (SEL), in NSAP format, 211 send-community option, in peer group update policy, 312 sequence number PDUs (SNPs), 213, 216 sequenced data transfer, 1058, 1059 Serial command, 837 serial interface, output from, 1096–1097 Serial Line Internet Protocol (SLIP), 718 serial lines, troubleshooting, 1178–1193 CSU/DSU loopback tests, 1189, 1189–1190 1367 debug serial interface command, 1187–1189 HDLC encapsulation, 1179–1180 show buffers command, 1186–1187 show controllers command, 1184–1185 show interface serial command, 1180–1184 summary, 1190–1193 serialization delay, 645 server for security, 969 specifying for Windows dial-up networking, 804 server farms, 391 Server Load Balancing (SLB) protocol, 669–670 server mode for VTP domain, 467 Server module in SAFE architecture, 409 Gigabit Ethernet for, 421 service access point identifier field, in LAPD frame, 826, 1214 Service Advertising Protocol (SAP), broadcast problems from misconfiguration, 383 service dhcp command, 772 service packs, for Windows 95/98, 800 service profile identifier (SPID), 819, 1205–1206 service timestamps debug datetime command, 1225 session command, 1273 Session layer in OSI model, 1055 Set Asynchronous Balanced Mode Extended (SABME) message, 829, 830, 1214 set based operating system, 423 set cgmp enable command, 632 set cgmp leave enable command, 632 set command, for route map, 256, 307, 327 set community additive command, 310 set community none command, 310 set enablepass command, 427 set igmp enable command, 633 set interface command, 430–431 set ip pat on command, 961 1368 set ip pat porthandler command – show interface command set ip pat porthandler command, 961 set ip route command, 548 set mls agingtime fast command, 573 set mls enable command, 571 set mls flow command, 572 set mls include command, 571 set password command, 427 set peer command, for IPSec, 884 set port channel command, 520–521 set port duplex command, 436 set port name command, 435 set port speed command, 436 set qos enable command, 657 set qos map command, 657 set spantree backbonefast command, 532 set spantree command, 496, 507 set spantree portcost command, 511 set spantree portfast command, 528 set spantree portpri command, 513–514 set spantree portvlanpri command, 514–515 set spantree priority command, 509 set spantree root command, 507–508 set spantree root secondary command, 507–508 set spantree uplinkfast command, 530 set system modem enable command, 431 set transform-set command, for IPSec, 884 set trunk command, 461–462 set vlan command, 453 set vtp domain command, 472 set vtp pruneeligible command, 475 set vtp v2 enable command, 471 SETUP, 833 shared memory, 679 shared memory switching fabric, 681, 681 shared trees, 605, 607, 607–608 Shiva Password Authentication Protocol (SPAP), 806 Shortest Path First (SPF) trees, 154 viewing information, 230–231 shortest path tree (SPT), 607 show access-lists command, 1090–1091 show arp command, 1127 show buffers command, 685, 1186–1189 show cam command, 695, 1256, 1259–1260 show cdp command, 1245–1248 show cdp neighbors command, 1017, 1019–1020 show cgmp statistics command, 632–633 show clns interface command, 214, 228–229 show clns is-neighbors command, 229–230 show clns protocol command, 228 show commands, 1082–1105 for documentation creation, 1006 for Frame Relay troubleshooting, 1194–1198 frequently used, 1083–1084 for hybrid mode Catalyst CLI, 1238–1240 for troubleshooting BGP, 1162, 1163 EIGRP, 1151 IGRP, 1145 OSPF, 1157–1158 RIP, 1143 show compress command, 937–938 show config command, 1248–1254 show controller bri command, 1221–1222 show controllers command, 1184–1185 show dialer command, 848, 854, 1223–1224 show etherchannel command, 524–525 show flash command, 690 show frame-relay lmi command, 904–905, 1196 show frame-relay map command, 904, 1197–1198 show frame-relay pvc command, 903–904, 1196–1197 show frame-relay route command, 908 show help command, 698–699 show int atm0 command, 874 show interface bri command, 1221 show interface command, 106, 430–431, 434, 1007–1008, 1195–1196, 1245, 1292 for Frame Relay, 902–903 show interface ethernet command – show process cpu command for ftp troubleshooting, 1302 for switch configuration data, 1012 show interface ethernet command, 1287–1288 show interface gigabit command, 542 show interface port-channel command, 542 show interface serial command, 1179, 1180–1184 show ip access-list command, 1100 show ip arp command, 1101 show ip bgp command, 274 show ip bgp neighbors command, 275–276 show ip bgp summary command, 274–275 show ip eigrp events command, 139, 1153 show ip eigrp interfaces command, 135 show ip eigrp neighbor command, 136, 1152 show ip eigrp topology command, 134, 1152 show ip eigrp traffic command, 138–139, 1153 show ip interface command, 582, 1007, 1131–1132 information for documentation, 1008–1009 show ip mroute command, 622 show ip nat statistics command, 96, 958 show ip nat translations command, 91, 95, 957–958 show ip nat translations verbose command, 958 show ip ospf border-routers command, 170, 171–172, 197 show ip ospf command, 170, 171, 198–199 show ip ospf database command, 170, 172, 197 show ip ospf interface command, 170, 172–173, 199–200 show ip ospf neighbor command, 149, 170, 173, 200 show ip ospf neighbor detail command, 200–201 show ip ospf process-id command, 170 show ip pat command, 963 1369 show ip policy command, 334 show ip protocols command, 105–106, 115–116, 135, 1101 information for documentation, 1008 show ip route bgp command, 239 show ip route command, 5–6, 29–30, 547–548, 848, 1101–1102 for BGP, 273–274 for default gateway check, 1139–1140 for EIGRP, 131, 133 for ftp troubleshooting, 1301 for IGRP, 114–115 for IS-IS, 225–226 for OSPF, 196, 197 for static vs dynamic routes, 1141 show ip route eigrp command, 1152, 1165–1166 show ip route ospf command, 196–197 show ip traffic command, 1103–1105 show isdn active command, 848 show isdn status command, 848, 849–850, 853, 1222–1223 show isis database command, 226–228 show isis spf-log command, 230–231 show line command, 812 show log command, 1243–1244 show logging buffer command, 1245 show mac-address-table command, 690 show mac command, 1256–1258 show memory command, 1091 show mls command, 559 show mls entry command, 572, 574 show mls ip command, 573–574 show mls rp command, 568–569 show mls rp interface command, 568 show mls rp vtp-domain command, 568 show modemcap command, 754–755 show multicast group cgmp command, 633 show path command, in NAT, 958 show port capabilities command, 521 show port channel command, 523, 525 show port command, for switch configuration data, 1012–1013 show port commands, 1242–1243 show ppp multilink command, 847, 1224 show process cpu command, 783 1370 show processes command – spanning tree algorithm show processes command, 699 show qos info config command, 658 show queue command, 920, 921 show queueing command, 920–921 show queueing custom command, 931 show queueing priority command, 924–925 show route-map command, 334–335 show running-config command, 163–166, 429, 439–440, 544, 547, 549–550, 1086–1087 for CGMP, 632 for Frame Relay switch, 908–909 on MSFC, 1273–1274 show spanning-tree command, 497, 510, 514 to view port priorities, 512 show spanning-tree uplinkfast command, 531 show spantree command, 498–499, 508–509, 515, 1014, 1260, 1264 show spantree uplinkfast command, 530 show stack command, 1089–1090 show standby command, 668 show startup-config command, 440, 1086–1087 show system command, 1241 show tcam command, 692–693 show tech-support command, 1090 show test command, 1254–1256 show-timezone localtime command, 1225 show trunk command, 464, 477, 523, 1013 show version command, 689–690, 1085–1086, 1261, 1304 3550 Cisco switch response, 692 4000 series response, 694–695 for switch configuration data, 1011–1012 show vlan command, 454, 456–457 show vlans command, 1276 show vtp counters command, 474–475 show vtp domain command, 473, 565–566, 1258 show vtp statistics command, 473 shutdown command, 25 Simple Network Management Protocol (SNMP) 700 Cisco series router support for, 737 and unnumbered interfaces, 65 simple translation entry, 944 single-homed autonomous system, 257 single point of failure, 287, 316–317, 663 single service provider, for multi-homing, 316–317 site-local unicast address (IPv6), 69–70, 70 SLAs See summary link advertisements (SLAs) SLB (Server Load Balancing) protocol, 669–670 sleeptime, for triggered update, 105 SLIP (Serial Line Internet Protocol), 718 SLIP: Unix Connection server type, for Windows dial-up networking, 805 small offices/home offices (SOHOs), 817 Cisco DSL routers, 871 SNAP (Subnetwork Access Protocol), 790 snapshot routing, 700 Cisco series router support for, 737 sniffers, 959 SNPA (subnetwork point of attachment), 208 SNPs (sequence number PDUs), 213, 216 soft-reconfiguration option, in peer group update policy, 312 software displaying versions, 1085–1086 for switches, 686–688 SOHOs See small offices/home offices (SOHOs) SONET (Synchronous Optical Networks), 674, 819 source-based policies, 329, 329–330 Source-Destination-IP, for flow mask configuration, 571 source-interface command, 1115 source-specific multicasting (SSM), 619 source trees, 605–607, 606 spam, 589 SPAN (Switched Port Analyzer), 499, 1262, 1272–1273 spanning tree algorithm, 488 spanning-tree cost interface command – statistical time division multiplexing spanning-tree cost interface command, 511 spanning tree loop, detecting, 496 spanning-tree portfast interface command, 528 Spanning Tree Protocol (STP), 362, 403, 487–494, 1262–1264 configuring, 496–499 convergence, 493 displaying status information, 1260 exam essentials, 499–500, 534–535 example, 493–494, 494 layer bridge use of, 405 and multicast, 604 port states, 492–493 redundant links, 519–534 BackboneFast, 532–533 load balancing, 526–527 parallel Fast EtherChannel links, 520–526 Port Aggregation Protocol (PAgP), 526 PortFast, 527–529 Rapid Spanning Tree Protocol (RSTP), 533–534 UplinkFast, 529–531 scalability, 505–519 port cost, 510–513 port priority, 513–517 root configuration, 506–510 root determination, 506 timers, 517–519 selecting best path, 488–491 root bridge, 489–490 root port, 490–491 selecting designated port, 491–492 troubleshooting, 1263–1264 spanning-tree uplinkfast command, 531 spanning-tree vlan command, 497, 518–519 spanning-tree vlan port priority command, 515–516 SPAP (Shiva Password Authentication Protocol), 806 sparse mode for Protocol Independent Multicast (PIM), 613 routing protocols, 615–619 1371 speed command, 759 SPF (Shortest Path First) trees, 154, 607 algorithm, 142, 217–218 tree calculation in OSPF, 154–155 viewing information, 230–231 SPID (service profile identifier), 819, 1205–1206 split DNS, 81 split horizon and Frame Relay, 899–900, 900 with poison reverse, in distance-vector routing protocols, 12–13 splitterless DSL, 869 spoke interface, 843 spreadsheet, for hardware information, 1004–1005 SSL (Secure Sockets Layer), 726, 886 SSM (source-specific multicasting), 619 Stac compression, 783, 936 stack, displaying information, 1089–1090 standard 8-octet NSAP format, 211, 212 standard access lists, troubleshooting, 1130, 1130–1132 Standard Image IOS, for 2950 series switch, 687 standby ip command, 666 standby preempt command, 667 standby track command, 667 startup configuration, vs running configuration, 1087 stateful backup mode, for SLB, 670 static addressing, 769 static mappings, in Frame Relay, 892–893, 893 static NAT, 80, 945 configuring, 89–91, 953 static routes, 1141 for ISDN, 844 static VLANs, 452 configuring, 452–457 on Catalyst 2950 and 3550 series, 453–457 on Catalyst 4000 series, 453 statically defined routes, 7–8 statistical time division multiplexing (Stat-TDM), 891 1372 stopbits command – switched Ethernet stopbits command, 760 store-and-forward switching method, 494, 495 STP See Spanning Tree Protocol (STP) straight-through cable, 424 StrataCom, 889 streaming transport, 644 stub area, 181, 182, 1156 configuring, 184–187, 185 OSPF, 186–187 design issues, 370 stub autonomous system, 257, 257 stuck in active, 1153 subinterface configuring, 543 in Frame Relay, 900, 900–901 subnet address, 39 subnet mask, 45 for default route configuration, hosts supported by, 48 variable-length, 46–54, 47 See also variable-length subnet masking (VLSM) subnets keyword, for redistribution in OSPF, 341–342 subnetting, 45 Subnetwork Access Protocol (SNAP), 790 subnetwork point of attachment (SNPA), 208 subscribed hosts, for multicast communication, 589 subset VTP advertisements, 468, 468, 469 successor route, 121–122 summary-address command for IS-IS, 355 for OSPF, 354 summary advertisements, 468, 468, 469 summary link advertisements (SLAs), 180 supernetting, 46 supervisory frame in SDLC, 1067 SVCs (switched virtual circuits), 710, 890–891 switch block cabling, 424–426 for campus network, 401 scaling, 450–457 member assignment, 452 VLAN boundaries definition, 451 switch fabric, 448, 457, 680–682 switched Ethernet, 416 cabling issues, 1269–1271 crossover cable, 1271 multimeters and cable testers, 1270 time domain reflectometers (TDRs), 1271 Catalyst troubleshooting tools, 1238–1262 command-line interface, 1238 hybrid mode Catalyst CLI, 1238–1240 RMON (Remote Monitoring), 1261–1262 show cam command, 1259–1260 show cdp command, 1245–1248 show config command, 1248–1254 show interface command, 1245 show log command, 1243–1244 show logging buffer command, 1245 show mac command, 1256–1258 show port commands, 1242–1243 show spantree command, 1260 show system command, 1241 show test command, 1254–1256 show version command, 1261 show vtp domain command, 1258 exam essentials, 1281 hybrid/native command conversion, 1279–1280 Spanning Tree Protocol (STP), 1262–1264 See also Spanning Tree Protocol (STP) troubleshooting connections, 1272–1278 Multilayer Switch Feature Card (MSFC), 1273–1274 switched port analyzer, 1272–1273 virtual LANs, 1265–1268 802.Q trunking, 1268 across routers and switches, 1275–1277 design issues and troubleshooting, 1277–1278 Switched Port Analyzer (SPAN) – TACACS+ Inter-Switch Link Protocol (ISL), 1265–1267 VLAN Trunk Protocol (VTP), 1268 Switched Port Analyzer (SPAN), 499, 1262, 1272–1273 switched virtual circuits (SVCs), 710, 890–891 switches See also specific series numbers at beginning of index architecture and components, 679–682 non-blocking switches, 679–680, 680 switch fabric, 680–682 vs bridges, 482–483, 1237, 1262 Cisco Cluster Management Suite (CMS), 697 current range, 688–696 2950 Cisco switch, 689–691 3550 Cisco switch, 691–693 4000 Cisco switch, 693–695 6500 series Cisco switches, 695–696 debugging, 697–698 disabling MLS, 562–564 displaying status information, 1254–1256 displaying summary information, 1241 exam essentials, 700–701 host name, 429–430 vs hubs, 1237 interface descriptions, 434–436 interfaces, 432–434 IP information on, 430–432 for ISDN, troubleshooting, 1217–1218 LAN segmentation using, 416 memory, 683–686 “metro” interfaces, 673 network configuration table, 1009–1014, 1010 password, 427–429 port speed and duplex, 436–437 Quality of service configuration, 653–658 saving and erasing configuration, 439–441 software, 686–688 system testing, 698–699 troubleshooting, 438–439 1373 verifying connectivity, 437–439 VLANs across routers with, 1275–1277 switching fabric, 679 switching process, 388–394, 678–688 in Frame Relay, 906–909 Layer switching, 391 Layer switching, 392–393 Layer switching, 393 modes, 494–496, 495 multilayer switching, 393–394 OSI model, 388–390 routing, 391–392 switchport access vlan command, 455 switchport mode access command, 455 switchport trunk allowed vlan remove command, 463 switchport trunk pruning vlan remove command, 476 symmetric DSL, 713, 869 symptoms, gathering when troubleshooting, 992–994 synchronization, in BGP, 256–258, 258 synchronous connections, 747 Synchronous Data Link Control (SDLC), 1065–1067 Synchronous Digital Hierarchy (SDH), 674, 819 Synchronous Optical Networks (SONET), 674, 819 System accounting type, 981 system ID, in NSAP format, 211 System LED, on 3600 router, 740 system memory, information about, 1099 system route, in IGRP, 103 T T-1, 711, 817 T reference point, 1212 in ISDN, 824 TAC (Technical Assistance Center), 1324 TACACS+ (Enhanced Terminal Access Controller Access Control System), 722, 969 configuration file, 977–979 1374 tacacs-server command – topology database tacacs-server command, 976 tacacs-server host command, 975 tacacs-server key command, 975 TCAM (ternary content addressable memory), 683 TCP header compression, 784 TCP/IP Properties dialog box (Windows 95/98), IP Address tab, 771 TCP/IP Settings dialog box (Windows 95/ 98), 770, 770 TCP/IP (Transmission Control Protocol/ Internet Protocol) commands for troubleshooting, 1099–1105 show ip access-list command, 1100 show ip arp command, 1101 show ip protocols command, 1101 show ip route command, 1101–1102 show ip traffic command, 1103–1105 TCP load distribution, 85–87, 86, 945, 950–951, 951 configuring, 93–94 TCP (Transmission Control Protocol), 1061, 1077–1078 for BGP, 236 connection sequence, 643 sample connection, 1128–1129, 1129 TDM (time division multiplexing), 748, 817, 891 TDRs (time domain reflectometers), 1271 Technical Assistance Center (TAC), 1324 telecommuters, 710 WAN connection for, 735–738 televisions, filter for cable modem use, 878 Telnet utility, 437–438, 1029–1030 for ISDN, 848 troubleshooting, 1313–1317 templates, in documentation, 1016 Temporal Key Integrity Protocol (TKIP), 715 Terminal Access Controller Access Control System (TACACS+), 722, 969 configuration file, 977–979 Terminal adapter (TA), in ISDN, 823 terminal emulation, 424 terminal endpoint identifier (TEI), 1213–1214 LAPD frame field for, 826 Terminal equipment (TEn), in ISDN, 823 terminal monitor command, 1106 terminal windows, launching for dial-up networking, 810, 811 ternary content addressable memory (TCAM), 683 test of adjacency, 663 testing routes, 30–33 show commands for, 698–699 switches, 698–699 Thinnet, 816 three-way handshake in TCP, 1128, 1129 time division multiplexing (TDM), 748, 817, 891 time domain reflectometers (TDRs), 1271 time-to-live (TTL) configuring, 628–629 IP packet field for, 32 for multicast packets, 609–610, 610 traceroute command and, 1120–1121 timeline, in troubleshooting, 994 timeouts, ICMP messages on, 1076 timers default for STP, 492, 493 in distance-vector routing protocols, 11–12 for IGMPv1, 599 for IGRP, 104–105 for RIP, 15 timers basic command, 105 timers option, in peer group update policy, 312 timestamps applying to messages, 1105 for router debug and log output, 1225 TKIP (Temporal Key Integrity Protocol), 715 Token Ring, 381 VTP Protocol version support for, 471 top-down troubleshooting approach, 999 topologies, in SDLC, 1066 topology database, for EIGRP, 1148–1149 topology table – troubleshooting topology table for EIGRP, 125–126 of neighbor, 120 viewing, 134 TOS field (IPv4), 648 Total Path Attributes Length field, in BGP UPDATE message, 243 totally stubby area, 181, 370, 1156 configuring, 187–189, 188 traceroute command, 32–33, 33, 437–438, 1120–1124 EXEC mode privileged, 1123–1124 user, 1121–1122 multicast, 630 for troubleshooting default gateway, 1140 end-system problems, 1038–1039 tracert command, 1300 traffic IP statistics, 1103 marking in QoS, 650 prioritization, 917 traffic shaping in Frame Relay, 909–911 configuring, 910–911 traffic types, NAT support for, 81–82 transceiver, 1320, 1321 transit autonomous system, 256–257, 257 translating inside local addresses, 83, 83–84, 948, 948–949 Transmission Control Protocol/Internet Protocol (TCP/IP) See TCP/IP (Transmission Control Protocol/ Internet Protocol) Transmission Control Protocol (TCP), 1061, 1077–1078 for BGP, 236 connection sequence, 643 sample connection, 1128–1129, 1129 transparent Ethernet, 673–674 transparent switches for VTP domain, 467, 471 transport command, 759 transport input all command, 757 Transport layer in OSI model, 1055 transport mode in IPSec, 882 1375 trie, 580 triggered updates by distance-vector routing protocols, 11 in IGRP, 104 in RIP, 23–24 Triple Data Encryption Standard (3DES), 882 Trivial File Transfer Protocol (TFTP) server, 439 troubleshooting See also documentation of network access lists, 1129–1135 extended access lists, 1132, 1132–1133 named access lists, 1133–1135 standard access lists, 1130, 1130–1132 Bootstrap Protocol (BootP), 1127 Border Gateway Protocol (BGP), 272–280, 1161–1164 debug commands, 1162–1164 debugging information, 276–280 eBGP vs iBGP, 1161–1162 neighbor relationships, 1161 route information, 273–274 show commands, 1162, 1163 typical problems, 1164 viewing neighbor information, 274–276 Cisco model, 990, 990–998 step1: gather symptoms, 992–994 step2: problem isolation, 994–995 step3: problem correction, 995–997 step4: documentation update, 998 data accuracy for, 1181 default gateways, 1138–1140, 1139 digital subscriber line (DSL), 874 Dynamic Host Configuration Protocol (DHCP), 1127 end-system problems, 1035–1049 with arp command, 1040–1041 exam essentials, 1050–1051 with ipconfig command, 1045–1048 with nbtstat command, 1048–1049 with netstat command, 1044–1045 with Ping, 1036–1038 1376 troubleshooting – troubleshooting with route command, 1041–1043 with Traceroute, 1038–1039 Enhanced Interior Gateway Routing Protocol (EIGRP), 133–139, 1146–1153 debug commands, 1151–1152 neighbor formation, 1147–1149 protocol information, 135–136 route information, 133–134 show commands, 1151 typical problems, 1152–1153 viewing neighbor information, 136–137 viewing packets, 137–139 Ethernet, 1312–1323 exam essentials, 1000, 1175, 1325 Frame Relay, 1193–1201 debug commands, 1198–1199 exam essentials, 1202 show commands, 1194–1198 summary, 1200–1201 host connectivity, 1124–1129 optaining IP address, 1124–1127 Interior Gateway Routing Protocol (IGRP), 114–118, 1144–1146 debug commands, 1145–1146 features and operation, 1144–1145 protocol information, 115–116 route information, 114–115 show commands, 1145 typical problems, 1146 viewing route updates, 116–118 Intermediate System to Intermediate System (IS-IS), 225–231 link-state database information, 226–228 route information, 225–226 routing protocol information, 228–229 viewing neighbor information, 229–230 viewing SPF information, 230–231 IP multicast connectivity, 629–631 ISDN, 1218–1224 clear interface bri command, 1219–1220 with ping, 1219 show controller bri command, 1221–1222 show dialer command, 1223–1224 show interface bri command, 1221 show isdn status command, 1222–1223 show ppp multilink command, 1224 by layer, 998–999 modem configuration, 757 and network complexity, 988–989, 989 Open Shortest Path First (OSPF), 196–203, 1153–1160 area types, 1155–1157 debug commands, 1158–1160 link-state database information, 197–198 neighbor and adjacency formation, 1154–1155 neighbor information, 200–202 OSPF packets, 202 routing protocol information, 198–200 routing tables, 196–197 show commands, 1157–1158 typical problems, 1160 Point-to-Point Protocol (PPP), 786–795 debug ppp authentication command, 787, 840, 842, 1206 debug ppp negotiation command, 787–791, 1229–1231 debug ppp packet command, 791–794, 1232 policy-based routing, 333–336, 335 problem identification and resolution ftp connection, 1296–1307 installation configuration of router, 1284–1296 wide area network (WAN), 1307–1312 real world scenario, 997 redistribution of routing protocols, 1165–1170 distribute lists, 1168–1169 metrics, 1165–1168 route maps, 1169–1170 troubleshooting commands – trunk on command routes, 30–33 Routing Information Protocol (RIP), 1142–1144 debug commands, 1143 show commands, 1143 typical problems, 1144 versions and 2, 1143 serial lines, 1178–1193 CSU/DSU loopback tests, 1189, 1189–1190 debug serial interface command, 1187–1189 exam essentials, 1202 HDLC encapsulation, 1179–1180 show buffers command, 1186–1187 show controllers command, 1184–1185 show interface serial command, 1180–1184 summary, 1190–1193 telephone company involvement, 1190–1191 static and dynamic routing, 1141 summary sheet for TCP/IP symptoms and action plans, 1173–1174 symptoms and problems, 1172–1173 switched Ethernet connections, 1272–1278 Multilayer Switch Feature Card (MSFC), 1273–1274 switched port analyzer, 1272–1273 virtual LANs, design issues, 1277–1278 troubleshooting commands, 1082–1124 debug commands, 1105–1112 global, 1108 interface, 1108–1109 IP-related, 1110–1112 limiting output, 1106–1107 protocols, 1109–1110 verifying packet flow without using, 1107 exam essentials, 1136 interface commands, 1091–1098 show interface command, 1093–1097 1377 show ip interface command, 1097–1098 show queue command, 1092–1093 show queueing command, 1092–1093 logging commands, 1112–1114 ping command, 1116–1120 privileged EXEC mode, 1118–1120 user EXEC mode, 1117–1118 process commands, 1098–1099 show processes cpu command, 1098–1099 show processes memory command, 1099 router core dump, 1114–1116 exception command, 1115–1116 write core command, 1116 show commands, 1082–1105 frequently used, 1083–1084 show access-lists command, 1090–1091 show buffers command, 1087–1089 show memory command, 1091 show running-config command, 1086–1087 show stack command, 1089–1090 show startup-config command, 1086–1087 show tech-support command, 1090 show version command, 1085–1086 TCP/IP protocol commands, 1099–1105 show ip access-list command, 1100 show ip arp command, 1101 show ip protocols command, 1101 show ip route command, 1101–1102 show ip traffic command, 1103–1105 traceroute command, 1120–1124 privileged EXEC mode, 1123–1124 user EXEC mode, 1121–1122 trunk links, 458 clearing VLANs from, 463–464 for inter-VLAN routing, 541 verifying, 464–465 trunk on command, 461–462 1378 trunking – Van Jacobson algorithm trunking, 461–465, 522 clearing VLANs from trunk lines, 463–464 configuring ports, 461–463 for 2950 and 3550 series switches, 462–463 for 4000 switch, 461–462 verifying, 523 verifying trunk links, 464–465 trust, 652–653, 656 TTL (time-to-live) configuring, 628–629 IP packet field for, 32 for multicast packets, 609–610, 610 traceroute command and, 1120–1121 tunnel mode in IPSec, 882 tunneling, automatic, 71 type-length-value (TLV), VTP Protocol version support for unrecognized, 471 type of service policies, 331–333, 332 type of traffic policies, 330–331, 331 U U reference point, 1212 in ISDN, 824 UAf, 830, 831 UART (Universal Asynchronous Receiver/ Transmitter), 747 UDP (User Datagram Protocol), 1062, 1078–1079 ip helper-address command and, 1126 undebug all command, 97, 118, 280, 698 Unfeasible Routes Length field, in BGP UPDATE message, 243 unicast, 586, 587–588, 588 unicast address (IPv6), 68–71 global, 69, 69 site-local, 69–70, 70 unicast route table, 605 Unicast Source Address (USA), for CGMP, 601 unicast updates configuring IGRP to send, 112 configuring RIP to allow, 1144 unidirectional shared tree distribution, 607, 608 United States Defense Department, 942 Universal Asynchronous Receiver/ Transmitter (UART), 747 Unix help files (man pages), 1028 network information collection, 1026 unnumbered frame in SDLC, 1067 unreachable route in IGRP, 104 unshielded twisted-pair (UTP) cable, 416 unspecified IPv6 address, 71 unsuppress-map option, in peer group update policy, 312 UPDATE message in BGP, 242, 242–247, 254 in EIGRP, 27, 28 update-source option, in peer group update policy, 312 update timer, for RIP, 15 uplink port on hub, 1271 UplinkFast, 529–531 configuring, 530–531 USA (Unicast Source Address), for CGMP, 601 User Datagram Protocol (UDP), 1062, 1078–1079 ip helper-address command and, 1126 user EXEC mode for ping command, 1117–1118 for router logon, 29 for traceroute command, 1121–1122 username password command, 778, 841, 973 V V reference point, in ISDN, 824 V.35 cable, 729 V.42bis, 752 V.44 compression standard, 752 V.92 standard, 752 VACLs (VLAN access control lists), 360–361 Van Jacobson algorithm, 935 variable-length subnet masking (VLSM) – VLAN Trunk Protocol (VTP) variable-length subnet masking (VLSM), 18, 46–54, 47, 1072–1075 design considerations, 53–54 example with IP addresses, 52 tips for using, 1075–1076 and VLAN design, 539 variance command, 109 variance for route, 109 verbose keyword, for show ip nat translations command, 95 Version field, in BGP OPEN message, 241 version option, in peer group update policy, 312 very-high bit-rate DSL, 713 very-high data rate DSL, 870 video conferencing, ADSL and, 869 virtual circuits, 719, 885 in Frame Relay, 889–891 permanent, 891, 892 switched, 890–891 virtual ip-address command, 670 virtual links in OSPF, 193, 193–194, 194 and stub areas, 181 virtual local area networks (VLANs), 383, 385–386, 386, 446, 1265–1268 802.1Q trunking, 1268 See also 802.1Q standard auxiliary, 477 clearing from trunk links, 463–464 communication between See inter-VLAN routing default switch configuration, 1278 design benefits, 446–450 broadcast control, 447–448 collapsed backbone and, 449, 449–450 flexibility and scalability, 448 security, 448 exam essentials, 478–479 identifying, 458–460 Inter-Switch Link Protocol (ISL), 459–460 Inter-Switch Link Protocol (ISL), 1265–1267 MLS-RP and assignments, 566–567 1379 scaling switch block, 450–457 boundary definition, 451 memberships, 452 static VLAN configuration, 452–457 standards, 502–505 Common Spanning Tree (CST), 504 Multiple Spanning Tree (MST), 505 Per-VLAN spanning tree (PVST), 503–504 Per-VLAN spanning tree+ (PVST+), 504–505 troubleshooting on routers, 1276–1277 viewing configuration, 454 viewing parameters, 509–510 VLAN Trunk Protocol (VTP), 1268 virtual private networks (VPNs), 726, 749, 881–886 exam essentials, 886 IPSec, 881–884 components, 882 configuring, 883–884 virtual profiles, 982–983 Virtual Router Redundancy Protocol (VRRP), 671 virtual server, 669 VLAN See virtual local area networks (VLANs) VLAN access control lists (VACLs), 360–361 vlan database command, 453 VLAN ID (VID), 460 VLAN Tag Protocol Identifier (TPID), 460 VLAN Trunk Protocol (VTP), 465–477, 1268 advertisements, 468, 468–470 client, 1268 configuring, 470–475 domain, 472 verifying, 473–475 version, 470–472 VTP mode, 472–473 displaying information, 1258 pruning, 475–477, 476 server, 465, 1268 transparent mode, 466, 1268 1380 VLSM – Windows name resolution VLSM See variable-length subnet masking (VLSM) voice traffic, allocating VLAN for, 477 VoIP (Voice over IP), auto-QoS for, 652 volt-ohm meters, 1270 volume, of modem speaker, 759 VRRP See Virtual Router Redundancy Protocol (VRRP) VTP See VLAN Trunk Protocol (VTP) VTP domain adding to, 475 assignments, 565–566 configuring, 472 modes of operation, 466–467, 467 password, 466 vtp pruning command, 476 W WAN See wide area network (WAN) websites, automatic connection with dial-up networking, 798 weight option, in peer group update policy, 312 weighted fair queuing (WFQ), 651, 916, 919–921 weighted least connections load sharing, 669 weighted round-robin load sharing, 669 weighted round-robin queuing, 652 Welch, Terry, 752 Well-known discretionary path attribute (BGP), 243 Well-known mandatory path attribute (BGP), 243 WEP (Wired Equivalent Protocol), 715 Western Digital, 415 WFQ See weighted fair queuing (WFQ) WIC ACT LED, on 1600 series router, 741 WIC CD LED, on 1600 series router, 741 wide area network (WAN), 706 cabling and assembling, 729–742 company site equipment, 732–738 central site, 732–733 remote branch, 734–735 for telecommuter, 735–738 connection types, 707–717 asynchronous dial-up, 708, 730 Asynchronous Transfer Mode (ATM), 715 Frame Relay, 710–711, 731 Integrated Services Digital Network (ISDN), 709, 730–731 leased lines, 711–714 summary, 716–717 wireless and cellular, 715–716 X.25, 708 encapsulation protocols, 717–720 selecting, 720–726 growth and static routes, 7–8 hierarchical design, 358, 359 Access layer, 359–360 Core layer, 363 overview, 729–731 troubleshooting connections, 1307–1312 verifying installation, 739–742 at central site, 739–740 at remote branch, 740–741 for telecommuter, 741–742 wildcard mask, 129, 161 window size for network connection, 1058 Windows 95/98/2000/XP dial-up networking client configuration, 800–810, 801 configuring, 799 exam essentials, 813–814 launching terminal windows, 810, 811 locking DTE (data terminal equipment) speed, 810, 811 reasons to use, 798–799 verifying connection, 812, 812 multilink configuration, 785 network information collection, 1026 password encryption, 778 Windows for Workgroups and Windows NT 3.1 server type, for dial-up networking, 805 Windows Internet Name Service (WINS), 1034 Windows name resolution, 1033–1034 winipcfg.exe – Ziv winipcfg.exe, 1032 wire, 49 wire speed switches, 680 Wired Equivalent Protocol (WEP), 715 wireless technologies, 707 for WAN, 715–716 wiring, 750 See also cabling Withdraw Routes field, in BGP UPDATE message, 243 workgroup layer, 397 See also Distribution layer in design model write core command, 1116 wrr-queue bandwidth command, 653 wrr-queue cos-map command, 653 X X.25 protocol, 719 for WAN, 708 xDSL, 866 See also digital subscriber line (DSL) Xerox, 415 XTAGs, 559 Z Ziv, Jacob, 752 1381 ... Internetworks Study Guide © 2004 SYBEX Inc., CCNP: Building Cisco Multilayer Switched Networks Study Guide © 2004 SYBEX Inc., CCNP: Building Cisco Remote Access Networks Study Guide © 2004 SYBEX...CCNP® Complete Study Guide Wade Edwards, CCIE, Terry Jack, CCIE, Todd Lammle, CCNP, Robert Padjen, CCNP, Arthur... skills needed to succeed in the highly competitive IT marketplace This four-in-one CCNP Complete Study Guide reflects our commitment to provide CCNP candidates with the most up-to-date, accurate,

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