Cisco WS-C4003 - Catalyst 4000 Chassis Switch User manual

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Software Configuration Guide
Catalyst 4000 Family
Catalyst 2948G
Catalyst 2980G
Software Releases 6.3 and 6.4
Customer Order Number: DOC-7812647=
Text Part Number: 78-12647-02

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Software Configuration Guide—Catalyst 4000 Family, Catalyst 2948G, Catalyst 2980G, Releases 6.3 and 6.4
Copyright © 2000-2003, Cisco Systems, Inc.
All rights reserved.

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78-12647-02
CONTENTS
Preface xxiii
Audience xxiii
Organization xxiii
Related Documentation xxv
Conventions xxvi
Obtaining Documentation xxvii
World Wide Web xxvii
Documentation CD-ROM xxvii
Ordering Documentation xxvii
Documentation Feedback xxviii
Obtaining Technical Assistance xxviii
Cisco.com xxviii
Technical Assistance Center xxviii
Cisco TAC Web Site xxix
Cisco TAC Escalation Center xxix
PART 1Getting Started
CHAPTER 1Product Overview 1-1
Catalyst 4000 Family Switches 1-1
Catalyst 2948G Switch 1-2
Catalyst 2980G Switch 1-2
Supervisor Engine Software 1-3
CHAPTER 2Using the Command-Line Interface 2-1
Overview of the Switch CLI 2-1
Accessing the Switch CLI 2-2
Accessing the CLI through the Console Port 2-2
Accessing the CLI Through Telnet 2-2
Switch CLI Command Modes 2-3
Accessing Help 2-4
Command-Line Editing 2-5
History Substitution 2-5

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Abbreviating a Command 2-6
Completing a Partial Command 2-6
Scrolling Down a Line or a Screen 2-7
Using Command Aliases 2-7
Specifying Modules, Ports, and VLANs 2-7
Specifying MAC Addresses 2-8
Specifying IP Addresses, Host Names, and IP Aliases 2-8
ROM Monitor Command-Line Interface 2-9
Catalyst 4003 Bootup Display Example 2-9
CHAPTER 3Configuring the Switch IP Address and Default Gateway 3-1
Understanding the Switch Management Interfaces 3-1
Understanding Automatic IP Configuration 3-2
Automatic IP Configuration Overview 3-2
Understanding How DHCP Works 3-3
Understanding How RARPWorks 3-4
Preparing to Configure the IP Address and Default Gateway 3-4
Default IP Address and Default Gateway Configuration 3-5
Setting the In-Band (sc0) Interface IP Address 3-5
Setting the Management Ethernet (me1) Interface IP Address 3-6
Configuring Default Gateways 3-7
Configuring the SLIP (sl0) Interface on the Console Port 3-8
Using DHCP or RARP to Obtain an IP Address Configuration 3-10
Renewing and Releasing a DHCP-Assigned IP Address 3-11
PART 2Configuring Ethernet Switching
CHAPTER 4Configuring Ethernet and Fast EthernetSwitching 4-1
Understanding How Ethernet Works 4-1
Ethernet Overview 4-1
Switching Frames Between Segments 4-2
Building the Address Table 4-2
Default Ethernet and Fast Ethernet Configuration 4-2
Configuring Ethernetand Fast Ethernet Ports 4-3
Setting the Port Name 4-3
Setting the Port Priority Level 4-4
Setting the Port Speed 4-4

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Setting the Port Duplex Mode 4-5
Configuring a Timeout Period for Ports in errdisable State 4-6
Checking Connectivity 4-7
CHAPTER 5Configuring Gigabit Ethernet Switching 5-1
Understanding How GigabitEthernet Works 5-1
Understanding How Gigabit Ethernet Flow Control Works 5-1
Flow-Control Overview 5-1
Sending and Receiving Pause Frames 5-2
Using Flow-Control Keywords 5-2
Understanding How Port Negotiation Works 5-3
Understanding How Oversubscribed Gigabit Ethernet Works 5-3
Oversubscribed Gigabit Ethernet Overview 5-4
Oversubscribed Gigabit Ethernet Example 5-5
Default Gigabit Ethernet Configuration 5-6
Configuring Gigabit Ethernet 5-6
Setting the Port Name 5-7
Setting the Port Priority Level 5-7
Configuring Flow Control on Gigabit Ethernet Ports 5-8
Configuring Port Negotiation on Gigabit Ethernet Ports 5-8
Configuring a Timeout Period for Ports in errdisable State 5-9
Checking Connectivity 5-9
CHAPTER 6Configuring Fast EtherChannel and Gigabit EtherChannel 6-1
Understanding How EtherChannel Works 6-1
EtherChannel Overview 6-2
Understanding Administrative Groups and EtherChannel IDs 6-2
Understanding the Port Aggregation Protocol 6-2
Understanding Frame Distribution 6-3
Default EtherChannel Configuration 6-4
Hardware Support for EtherChannel 6-4
EtherChannel Configuration Guidelines and Restrictions 6-4
Configuring EtherChannel 6-5
Creating an EtherChannel 6-5
Defining an EtherChannel Administrative Group 6-6
Setting the EtherChannel Spanning Tree Port Cost 6-7
Setting the EtherChannel Spanning Tree PortVLAN Cost 6-7
Removing an EtherChannel Bundle 6-8
Displaying EtherChannel Configuration Information 6-9

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Displaying EtherChannel Traffic Statistics 6-10
Displaying EtherChannel PAgP Statistics 6-11
EtherChannel Configuration Examples 6-11
Four-Port Fast EtherChannel Configuration Example 6-11
Two-Port Gigabit EtherChannel Configuration Example 6-13
PART 3Spanning Tree
CHAPTER 7Configuring Spanning Tree 7-1
How Spanning Tree Protocols Work 7-1
How a Topology Is Created 7-2
How a Switch orPort Becomes the Root Switch or Root Port 7-3
How Bridge Protocol Data Units Work 7-3
Spanning Tree Port States 7-4
Blocking State 7-5
Listening State 7-7
Learning State 7-8
Forwarding State 7-9
Disabled State 7-9
Understanding PVST+ and MISTP Modes 7-10
PVST+ Mode 7-11
MISTP Mode 7-11
MISTP-PVST+ Mode 7-11
Bridge Identifiers 7-12
MAC Address Allocation 7-12
MAC Address Reduction 7-12
Using PVST+ 7-12
Default PVST+ Configuration 7-13
Configuring PVST+ Bridge ID Priority 7-13
Configuring PVST+ Port Cost 7-15
Configuring PVST+ Port Priority 7-15
Configuring PVST+ Default Port Cost Mode 7-16
Configuring PVST+ Port VLAN Cost 7-16
Configuring PVST+ Port VLAN Priority 7-17
Disabling the PVST+ Mode on a VLAN 7-18
Using MISTP-PVST+ or MISTP 7-18
Default MISTP Configuration 7-19
Enabling MISTP-PVST+ or MISTP 7-19
Configuring a MISTP Instance 7-21

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Configuring MISTP BridgeID Priority 7-21
Configuring MISTP Port Cost 7-22
Configuring MISTP Port Priority 7-22
Configuring MISTP Port Instance Cost 7-23
Configuring MISTP Port Instance Priority 7-23
Enabling a MISTP Instance 7-24
Mapping VLANs to a MISTP Instance 7-25
Determining MISTP Instance—VLAN Mapping Conflicts 7-25
Unmapping VLANs from a MISTP Instance 7-26
Disabling MISTP-PVST+ or MISTP 7-26
Configuring a Root Switch 7-27
Configuring a Primary Root Switch 7-27
Configuring a Secondary Root Switch 7-28
Configuring a Root Switch to Improve Convergence 7-29
Using Root Guard—Preventing Switches from Becoming Root 7-30
Configuring Spanning Tree Timers 7-30
Configuring Hello Time 7-31
Configuring Forward Delay Time 7-31
Configuring Maximum Aging Time 7-32
Understanding How BPDU Skewing Works 7-33
Configuring Spanning Tree BPDU Skewing 7-33
CHAPTER 8Configuring Spanning Tree PortFast, UplinkFast, and BackboneFast,and Loop Guard 8-1
Understanding How PortFast Works 8-1
Configuring PortFast 8-2
Enabling Spanning Tree PortFast 8-2
Disabling Spanning Tree PortFast 8-3
Understanding How PortFast BPDU Guard Works 8-3
Configuring PortFast BPDU Guard 8-3
Enabling PortFast BPDU Guard 8-4
Disabling PortFast BPDU Guard 8-5
Understanding How PortFast BPDU Filtering Works 8-6
Configuring PortFast BPDU Filtering 8-6
Enabling PortFast BPDU Filtering 8-6
Disabling PortFast BPDU Filtering 8-7
Understanding How UplinkFast Works 8-8
Configuring UplinkFast 8-9

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Enabling UplinkFast 8-9
Disabling UplinkFast 8-10
Understanding How BackboneFast Works 8-11
Configuring BackboneFast 8-13
Enabling BackboneFast 8-13
Displaying BackboneFast Statistics 8-14
Disabling BackboneFast 8-14
Understanding How Loop Guard Works 8-15
Configuring Loop Guard 8-17
Enabling Loop Guard 8-17
Disabling Loop Guard 8-17
PART 4Configuring VLANs and VLAN Trunks
CHAPTER 9Configuring VTP 9-1
Understanding How VTP Works 9-1
VTP Domain 9-2
VTP Modes 9-2
VTP Advertisements 9-2
VTP Version 2 9-3
VTP Pruning 9-3
Default VTP Configuration 9-5
VTP Configuration Guidelines 9-5
Configuring VTP 9-5
Configuring a VTP Server 9-6
Configuring a VTP Client 9-6
Disabling VTP (VTP Transparent Mode) 9-7
Enabling VTP Version 2 9-7
Disabling VTP Version 2 9-8
Configuring VTP Pruning 9-9
Disabling VTP Pruning 9-10
Monitoring VTP 9-10
CHAPTER 10 Configuring VLANs 10-1
Understanding How VLANs Work 10-1
VLAN Default Configuration 10-3
VLAN Configuration Guidelines 10-3
Configuring VLANs 10-3

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Creating or Modifying an Ethernet VLAN 10-4
Assigning Switch Ports to a VLAN 10-4
Mapping 802.1Q VLANs to ISL VLANs 10-5
Clearing 802.1Q-to-ISL VLAN Mappings 10-6
Deleting a VLAN 10-7
Configuring PrivateVLANs 10-7
Understanding How Private VLANs Work 10-7
Private VLAN Configuration Guidelines 10-9
Creating a Private VLAN 10-10
Viewing the Port Capability of a Private VLAN Port 10-13
Deleting a Private VLAN 10-13
Deleting an Isolated orCommunity VLAN 10-14
Deleting a Private VLAN Mapping 10-14
CHAPTER 11 Configuring VLAN Trunks on Fast Ethernet and Gigabit Ethernet Ports 11-1
Understanding How VLAN Trunks Work 11-1
Trunking Overview 11-1
Trunking Modes and Encapsulation Types 11-2
Trunking Support 11-4
802.1Q Trunk Restrictions 11-4
Default Trunk Configuration 11-5
Configuring a Trunk Link 11-5
Configuring an 802.1Q Trunk 11-5
Defining the Allowed VLANs on a Trunk 11-6
Disabling a Trunk Port 11-7
Example VLAN Trunk Configurations 11-7
802.1Q Trunk over GigabitEtherChannel Link Example 11-8
Load-Sharing VLAN Traffic over Parallel Trunks Example 11-11
802.1Q Nonegotiate Trunk Configuration Example 11-18
Disabling VLAN 1 on a Trunk Link 11-21
CHAPTER 12 Configuring Dynamic PortVLAN Membership with VMPS 12-1
Understanding How VMPS Works 12-1
VMPS and Dynamic Port Hardware and Software Requirements 12-2
Default VMPS and Dynamic Port Configuration 12-2
Dynamic Port VLAN Membership and VMPS Configuration Guidelines 12-3

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Configuring VMPS and Dynamic Port VLAN Membership 12-3
Creating the VMPS Database 12-3
Configuring VMPS 12-4
Configuring Dynamic Ports on VMPS Clients 12-5
Configuring Static VLAN Port Membership 12-6
Troubleshooting VMPS and Dynamic Port VLAN Membership 12-6
Troubleshooting VMPS 12-6
Troubleshooting Dynamic Port VLAN Membership 12-7
Dynamic Port VLAN Membership with VMPS Configuration Examples 12-7
VMPS Database Configuration File Example 12-7
Dynamic Port VLAN Membership Configuration Example 12-8
Dynamic Port VLAN Membership with Auxiliary VLANs 12-10
Configuration Guidelines 12-11
Configuring Dynamic Port VLAN Membership with Auxiliary VLANs 12-11
CHAPTER 13 Configuring GVRP 13-1
Understanding How GVRP Works 13-1
GVRP Hardware and Software Requirements 13-1
Default GVRP Configuration 13-2
GVRP Configuration Guidelines 13-2
Configuring GVRP 13-2
Enabling GVRP Globally 13-3
Enabling GVRP on Individual 802.1Q Trunk Ports 13-3
Enabling GVRP Dynamic VLAN Creation 13-4
Configuring GVRP Registration 13-5
Setting GVRP Normal Registration 13-5
Setting GVRP Fixed Registration 13-5
Setting GVRP Forbidden Registration 13-5
SendingGVRP VLAN Declarations from Blocking Ports 13-6
Setting the GARP Timers 13-6
Displaying GVRP Statistics 13-7
Clearing GVRP Statistics 13-8
Disabling GVRP on Individual 802.1Q Trunk Ports 13-8
Disabling GVRP Globally 13-8