Table of Contents
Cisco Switching Black Book...............................................................................................................................	1
Introduction.........................................................................................................................................................	4
Overview..................................................................................................................................................	4
Is This Book for You?..............................................................................................................................	4
How to Use This Book.............................................................................................................................	4
The Black Book Philosophy....................................................................................................................	5
Chapter 1: Network Switching Fundamentals.................................................................................................	6
In Depth...................................................................................................................................................	6
Physical Media and Switching Types......................................................................................................	6
A Bit of History.......................................................................................................................................	7
Networking Architectures.................................................................................................................	7
The Pieces of Technology........................................................................................................................	9
Repeaters.........................................................................................................................................	10
Hubs.................................................................................................................................................	10
Bridges.............................................................................................................................................	11
Routers.............................................................................................................................................	13
Switches...........................................................................................................................................	13
Network Design.....................................................................................................................................	14
Collision Domains...........................................................................................................................	15
Broadcast Domains..........................................................................................................................	16
Why Upgrade to Switches?.............................................................................................................	16
Switched Forwarding......................................................................................................................	19
Switched Network Bottlenecks.......................................................................................................	20
The Rule of the Network Road........................................................................................................	22
Switched Ethernet Innovations..............................................................................................................	23
Full−Duplex Ethernet......................................................................................................................	23
Fast Ethernet....................................................................................................................................	23
Gigabit Ethernet..............................................................................................................................	24
The Cisco IOS........................................................................................................................................	24
Connecting to the Switch................................................................................................................	25
Powering Up the Switch..................................................................................................................	25
The Challenges.......................................................................................................................................	27
Today’s Trend........................................................................................................................................	27
Entering and Exiting Privileged EXEC Mode.......................................................................................	28
Entering and Exiting Global Configuration Mode.................................................................................	28
Entering and Exiting Interface Configuration Mode.............................................................................	28
Entering and Exiting Subinterface Configuration Mode.......................................................................	28
Saving Configuration Changes..............................................................................................................	29
Chapter 2: Basic Switch Configuration..........................................................................................................	30
In Depth.................................................................................................................................................	30
Command−Line Interfaces....................................................................................................................	30
Campus Hierarchical Switching Model.................................................................................................	31
Access Layer...................................................................................................................................	32
Distribution Layer...........................................................................................................................	32
Core Layer.......................................................................................................................................	33
Remote Network Monitoring.................................................................................................................	33
Connecting to the Console Port.............................................................................................................	34
Console Cable Pinouts.....................................................................................................................	35
Console Connectors.........................................................................................................................	36

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Table of Contents
Chapter 2: Basic Switch Configuration
The RJ−45−to−AUX Port Console Connector Pinouts...................................................................	36
Switch IOSs...........................................................................................................................................	38
The IOS Configuration Modes........................................................................................................	38
Limiting Telnet Access..........................................................................................................................	39
Implementing Privilege Levels..............................................................................................................	39
Configuring an IOS−Based CLI Switch................................................................................................	39
Setting the Login Passwords...........................................................................................................	40
Setting Privilege Levels...................................................................................................................	40
Assigning Allowable Commands....................................................................................................	40
Setting the Console Port Time−out Value.......................................................................................	40
Configuring the Telnet Time−out Value.........................................................................................	41
Configuring the Hostname..............................................................................................................	41
Configuring the Date and Time.......................................................................................................	41
Configuring an IP Address and Netmask........................................................................................	41
Configuring a Default Route and Gateway.....................................................................................	41
Configuring Port Speed and Duplex...............................................................................................	42
Enabling SNMP Contact.................................................................................................................	42
Configuring a Set/Clear−Based CLI Switch..........................................................................................	42
Logging On to a Switch...................................................................................................................	42
Setting the Login and Enable Passwords........................................................................................	43
Changing the Console Prompt.........................................................................................................	43
Entering a Contact Name and Location Information......................................................................	44
Configuring System and Time Information....................................................................................	44
Configuring an IP Address and Netmask........................................................................................	44
Configuring a Default Route and Gateway.....................................................................................	45
Viewing the Default Routes............................................................................................................	45
Configuring Port Speed and Duplex...............................................................................................	45
Enabling SNMP...............................................................................................................................	46
Configuring Trap Message Targets.................................................................................................	46
Configuring a Menu−Driven IOS..........................................................................................................	47
Configuring the Console Port..........................................................................................................	48
Configuring Telnet..........................................................................................................................	48
Configuring the Password...............................................................................................................	48
Configuring an IP Address and Default Gateway...........................................................................	48
Configuring SNMP..........................................................................................................................	49
Configuring ROM..................................................................................................................................	50
Entering ROM Configuration Mode...............................................................................................	50
Booting ROM Mode from a Flash Device......................................................................................	50
Configuring SNMP..........................................................................................................................	51
Configuring RMON........................................................................................................................	51
Configuring RMON on a Set/Clear−Based Interface.....................................................................	51
Using Set/Clear Command Set Recall Key Sequences..........................................................................	52
Using IOS−Based Command Editing Keys and Functions...................................................................	52
Chapter 3: WAN Switching.............................................................................................................................	54
In Depth.................................................................................................................................................	54
WAN Transmission Media....................................................................................................................	55
Synchronous Transport Signal (STS)..............................................................................................	56
Cisco WAN Switches............................................................................................................................	57
MGX 8200 Series............................................................................................................................	57
IGX 8400 Series..............................................................................................................................	58

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Table of Contents
Chapter 3: WAN Switching
BPX 8600 Series Wide−Area Switches..........................................................................................	58
MGX 8800 Series Wide−Area Edge Switches...............................................................................	59
WAN Switch Hardware Overview........................................................................................................	59
Cisco WAN Switch Network Topologies..............................................................................................	60
Network Management............................................................................................................................	61
The CLI...........................................................................................................................................	61
WAN Manager................................................................................................................................	61
Accessing and Setting Up IGX and BPX Switches...............................................................................	62
Adding New Users..........................................................................................................................	62
Displaying a User’s Password.........................................................................................................	62
Changing a User’s Password...........................................................................................................	62
Using the History Command...........................................................................................................	63
Displaying a Summary of All Card Modules..................................................................................	63
Displaying Detailed Information for a Card Module......................................................................	63
Displaying the Power and Temperature of a Switch.......................................................................	63
Displaying the ASM Statistics for BPX..........................................................................................	63
Configuring the ASM Setting for BPX...........................................................................................	63
Logging Out....................................................................................................................................	63
Resetting the Switch........................................................................................................................	63
Displaying Other Switches..............................................................................................................	64
Setting the Switch Name.................................................................................................................	64
Setting the Time Zone.....................................................................................................................	64
Configuring the Time and Date.......................................................................................................	64
Configuring the Control and Auxiliary Ports..................................................................................	64
Modifying the Functions of the Control and Auxiliary Ports.........................................................	64
Configuring the Printing Function..................................................................................................	64
Configuring the LAN Interface.......................................................................................................	64
Accessing the MGX 8850 and 8220......................................................................................................	65
Adding New Users..........................................................................................................................	65
Changing Passwords........................................................................................................................	65
Assigning a Switch Hostname.........................................................................................................	65
Displaying a Summary of All Modules...........................................................................................	66
Displaying Detailed Information for the Current Card...................................................................	66
Changing the Time and Date...........................................................................................................	66
Displaying the Configuration of the Maintenance and Control Ports.............................................	66
Displaying the IP Address...............................................................................................................	66
Configuring the IP Interface............................................................................................................	67
Displaying the Alarm Level of the Switch......................................................................................	67
Chapter 4: LAN Switch Architectures............................................................................................................	68
In Depth.................................................................................................................................................	68
The Catalyst Crescendo Architecture....................................................................................................	68
BUS.................................................................................................................................................	68
ASICs..............................................................................................................................................	69
The Crescendo Processors...............................................................................................................	71
Crescendo Logic Units....................................................................................................................	71
Other Cisco Switch Processors, Buses, ASICs, and Logic Units..........................................................	72
CAM................................................................................................................................................	72
AXIS Bus........................................................................................................................................	72
CEF ASIC........................................................................................................................................	73
Phoenix ASIC..................................................................................................................................	75

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Chapter 4: LAN Switch Architectures
LCP..................................................................................................................................................	75
SAGE ASIC....................................................................................................................................	75
QTP ASIC.......................................................................................................................................	75
QMAC.............................................................................................................................................	76
Bridging Types......................................................................................................................................	76
Source Route Bridging....................................................................................................................	76
Source Route Transparent Bridging................................................................................................	77
Source Route Translational Bridging..............................................................................................	77
Transparent Bridging.......................................................................................................................	77
Source Route Switching..................................................................................................................	77
Switching Paths......................................................................................................................................	78
Process Switching............................................................................................................................	78
Fast Switching.................................................................................................................................	78
Autonomous Switching...................................................................................................................	79
Silicon Switching............................................................................................................................	79
Optimum Switching........................................................................................................................	79
Distributed Switching......................................................................................................................	79
NetFlow Switching..........................................................................................................................	79
System Message Logging......................................................................................................................	80
Loading an Image on the Supervisor Engine III....................................................................................	80
Booting the Supervisor Engine III from Flash.......................................................................................	81
Setting the Boot Configuration Register................................................................................................	81
Configuring Cisco Express Forwarding.................................................................................................	81
Enabling CEF..................................................................................................................................	81
Disabling CEF.................................................................................................................................	81
Enabling dCEF................................................................................................................................	82
Disabling dCEF...............................................................................................................................	82
Disabling CEF on an Individual Interface.......................................................................................	82
Configuring CEF Load Balancing...................................................................................................	82
Disabling CEF Load Balancing.......................................................................................................	82
Enabling Network Accounting for CEF..........................................................................................	82
Setting Network Accounting for CEF to Collect Packet Numbers.................................................	82
Viewing Network Accounting for CEF Statistics...........................................................................	82
Viewing CEF Packet−Dropped Statistics.......................................................................................	83
Viewing Non−CEF Path Packets....................................................................................................	83
Disabling Per−Destination Load Sharing..............................................................................................	83
Viewing the Adjacency Table on the 8500 GSR...................................................................................	83
Clearing the Adjacency Table on the 8500 GSR...................................................................................	83
Enabling Console Session Logging on a Set/Clear Command−Based IOS..........................................	83
Enabling Telnet Session Logging on a Set/Clear Command−Based IOS.............................................	84
Disabling Console Session Logging on a Set/Clear Command−Based IOS.........................................	84
Disabling Telnet Session Logging on a Set/Clear Command−Based IOS............................................	84
Setting the System Message Severity Levels on a Set/Clear Command−Based IOS............................	84
Enabling the Logging Time Stamp on a Set/Clear Command−Based Switch......................................	84
Disabling the Logging Time Stamp on a Set/Clear Command−Based Switch.....................................	85
Configuring the Logging Buffer Size on a Set/Clear Command−Based Switch...................................	85
Clearing the Server Logging Table........................................................................................................	85
Disabling Server Logging......................................................................................................................	85
Displaying the Logging Configuration..................................................................................................	86
Displaying System Logging Messages..................................................................................................	86

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Table of Contents
Chapter 5: Virtual Local Area Networks.......................................................................................................	88
In Depth.................................................................................................................................................	88
The Flat Network of Yesterday..............................................................................................................	88
Why Use VLANs?.................................................................................................................................	89
VLAN Basics..................................................................................................................................	90
A Properly Switched Network........................................................................................................	90
Switched Internetwork Security......................................................................................................	91
Scaling with VLANs..............................................................................................................................	92
VLAN Boundaries...........................................................................................................................	92
VLAN Membership Types..............................................................................................................	93
Traffic Patterns Flowing through the Network...............................................................................	93
Cisco’s VLAN Recommendations..................................................................................................	93
VLAN Trunking.....................................................................................................................................	94
Trunk Types....................................................................................................................................	94
LAN Emulation (LANE).................................................................................................................	97
VLAN Trunking Protocol (VTP)...........................................................................................................	97
VTP Versions..................................................................................................................................	98
VTP Advertisements.......................................................................................................................	98
VTP Switch Modes.......................................................................................................................	100
Methods for VLAN Identification.................................................................................................	101
Dynamic Trunking Protocol..........................................................................................................	101
InterVLAN Routing.............................................................................................................................	101
Internal Route Processors..............................................................................................................	102
How InterVLAN Routing Works..................................................................................................	102
Configuring a Static VLAN on a Catalyst 5000 Series Switch...........................................................	103
Configuring Multiple VLANs on a Catalyst 5000 Series Switch........................................................	103
Creating VLANs on a Catalyst 1900EN Series...................................................................................	103
Assigning a Static VLAN to an Interface on a 1900EN Series...........................................................	104
Viewing the VLAN Configuration on a 1900 Series...........................................................................	105
Viewing an Individual VLAN Configuration on a 1900 Series..........................................................	105
Configuring a Trunk Port on a Cisco 5000 Series...............................................................................	105
Mapping VLANs to a Trunk Port........................................................................................................	107
Configuring a Trunk Port on a Cisco 1900EN Series..........................................................................	107
Clearing VLANs from Trunk Links on a Cisco 5000 Series...............................................................	107
Clearing VLANs from Trunk Links on a Cisco 1900EN Series.........................................................	107
Verifying a Trunk Link Configuration on a 5000 Series.....................................................................	108
Verifying a Trunk Link Configuration on a 1900EN Series................................................................	108
Configuring the VTP Version on a Catalyst 5000 Switch...................................................................	108
Configuring a VTP Domain on a Catalyst 1900 Switch......................................................................	109
Setting a VTP Domain Password on a Catalyst Switch.......................................................................	109
Configuring a Catalyst 1900 Switch as a VTP Server.........................................................................	109
Configuring a Catalyst 1900 Switch as a VTP Client.........................................................................	109
Configuring a Catalyst 1900 Switch for Transparent Mode................................................................	109
Configuring VTP Pruning on a Catalyst 1900 Switch.........................................................................	110
Configuring VTP on a Set/Clear CLI Switch......................................................................................	110
Configuring VTP on a 1900 Cisco IOS CLI Switch...........................................................................	110
Verifying the VTP Configuration on a Set/Clear CLI.........................................................................	111
Displaying VTP Statistics....................................................................................................................	111
Configuring VTP Pruning on a Set/Clear CLI Switch........................................................................	112
Disabling Pruning for Unwanted VLANs............................................................................................	112
Configuring IP InterVLAN Routing on an External Cisco Router......................................................	112
Configuring IPX InterVLAN Routing on an External Router.............................................................	113

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Table of Contents
Chapter 6: InterVLAN and Basic Module Configuration..........................................................................	114
In Depth...............................................................................................................................................	114
Internal Route Processors....................................................................................................................	114
Available Route Processors...........................................................................................................	116
Routing Protocol Assignment.......................................................................................................	120
Supervisor Engine Modules.................................................................................................................	120
Supervisor Engines I and II...........................................................................................................	120
Supervisor Engine III....................................................................................................................	121
Using the Supervisor Engine.........................................................................................................	122
Etherport Modules...............................................................................................................................	122
Port Security..................................................................................................................................	123
Manually Configured MAC Addresses.........................................................................................	123
Determining the Slot Number in Which a Module Resides................................................................	123
Accessing the Internal Route Processor from the Switch....................................................................	124
Configuring a Hostname on the RSM..................................................................................................	124
Assigning an IP Address and Encapsulation Type to an Ethernet Interface........................................	125
Setting the Port Speed and Port Name on an Ethernet Interface.........................................................	125
Configuring a Default Gateway on a Catalyst 5000............................................................................	126
Verifying the IP Configuration on a Catalyst 5000.............................................................................	126
Enabling RIP on an RSM.....................................................................................................................	126
Viewing the RSM’s Running Configuration.......................................................................................	127
Configuring InterVLAN Routing on an RSM.....................................................................................	127
Configuring IPX InterVLAN Routing on the RSM.............................................................................	128
Configuring AppleTalk InterVLAN Routing on an RSM...................................................................	128
Viewing the RSM Configuration.........................................................................................................	129
Assigning a MAC Address to a VLAN...............................................................................................	129
Viewing the MAC Addresses..............................................................................................................	129
Configuring Filtering on an Ethernet Interface....................................................................................	130
Configuring Port Security on an Ethernet Module..............................................................................	130
Clearing MAC Addresses....................................................................................................................	131
Configuring the Catalyst 5000 Supervisor Engine Module.................................................................	131
Setting the boot config−register on the Supervisor Engine Module....................................................	132
Changing the Management VLAN on a Supervisor Engine................................................................	133
Viewing the Supervisor Engine Configuration....................................................................................	133
Configuring the Cisco 2621 External Router for ISL Trunking..........................................................	134
Configuring Redundancy Using HSRP...............................................................................................	135
Chapter 7: IP Multicast..................................................................................................................................	137
In Depth...............................................................................................................................................	137
IP Multicasting Overview....................................................................................................................	137
Broadcast.......................................................................................................................................	138
Unicast...........................................................................................................................................	138
Multicast........................................................................................................................................	139
IP Multicasting Addresses...................................................................................................................	140
The Multicast IP Structure............................................................................................................	140
Delivery of Multicast Datagrams..................................................................................................	142
Multicast Distribution Tree...........................................................................................................	142
Multicast Forwarding....................................................................................................................	143
IGMP Protocols.............................................................................................................................	143
Internet Group Management Protocol (IGMP)....................................................................................	145
IGMPv1.........................................................................................................................................	145
IGMPv2.........................................................................................................................................	146

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Table of Contents
Chapter 7: IP Multicast
Time to Live..................................................................................................................................	147
Multicast at Layer 2.............................................................................................................................	147
IGMP Snooping.............................................................................................................................	147
Cisco Group Management Protocol..............................................................................................	148
Router Group Management Protocol............................................................................................	148
GARP Multicast Registration Protocol.........................................................................................	149
Configuring IP Multicast Routing.......................................................................................................	149
Disabling IP Multicast Routing.....................................................................................................	149
Enabling PIM on an Interface.......................................................................................................	149
Disabling PIM on an Interface......................................................................................................	149
Configuring the Rendezvous Point................................................................................................	150
Adding a Router to a Multicast Group.................................................................................................	150
Configuring a Router to Be a Static Multicast Group Member....................................................	150
Restricting Access to a Multicast Group.......................................................................................	150
Changing the IGMP Version...............................................................................................................	150
Changing the IGMP Host−Query Message Interval............................................................................	151
Configuring Multicast Groups.............................................................................................................	151
Removing Multicast Groups................................................................................................................	151
Configuring Multicast Router Ports.....................................................................................................	151
Displaying Multicast Routers........................................................................................................	151
Removing the Multicast Router....................................................................................................	152
Configuring IGMP Snooping...............................................................................................................	152
Disabling IGMP Snooping............................................................................................................	152
Configuring IGMP Fast−Leave Processing.........................................................................................	152
Disabling IGMP Fast−Leave Processing......................................................................................	152
Displaying IGMP Statistics.................................................................................................................	153
Displaying Multicast Routers Learned from IGMP.............................................................................	153
Displaying IGMP Multicast Groups....................................................................................................	153
Configuring CGMP..............................................................................................................................	154
Disabling CGMP...........................................................................................................................	154
Enabling CGMP Fast−Leave Processing......................................................................................	154
Disabling CGMP Fast−Leave Processing.....................................................................................	154
Displaying CGMP Statistics..........................................................................................................	154
Configuring RGMP on the Switch.......................................................................................................	155
Disabling RGMP on the Switch....................................................................................................	155
Configuring RGMP on the Router.......................................................................................................	155
Disabling RGMP on the Router....................................................................................................	155
Displaying RGMP Groups...................................................................................................................	155
Displaying RGMP−Capable Router Ports...........................................................................................	156
Displaying RGMP VLAN Statistics....................................................................................................	156
Configuring GMRP..............................................................................................................................	156
Disabling GMRP...........................................................................................................................	157
Enabling GMRP on Individual Ports.............................................................................................	157
Disabling GMRP on Individual Ports...........................................................................................	157
Enabling GMRP Forward−All ......................................................................................................	157
Disabling GMRP Forward−All .....................................................................................................	157
Configuring GMRP Registration...................................................................................................	157
Displaying the GMRP Configuration............................................................................................	158
Setting GMRP Timers...................................................................................................................	158
Displaying GMRP Timers.............................................................................................................	158
Configuring Bandwidth−Based Suppression.......................................................................................	159

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Table of Contents
Chapter 7: IP Multicast
Configuring Packet−Based Suppression..............................................................................................	159
Disabling Multicast Suppression.........................................................................................................	159
Chapter 8: WAN Cell Switching...................................................................................................................	160
In Depth...............................................................................................................................................	160
ATM Overview....................................................................................................................................	160
LANE............................................................................................................................................	161
ATM Protocols..............................................................................................................................	162
ATM Circuit Switching.................................................................................................................	162
ATM Cells.....................................................................................................................................	162
The ATM Switch and ATM Endpoints.........................................................................................	164
The ATM Reference Model..........................................................................................................	164
Specifying ATM Connections.......................................................................................................	166
ATM Addressing...........................................................................................................................	167
Local Area Network Emulation (LANE).............................................................................................	167
LANE Components.......................................................................................................................	168
Integrated Local Management Interface (ILMI)...........................................................................	172
LANE Communication..................................................................................................................	172
LANE Configuration Guidelines...................................................................................................	174
How LANE Works........................................................................................................................	174
Implementing LANE.....................................................................................................................	175
Configuring ATM on the 5000 Switch..........................................................................................	175
Connecting in an ATM Network...................................................................................................	177
Monitoring and Maintaining LANE....................................................................................................	178
Accessing the ATM LANE Module....................................................................................................	178
Displaying the Selector Field...............................................................................................................	178
Configuring the LES/BUS...................................................................................................................	179
Verifying the LES/BUS Configuration.........................................................................................	179
Configuring a LEC for an ELAN.........................................................................................................	179
Verifying a LEC Configuration on an ELAN...............................................................................	180
Configuring the LECS...................................................................................................................	181
Viewing the LANE Database........................................................................................................	181
Binding the LECS Address to an Interface...................................................................................	181
Verifying the LECS Configuration...............................................................................................	182
Chapter 9: LightStream Switches.................................................................................................................	183
In Depth...............................................................................................................................................	183
LightStream 100..................................................................................................................................	183
LightStream 1010................................................................................................................................	184
LightStream 2020................................................................................................................................	185
Neighborhood Discovery Function...............................................................................................	186
Virtual Path Connections.....................................................................................................................	186
LightStream Troubleshooting Tools....................................................................................................	187
LightStream Boot Process.............................................................................................................	187
Supported Troubleshooting Protocols...........................................................................................	188
Snooping Mechanisms..................................................................................................................	188
Multiprotocol Over ATM..............................................................................................................	188
Configuring the Hostname...................................................................................................................	189
Configuring an Enable Password.........................................................................................................	189
Configuring the Processor Card Ethernet Interface.............................................................................	189
Configuring Virtual Private Tunnels...................................................................................................	190

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Chapter 9: LightStream Switches
Verifying an ATM Interface Connection Status..................................................................................	190
Viewing the Configured Virtual Connections.....................................................................................	191
Configuring the LECS ATM Address on a LightStream 1010 Switch...............................................	191
Configuring the Advertised LECS Address.........................................................................................	191
Viewing the LANE Configuration.......................................................................................................	191
Viewing the Installed Modules............................................................................................................	192
Configuring the MPC...........................................................................................................................	193
Configuring the MPS...........................................................................................................................	193
Changing the MPS Variables........................................................................................................	193
Monitoring the MPS......................................................................................................................	194
Enabling ILMI Autoconfiguration.......................................................................................................	194
Configuring LANE on a LightStream 1010.........................................................................................	194
Powering on the LightStream 100 ATM Switch.................................................................................	195
Configuring the LS100 Switch............................................................................................................	195
Recovering a Lost Password................................................................................................................	196
Chapter 10: Layer 2 Redundant Links.........................................................................................................	199
In Depth...............................................................................................................................................	199
Layer 2 Switching Overview...............................................................................................................	199
Frames..................................................................................................................................................	199
Broadcast and Multicast Frames...................................................................................................	200
Unknown Unicasts........................................................................................................................	200
Layer 2 Network Loops.......................................................................................................................	200
Danger! Data Loops!.....................................................................................................................	201
Edsger Dijkstra’s Graph Theory....................................................................................................	201
STP Root Bridges..........................................................................................................................	202
Bridge Protocol Data Units...........................................................................................................	203
Root Bridge Selection...................................................................................................................	205
Spanning Tree Convergence Time................................................................................................	207
STP Port States..............................................................................................................................	208
Per−VLAN Spanning Tree............................................................................................................	209
EtherChannel........................................................................................................................................	209
Link Failure...................................................................................................................................	210
Port Aggregation Protocol.............................................................................................................	210
Fast Convergence Components of STP...............................................................................................	211
PortFast..........................................................................................................................................	211
UplinkFast.....................................................................................................................................	211
BackboneFast................................................................................................................................	212
Enabling STP on a Set/Clear Command−Based Switch......................................................................	212
Enabling STP on a Set/Clear Command−Based Switch for All VLANs............................................	213
Disabling STP on a Set/Clear Command−Based Switch.....................................................................	213
Disabling STP on a Set/Clear Command−Based Switch by VLAN...................................................	213
Viewing the STP Configuration on a Set/Clear Command−Based Switch.........................................	213
Configuring STP on an IOS Command−Based Switch.......................................................................	214
Disabling STP on an IOS Command−Based Switch...........................................................................	214
Viewing the STP Configuration on a Command Line Switch.............................................................	215
Configuring the STP Root Switch.......................................................................................................	215
Configuring the STP Secondary Root Switch.....................................................................................	215
Setting the Root Bridge for More than One VLAN on a Set/Clear Command−Based Switch...........	216
Assigning a Port Cost to a Port Using the Set/Clear Command−Based IOS......................................	216
Assigning a Port Cost to a Port Using a CLI−Based Switch...............................................................	216

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Chapter 10: Layer 2 Redundant Links
Verifying the Port Cost Configuration on Both a Set/Clear Command− and CLI−Based Interface...	217
Configuring the Port Priority on a Set/Clear Command−Based IOS..................................................	217
Configuring the Port Priority on a CLI−Based IOS............................................................................	217
Verifying the STP Port Priority on a Set/Clear Command−Based Switch..........................................	218
Verifying the VLAN Priority Settings.................................................................................................	218
Adjusting the FwdDelay Timer on a Set/Clear Command−Based IOS...............................................	218
Adjusting the Hello Timer on a Set/Clear Command−Based IOS......................................................	218
Adjusting the MaxAge Timer on a Set/Clear Command−Based IOS.................................................	219
Preparing to Enable EtherChannel.......................................................................................................	219
Viewing the Port Setting for EtherChannel on a Set/Clear Command−Based Switch........................	219
Creating an EtherChannel on a Set/Clear Command−Based Switch..................................................	220
Verifying the EtherChannel Configuration..........................................................................................	221
Defining an EtherChannel Administrative Group...............................................................................	221
Viewing an EtherChannel Administrative Group................................................................................	221
Configuring EtherChannel on an IOS−Based Switch..........................................................................	222
Identifying the Template Port..............................................................................................................	222
Verifying the EtherChannel Configuration on a Command Line Interface IOS.................................	222
Enabling PortFast on a Set/Clear Command−Based Switch...............................................................	223
Disabling PortFast on a Set/Clear Command−Based Switch..............................................................	223
Enabling PortFast on a CLI−Based IOS Switch..................................................................................	223
Disabling PortFast on a CLI−Based IOS Switch.................................................................................	224
Verifying the PortFast Configuration..................................................................................................	224
Enabling UplinkFast on a Set/Clear Command−Based Switch...........................................................	224
Disabling UplinkFast on a Set/Clear Command−Based Switch..........................................................	224
Verifying the UplinkFast Configuration..............................................................................................	225
Enabling UplinkFast on a Cisco IOS Command−Based Switch.........................................................	225
Disabling UplinkFast on a Cisco IOS Command−Based Switch........................................................	225
Viewing the UplinkFast Configuration on an IOS−Based Switch......................................................	226
Viewing UplinkFast Statistics on an IOS−Based Switch....................................................................	226
Enabling BackboneFast on a Set/Clear Command−Based Switch......................................................	226
Disabling BackboneFast on a Set/Clear Command−Based Switch.....................................................	226
Viewing the BackboneFast Configuration...........................................................................................	226
Chapter 11: Multilayer Switching.................................................................................................................	227
In Depth...............................................................................................................................................	227
How MLS Works.................................................................................................................................	227
MLS Components..........................................................................................................................	228
MLS Flows....................................................................................................................................	230
Access List Flow Masks................................................................................................................	231
MLS Troubleshooting Notes...............................................................................................................	232
Configuring MLS.................................................................................................................................	233
MLS Cache....................................................................................................................................	234
Aging Timers.................................................................................................................................	234
VLAN ID.......................................................................................................................................	235
VTP Domain..................................................................................................................................	235
Management Interfaces.................................................................................................................	235
Configuring an External MLS Route Processor..................................................................................	235
Enabling MLSP on an MLS−RP for IP.........................................................................................	236
Disabling MLSP on an MLS−RP for IP........................................................................................	236
Enabling MLSP on an MLS−RP for IPX......................................................................................	236
Disabling MLSP on an MLS−RP for IPX.....................................................................................	236

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Table of Contents
Chapter 11: Multilayer Switching
Assigning a VLAN ID...................................................................................................................	236
Adding an MLS Interface to a VTP Domain................................................................................	236
Enabling MLS on an Individual Interface.....................................................................................	237
Disabling MLS on an External Router Interface...........................................................................	237
Configuring the MLS Switch Engine..................................................................................................	237
Re−enabling MLS on a Catalyst 6000..........................................................................................	237
Re−enabling MLS on a Catalyst 5000..........................................................................................	238
Disabling MLS on a Catalyst 6000...............................................................................................	238
Disabling MLS on a Catalyst 5000...............................................................................................	238
Configuring the MLS Cache on the Catalyst 5000.......................................................................	238
Configuring Fast Aging on a Catalyst 5000..................................................................................	238
Configuring Fast Aging on a Catalyst 6000..................................................................................	238
Disabling Fast Aging on a Catalyst 6000......................................................................................	238
Configuring Long Aging on the Catalyst 6000.............................................................................	239
Disabling Long Aging on the Catalyst 6000.................................................................................	239
Configuring Normal Aging on the Catalyst 6000.........................................................................	239
Disabling Normal Aging on the Catalyst 6000.............................................................................	239
Assigning MLS Management to an Interface on the Catalyst 5000..............................................	239
Disabling MLS Management on an Interface on the Catalyst 5000.............................................	239
Monitoring and Viewing the MLS Configuration...............................................................................	240
Viewing the MLS Aging Configuration on a Catalyst 6000.........................................................	240
Displaying the IP MLS Configuration..........................................................................................	240
Viewing MLS−RPs .......................................................................................................................	240
Viewing MLS−RP Specifics.........................................................................................................	240
Displaying MLS VTP Domain Information..................................................................................	241
Viewing the MLS VLAN Interface Information...........................................................................	241
Viewing MLS Statistics on the Catalyst 5000...............................................................................	241
Viewing MLS Statistics on the Catalyst 6000...............................................................................	242
Viewing MLS Entries....................................................................................................................	242
Chapter 12: Hot Standby Routing Protocol.................................................................................................	243
In Depth...............................................................................................................................................	243
Routing Problems................................................................................................................................	243
Routing Information Protocol.......................................................................................................	244
Proxy ARP.....................................................................................................................................	244
ICMP Router Discovery Protocol.................................................................................................	244
The Solution.........................................................................................................................................	245
HSRP Message Format.................................................................................................................	247
The HSRP States...........................................................................................................................	247
HSRP Configuration............................................................................................................................	248
HSRP Interface Tracking.....................................................................................................................	248
Opening a Session on an Internal Route Processor.............................................................................	249
Entering Configuration Mode on an RSM...........................................................................................	249
Enabling HSRP and Assigning an IP Address to a Standby Group....................................................	249
Assigning an HSRP Interface Priority.................................................................................................	250
Assigning a Preempt Delay to a Standby Group.................................................................................	250
Removing a Preempt Delay from a Standby Group............................................................................	250
Setting the HSRP Hello and Hold Timers...........................................................................................	250
Removing the HSRP Hello and Hold Timers......................................................................................	251
Configuring a Clear−Text Password for HSRP Authentication..........................................................	251
Configuring Two RSFC Interfaces as One HSRP Group....................................................................	251

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Table of Contents
Chapter 12: Hot Standby Routing Protocol
Enabling Interface Tracking................................................................................................................	252
Using the show standby Command.....................................................................................................	252
Using the debug Command..................................................................................................................	253
Chapter 13: Policy Networking.....................................................................................................................	254
In Depth...............................................................................................................................................	254
Access Security Policies......................................................................................................................	254
Core Layer Policies.......................................................................................................................	255
Distribution Layer Policies............................................................................................................	255
Security at the Access Layer................................................................................................................	261
Configuring Passwords..................................................................................................................	261
Limiting Telnet Access.................................................................................................................	261
Implementing Privilege Levels.....................................................................................................	261
Configuring Banner Messages......................................................................................................	262
Physical Device Security...............................................................................................................	262
Port Security..................................................................................................................................	262
VLAN Management......................................................................................................................	263
Creating a Standard Access List..........................................................................................................	263
Creating an Extended Access List.......................................................................................................	264
Applying Access Lists Using access−class .........................................................................................	266
Applying Access Lists Using distribute−list .......................................................................................	266
Configuring a Telnet Session Time−Out Value..................................................................................	267
Implementing Privilege Levels on a 1900EN......................................................................................	267
Configuring Line Console Time−Out Values......................................................................................	267
Configuring Banner Messages.............................................................................................................	268
Enabling HTTP Access........................................................................................................................	268
Enabling Port Security.........................................................................................................................	269
Displaying the MAC Address Table....................................................................................................	270
Chapter 14: Web Management......................................................................................................................	272
In Depth...............................................................................................................................................	272
Standard and Enterprise Edition CVSM..............................................................................................	272
CVSM Client Requirements................................................................................................................	272
CVSM Access Levels..........................................................................................................................	273
CVSM Default Home Page..................................................................................................................	273
The Switch Image..........................................................................................................................	274
Configuring the Switch with an IP Address and Setting the Default Web Administration Port.........	275
Connecting to the Web Management Console.....................................................................................	276
Configuring the Switch Port Analyzer.................................................................................................	281
Chapter 15: The Standard Edition IOS........................................................................................................	283
In Depth...............................................................................................................................................	283
The 1900 and 2820 Series Switches....................................................................................................	283
Main Menu Choices......................................................................................................................	283
[C] Console Settings......................................................................................................................	284
[S] System Menu...........................................................................................................................	285
[N] Network Management.............................................................................................................	286
[P] Port Configuration...................................................................................................................	289
[A] Port Addressing.......................................................................................................................	292
[D] Port Statistics Detail................................................................................................................	293
[M] Monitor...................................................................................................................................	293

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Table of Contents
Chapter 15: The Standard Edition IOS
[V] Virtual LAN............................................................................................................................	293
[R] Multicast Registration.............................................................................................................	294
[F] Firmware..................................................................................................................................	294
[I] RS−232 Interface......................................................................................................................	295
[U] Usage Summaries...................................................................................................................	296
Configuring Network Settings on the 1900 and 2820 Series...............................................................	298
Configuring Broadcast Storm Control on Switch Ports.......................................................................	299
Configuring SNMP on the 1900 Series...............................................................................................	300
Configuring Port Monitoring on the Standard Edition IOS.................................................................	303
Configuring VLANs on the Standard Edition IOS..............................................................................	304
Configuring Spanning Tree Protocol...................................................................................................	307
Chapter 16: Switch Troubleshooting............................................................................................................	309
In Depth...............................................................................................................................................	309
Hardware Troubleshooting..................................................................................................................	309
No Power.......................................................................................................................................	309
POST.............................................................................................................................................	309
Indicator Lights.............................................................................................................................	310
Switch Cabling.....................................................................................................................................	311
Cable Problems..............................................................................................................................	312
Cross−Over Cables........................................................................................................................	312
Switch Troubleshooting Tools.............................................................................................................	312
CiscoWorks for Switched Internetworks......................................................................................	312
IOS Software Troubleshooting Commands..................................................................................	313
Viewing the Set/Clear IOS Configuration...........................................................................................	316
Viewing the CLI−Based IOS Configuration.......................................................................................	320
Viewing the Software Version on a Set/Clear Command−Based IOS Module..................................	321
Viewing the IOS Version Information on a CLI−Based IOS..............................................................	321
Using the show flash Command on a Set/Clear Command−Based IOS.............................................	321
Testing the Supervisor Engine Hardware on a Set/Clear Command−Based Switch...........................	322
Testing External Module Hardware on a Set/Clear Command−Based Switch...................................	323
Viewing the System Configuration on a Set/Clear Command−Based Switch....................................	323
Viewing the VTP Domain Configuration on a Set/Clear IOS.............................................................	324
Viewing the VTP Domain Configuration on a CLI−Based IOS.........................................................	324
Viewing the VLAN Configuration on a Set/Clear Command−Based Switch.....................................	324
Viewing the VLAN Configuration on a CLI−Based IOS....................................................................	325
Viewing the Spanning Tree Configuration on a Set/Clear Command−Based IOS.............................	325
Viewing the Spanning Tree Configuration on a CLI−Based IOS.......................................................	326
Viewing the CAM (MAC Address) Table on a Set/Clear Command−Based IOS..............................	328
Viewing the CAM (MAC Address) Table on a CLI−Based IOS........................................................	328
Viewing the CDP Neighbors on a Set/Clear Command−Based IOS...................................................	329
Viewing the CDP Neighbors on a CLI−Based IOS.............................................................................	329
Viewing Individual Port CAM Tables on a CLI−Based IOS..............................................................	330
Viewing Port Statistics on a Set/Clear IOS.........................................................................................	330
Viewing Port Statistics on a CLI−Based IOS......................................................................................	332
Using the Port Configuration on a Set/Clear Command−Based IOS..................................................	333
Using the show port Command on a CLI−Based IOS.........................................................................	333
Using the show vlan Command on a Set/Clear Command−Based IOS..............................................	334
Using the show vlan Command on a CLI−Based IOS........................................................................	334
Using the show interface Command on a Set/Clear Command−Based IOS.......................................	335
Using the show interface Command on a CLI−Based IOS.................................................................	335

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Table of Contents
Chapter 16: Switch Troubleshooting
Using the show log Command on a Set/Clear Command−Based IOS................................................	336
Configuring SPAN for Port Monitoring on a Set/Clear Command−Based IOS.................................	337
Configuring SPAN for VLAN Monitoring on a Set/Clear Command−Based IOS.............................	337
Launching the Diagnostic Console on a Cisco 1900 or 2820 Series Switch.......................................	337
Using the Diagnostic Console to Upgrade the Firmware on a Cisco 1900 or 2820 Series Switch.....	338
Using the Diagnostic Console for Debugging the Firmware and Hardware.......................................	339
Appendix A: Study Resources.......................................................................................................................	341
Books...................................................................................................................................................	341
Cisco Group Study and Users Groups.................................................................................................	341
Live Cisco Training/Internet−Based Labs/Study Resources...............................................................	341
Online Resources.................................................................................................................................	342
Asynchronous Transfer Mode.......................................................................................................	342
Cisco IOS......................................................................................................................................	342
Hot Standby Router Protocol........................................................................................................	342
Inter−Switch Link.........................................................................................................................	342
IP Multicast...................................................................................................................................	342
Multilayer Switching.....................................................................................................................	342
Quality of Service..........................................................................................................................	343
Spanning Tree Protocol.................................................................................................................	343
TACACS+.....................................................................................................................................	343
VLANs..........................................................................................................................................	343
Standards Organizations......................................................................................................................	343
Cisco Job Search Sites.........................................................................................................................	344
Appendix B: Basic IOS CLI−to−Set/Clear Commands..............................................................................	345
Overview..............................................................................................................................................	345
Appendix C: The Cisco Consultant...............................................................................................................	347
Overview..............................................................................................................................................	347
Establishing Credibility.......................................................................................................................	347
Come Off As an Expert.................................................................................................................	348
Designing a Solution............................................................................................................................	348
Estimating the Cost.......................................................................................................................	349
Presenting the Final Proposal and Creating Expectations.............................................................	349
Contracting...........................................................................................................................................	350
Document, Document, Document........................................................................................................	350
The Way to Fail...................................................................................................................................	350
Failing to Be There When Promised, or Rushing through the Job................................................	350
Failing to Manage Your Time.......................................................................................................	351
Assuming You Know What the Customer Needs.........................................................................	351
Failing to Take Responsibility......................................................................................................	352
Conclusion...........................................................................................................................................	352
Appendix D: Cisco 1912EN and Catalyst 5000 Configuration Practice Lab............................................	353
Required Equipment............................................................................................................................	353
Lab Objectives.....................................................................................................................................	354
Possible Solution..................................................................................................................................	355
The 1912 Basic Configuration......................................................................................................	355
The Catalyst 5000 Basic Configuration........................................................................................	357
Configuring the Cisco 2621 Interface for ISL Trunking...............................................................	358

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Table of Contents
Appendix E: Switch Features........................................................................................................................	359
Access Layer Switches........................................................................................................................	359
Cisco Catalyst 1900.......................................................................................................................	359
Cisco Catalyst 2820.......................................................................................................................	360
Cisco Catalyst 2900.......................................................................................................................	360
Cisco Catalyst 3000.......................................................................................................................	362
Cisco Catalyst 3500 Series XL......................................................................................................	362
Cisco Catalyst 3900 Series............................................................................................................	363
Distribution Layer Switches................................................................................................................	364
Cisco Catalyst 4000 Series............................................................................................................	365
Catalyst 5000 Series......................................................................................................................	365
Catalyst 6000 Series......................................................................................................................	366
Core Layer/WAN Switches.................................................................................................................	367
Cisco Catalyst 8400 Series............................................................................................................	368
Cisco Catalyst 8500 Series............................................................................................................	369
BPX 8600 Series...........................................................................................................................	370
MGX 8800 Series..........................................................................................................................	371
12000 Series Gigabit Switch Routers............................................................................................	372
A....................................................................................................................................................	373
B....................................................................................................................................................	375
C....................................................................................................................................................	376
D....................................................................................................................................................	378
E−F ................................................................................................................................................	380
G−I ................................................................................................................................................	382
K−L ...............................................................................................................................................	385
M−N ..............................................................................................................................................	386
O−P................................................................................................................................................	388
Q−R ...............................................................................................................................................	390
S.....................................................................................................................................................	391
T.....................................................................................................................................................	393
U−X...............................................................................................................................................	395

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