Cisco 2950G 24 - Catalyst Switch User manual

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Catalyst 2950 Desktop Switch Software
Configuration Guide
Cisco IOS Release 12.1(11)EA1 and 12.1(11)YJ
November 2002
Customer Order Number: DOC-7814982=
Text Part Number: 78-14982-01

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Catalyst 2950 Desktop Switch Software Configuration Guide
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CONTENTS
Preface xxv
Audience xxv
Purpose xxv
Organization xxvi
Conventions xxviii
Related Publications xxix
Obtaining Documentation xxix
World Wide Web xxix
Documentation CD-ROM xxx
Ordering Documentation xxx
Documentation Feedback xxx
Obtaining Technical Assistance xxx
Cisco.com xxxi
Technical Assistance Center xxxi
Cisco TAC Website xxxi
Cisco TAC Escalation Center xxxii
CHAPTER 1Overview 1-1
Features 1-1
ManagementOptions 1-7
ManagementInterface Options 1-7
Advantages of Using CMS and Clustering Switches 1-7
Network Configuration Examples 1-8
Design Concepts for Using the Switch 1-8
Small to Medium-Sized Network Configuration 1-11
Collapsed Backbone and Switch Cluster Configuration 1-13
Large Campus Configuration 1-14
Hotel Network Configuration 1-16
Multidwelling Network Using Catalyst 2950 Switches 1-18
Long-Distance, High-Bandwidth Transport Configuration 1-20
Where to Go Next 1-21

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CHAPTER 2Using the Command-Line Interface 2-1
IOS Command Modes 2-1
Getting Help 2-3
Specifying Ports in Interface Configuration Mode 2-4
Abbreviating Commands 2-5
Using no and default Forms ofCommands 2-5
Understanding CLI Messages 2-5
Using Command History 2-6
Changing the Command History Buffer Size 2-6
Recalling Commands 2-6
Disabling the Command History Feature 2-7
Using Editing Features 2-7
Enabling and Disabling Editing Features 2-7
Editing Commands through Keystrokes 2-8
Editing Command Lines that Wrap 2-9
Searching and Filtering Output of show and more Commands 2-10
Accessing the CLI 2-10
Accessing the CLI from a Browser 2-11
CHAPTER 3Getting Started with CMS 3-1
Features 3-2
Front Panel View 3-4
Cluster Tree 3-6
Front-PanelImages 3-7
Redundant Power System LED 3-8
Port Modes and LEDs 3-8
VLAN Membership Modes 3-9
Topology View 3-10
Topology Icons 3-12
Device and Link Labels 3-13
Colors in the Topology View 3-14
Topology Display Options 3-15
Menus and Toolbar 3-15
Menu Bar 3-15
Toolbar 3-20
Front Panel View Popup Menus 3-21
Device Popup Menu 3-21
Port Popup Menu 3-21

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Topology View Popup Menus 3-22
Link Popup Menu 3-22
Device Popup Menus 3-23
Interaction Modes 3-25
Guide Mode 3-25
Expert Mode 3-25
Wizards 3-26
ToolTips 3-26
Online Help 3-26
CMS Window Components 3-28
Host Name List 3-28
Tabs, Lists, and Tables 3-29
Filter Editor 3-29
Icons Used in Windows 3-29
Buttons 3-30
Accessing CMS 3-30
Access Modes in CMS 3-31
HTTP Access to CMS 3-32
Verifying Your Changes 3-32
Change Notification 3-32
Error Checking 3-32
Saving Your Configuration 3-33
Restoring Your Configuration 3-33
CMS Preferences 3-33
Using Different Versions of CMS 3-34
Where to Go Next 3-34
CHAPTER 4Assigning the Switch IP Address and Default Gateway 4-1
Understanding the Boot Process 4-1
Assigning Switch Information 4-2
Default Switch Information 4-3
Understanding DHCP-Based Autoconfiguration 4-3
DHCP Client Request Process 4-4
Configuring the DHCP Server 4-5
Configuring the TFTP Server 4-5
Configuring the DNS 4-6
Configuring the Relay Device 4-6
Obtaining Configuration Files 4-7

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Example Configuration 4-8
Manually Assigning IP Information 4-10
Checking and Saving the Running Configuration 4-10
CHAPTER 5Configuring IE2100 CNS Agents 5-1
Understanding IE2100 Series Configuration Registrar Software 5-1
CNS Configuration Service 5-2
CNS Event Service 5-3
NameSpace Mapper 5-3
What You Should Know About ConfigID, DeviceID, and Host Name 5-3
ConfigID 5-3
DeviceID 5-4
Host Name and DeviceID 5-4
Using Host Name, DeviceID, and ConfigID 5-4
Understanding CNS Embedded Agents 5-5
Initial Configuration 5-5
Incremental (Partial) Configuration 5-6
Synchronized Configuration 5-6
Configuring CNS Embedded Agents 5-6
Enabling Automated CNS Configuration 5-6
Enabling the CNS Event Agent 5-8
Enabling the CNS Configuration Agent 5-9
Enabling an Initial Configuration 5-9
Enabling a Partial Configuration 5-12
Displaying CNS Configuration 5-13
CHAPTER 6Clustering Switches 6-1
Understanding Switch Clusters 6-2
Command Switch Characteristics 6-3
Standby Command Switch Characteristics 6-3
Candidate Switch and Member Switch Characteristics 6-4
Planning a Switch Cluster 6-5
Automatic Discovery of Cluster Candidates and Members 6-5
Discovery through CDP Hops 6-6
Discovery through Non-CDP-Capable and Noncluster-Capable Devices 6-7
Discovery through the Same Management VLAN 6-8
Discovery through Different Management VLANs 6-9
Discovery of Newly Installed Switches 6-10
HSRP and Standby Command Switches 6-12

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Virtual IP Addresses 6-13
Other Considerations for Cluster Standby Groups 6-13
Automatic Recovery of Cluster Configuration 6-15
IP Addresses 6-15
Host Names 6-16
Passwords 6-16
SNMP Community Strings 6-16
TACACS+ and RADIUS 6-17
Access Modes in CMS 6-17
ManagementVLAN 6-18
LRE Profiles 6-18
Availability of Switch-Specific Features in Switch Clusters 6-19
Creating a Switch Cluster 6-19
Enabling a Command Switch 6-19
Adding Member Switches 6-20
Creating a Cluster Standby Group 6-22
Verifying a Switch Cluster 6-24
Using the CLI to Manage Switch Clusters 6-25
Catalyst 1900 and Catalyst 2820 CLI Considerations 6-25
Using SNMP to Manage Switch Clusters 6-26
CHAPTER 7Administering the Switch 7-1
Preventing Unauthorized Access to Your Switch 7-1
Protecting Access to Privileged EXEC Commands 7-2
Default Password and Privilege Level Configuration 7-2
Setting or Changing a Static Enable Password 7-3
Protecting Enable and Enable Secret Passwords with Encryption 7-4
Disabling Password Recovery 7-5
Setting a Telnet Password for a Terminal Line 7-6
Configuring Username and Password Pairs 7-7
Configuring Multiple Privilege Levels 7-8
Setting the Privilege Level for a Command 7-8
Changing the Default Privilege Level for Lines 7-9
Logging into and Exiting a Privilege Level 7-10
Controlling Switch Access with TACACS+ 7-10
Understanding TACACS+ 7-10
TACACS+ Operation 7-12
Configuring TACACS+ 7-12
Default TACACS+ Configuration 7-13

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Identifying the TACACS+ Server Host and Setting the Authentication Key 7-13
Configuring TACACS+ Login Authentication 7-14
Configuring TACACS+ Authorization for Privileged EXEC Access and Network Services 7-16
Starting TACACS+ Accounting 7-17
Displaying the TACACS+ Configuration 7-17
Controlling Switch Access with RADIUS 7-18
Understanding RADIUS 7-18
RADIUS Operation 7-19
Configuring RADIUS 7-20
Default RADIUS Configuration 7-20
Identifying the RADIUS Server Host 7-20
Configuring RADIUS Login Authentication 7-23
Defining AAA Server Groups 7-25
Configuring RADIUS Authorization for User Privileged Access and Network Services 7-27
Starting RADIUS Accounting 7-28
Configuring Settings for All RADIUS Servers 7-29
Configuring the Switch to Use Vendor-Specific RADIUS Attributes 7-29
Configuring the Switch for Vendor-Proprietary RADIUS Server Communication 7-30
Displaying the RADIUS Configuration 7-31
Configuring the Switch for Local Authentication and Authorization 7-32
Configuring the Switch for Secure Shell 7-33
Understanding SSH 7-33
Configuring SSH 7-33
Managing the System Time and Date 7-34
Understanding the System Clock 7-34
Understanding Network Time Protocol 7-34
Configuring NTP 7-36
Default NTP Configuration 7-37
Configuring NTP Authentication 7-37
Configuring NTP Associations 7-38
Configuring NTP Broadcast Service 7-39
Configuring NTP Access Restrictions 7-40
Configuring the Source IP Address for NTP Packets 7-42
Displaying the NTP Configuration 7-43
Configuring Time and Date Manually 7-43
Setting the System Clock 7-44
Displaying the Time and Date Configuration 7-44
Configuring the TimeZone 7-45
Configuring Summer Time (Daylight Saving Time) 7-46

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Configuring a System Nameand Prompt 7-48
Default System Name and Prompt Configuration 7-48
Configuring a System Name 7-48
Configuring a System Prompt 7-49
Understanding DNS 7-49
Default DNS Configuration 7-50
Setting Up DNS 7-50
Displaying the DNS Configuration 7-51
Creating a Banner 7-51
Default Banner Configuration 7-51
Configuring a Message-of-the-Day Login Banner 7-52
Configuring a Login Banner 7-53
Managing the MAC Address Table 7-54
Building the Address Table 7-54
MAC Addresses and VLANs 7-55
Default MAC Address Table Configuration 7-55
Changing the Address Aging Time 7-55
Removing Dynamic Address Entries 7-56
Configuring MAC Address Notification Traps 7-56
Adding and Removing Static Address Entries 7-58
Adding and Removing Secure Addresses 7-59
Displaying Address Table Entries 7-60
Managing the ARP Table 7-61
Switch Software Releases 7-61
CHAPTER 8Configuring 802.1X Port-Based Authentication 8-1
Understanding 802.1X Port-Based Authentication 8-1
Device Roles 8-2
Authentication Initiation and Message Exchange 8-3
Ports in Authorized and Unauthorized States 8-4
Supported Topologies 8-5
Configuring 802.1X Authentication 8-5
Default 802.1X Configuration 8-6
802.1X Configuration Guidelines 8-7
Enabling 802.1X Authentication 8-8
Configuring the Switch-to-RADIUS-ServerCommunication 8-9
Enabling Periodic Re-Authentication 8-10
Manually Re-Authenticating a Client Connected to a Port 8-11
Changing the Quiet Period 8-11

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Changing the Switch-to-Client Retransmission Time 8-12
Setting the Switch-to-Client Frame-Retransmission Number 8-13
Enabling Multiple Hosts 8-13
Resetting the 802.1X Configuration to the Default Values 8-14
Displaying 802.1X Statisticsand Status 8-14
CHAPTER 9Configuring the Switch Interfaces 9-1
Understanding Interface Types 9-1
Access Ports 9-2
Trunk Ports 9-2
Port-Based VLANs 9-3
EtherChannelPort Groups 9-3
Connecting Interfaces 9-3
Using the Interface Command 9-4
Procedures for Configuring Interfaces 9-4
Configuring a Range of Interfaces 9-6
Configuring and Using Interface-Range Macros 9-8
Configuring Switch Interfaces 9-9
Default Ethernet Interface Configuration 9-10
SFP Configuration 9-10
Configuring Interface Speed and Duplex Mode 9-11
ConfigurationGuidelines 9-12
Setting the Interface Speed and Duplex Parameters 9-13
Configuring Media Types for Gigabit Interfaces 9-14
Configuring IEEE 802.3X Flow Control on Gigabit Ethernet Ports 9-14
Adding a Description foran Interface 9-16
Monitoring and Maintaining the Interfaces 9-16
Monitoring Interface and ControllerStatus 9-16
Clearing and Resetting Interfaces and Counters 9-19
Shutting Down and Restarting the Interface 9-19
CHAPTER 10 Configuring LRE 10-1
Ports on the 2950 LRE 10-1
LRE Links and LRE Profiles 10-2
LRE Profiles 10-2
LRE Sequences 10-4
CPE Ethernet Links 10-5
Configuring LRE Ports 10-5
Environmental Guidelines for LRE Links 10-6