Cisco 2975 - Catalyst LAN Base Switch User manual

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Catalyst 2975 Switch Software
Configuration Guide
Cisco IOS Release 12.2(55)SE
August 2010
Text Part Number: OL-19720-02

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Catalyst 2975 Switch Software Configuration Guide
© 2009–2010 Cisco Systems, Inc. All rights reserved.

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CONTENTS
Preface xxxv
Audience xxxv
Purpose xxxv
Conventions xxxvi
Related Publications xxxvi
Obtaining Documentation, Obtaining Support, and Security Guidelines xxxvii
CHAPTER 1Overview 1-1
Features 1-1
Ease-of-Deployment and Ease-of-Use Features 1-2
Performance Features 1-3
Management Options 1-5
Manageability Features 1-5
Availability and Redundancy Features 1-7
VLAN Features 1-8
Security Features 1-8
QoS and CoS Features 1-11
Layer 3 Features 1-12
Power over Ethernet Features 1-12
Monitoring Features 1-12
Default Settings After Initial Switch Configuration 1-13
Network Configuration Examples 1-15
Design Concepts for Using the Switch 1-15
Small to Medium-Sized Network Using Catalyst 2975 Switches 1-19
Long-Distance, High-Bandwidth Transport Configuration 1-20
Where to Go Next 1-21
CHAPTER 2Using the Command-Line Interface 2-1
Understanding Command Modes 2-1
Understanding the Help System 2-3
Understanding Abbreviated Commands 2-4
Understanding no and default Forms of Commands 2-4
Understanding CLI Error Messages 2-5

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Using Configuration Logging 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 through a Console Connection or through Telnet 2-10
CHAPTER 3Assigning the Switch IP Address and Default Gateway 3-1
Understanding the Boot Process 3-2
Assigning Switch Information 3-3
Default Switch Information 3-3
Understanding DHCP-Based Autoconfiguration 3-4
DHCP Client Request Process 3-4
Understanding DHCP-based Autoconfiguration and Image Update 3-5
DHCP Autoconfiguration 3-5
DHCP Auto-Image Update 3-6
Limitations and Restrictions 3-6
Configuring DHCP-Based Autoconfiguration 3-7
DHCP Server Configuration Guidelines 3-7
Configuring the TFTP Server 3-8
Configuring the DNS 3-8
Configuring the Relay Device 3-9
Obtaining Configuration Files 3-9
Example Configuration 3-10
Configuring the DHCP Auto Configuration and Image Update Features 3-12
Configuring DHCP Autoconfiguration (Only Configuration File) 3-12
Configuring DHCP Auto-Image Update (Configuration File and Image) 3-13
Configuring the Client 3-14
Manually Assigning IP Information 3-15
Checking and Saving the Running Configuration 3-16
Configuring the NVRAM Buffer Size 3-17

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Modifying the Startup Configuration 3-18
Default Boot Configuration 3-18
Automatically Downloading a Configuration File 3-18
Specifying the Filename to Read and Write the System Configuration 3-19
Booting Manually 3-19
Booting a Specific Software Image 3-20
Controlling Environment Variables 3-21
Scheduling a Reload of the Software Image 3-23
Configuring a Scheduled Reload 3-23
Displaying Scheduled Reload Information 3-24
CHAPTER 4Configuring Cisco IOS Configuration Engine 4-1
Understanding Cisco Configuration Engine Software 4-1
Configuration Service 4-2
Event Service 4-3
NameSpace Mapper 4-3
What You Should Know About the CNS IDs and Device Hostnames 4-3
ConfigID 4-3
DeviceID 4-4
Hostname and DeviceID 4-4
Using Hostname, DeviceID, and ConfigID 4-4
Understanding Cisco IOS Agents 4-5
Initial Configuration 4-5
Incremental (Partial) Configuration 4-6
Synchronized Configuration 4-6
Configuring Cisco IOS Agents 4-6
Enabling Automated CNS Configuration 4-6
Enabling the CNS Event Agent 4-7
Enabling the Cisco IOS CNS Agent 4-9
Enabling an Initial Configuration 4-9
Enabling a Partial Configuration 4-12
Displaying CNS Configuration 4-13
CHAPTER 5Clustering Switches 5-1
Understanding Switch Clusters 5-1
Cluster Command Switch Characteristics 5-3
Standby Cluster Command Switch Characteristics 5-3
Candidate Switch and Cluster Member Switch Characteristics 5-4

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Planning a Switch Cluster 5-5
Automatic Discovery of Cluster Candidates and Members 5-5
Discovery Through CDP Hops 5-5
Discovery Through Non-CDP-Capable and Noncluster-Capable Devices 5-7
Discovery Through Different VLANs 5-7
Discovery Through Different Management VLANs 5-8
Discovery of Newly Installed Switches 5-9
HSRP and Standby Cluster Command Switches 5-10
Virtual IP Addresses 5-11
Other Considerations for Cluster Standby Groups 5-11
Automatic Recovery of Cluster Configuration 5-12
IP Addresses 5-13
Hostnames 5-13
Passwords 5-14
SNMP Community Strings 5-14
Switch Clusters and Switch Stacks 5-14
TACACS+ and RADIUS 5-16
LRE Profiles 5-16
Using the CLI to Manage Switch Clusters 5-16
Using SNMP to Manage Switch Clusters 5-17
CHAPTER 6Managing Switch Stacks 6-1
Understanding Stacks 6-1
Stack Membership 6-3
Master Election 6-4
Stack MAC Address 6-5
Member Numbers 6-6
Member Priority Values 6-6
Stack Offline Configuration 6-7
Effects of Adding a Provisioned Switch to a Stack 6-7
Effects of Replacing a Provisioned Switch in a Stack 6-9
Effects of Removing a Provisioned Switch from a Stack 6-9
Stack Software Compatibility Recommendations 6-9
Stack Protocol Version Compatibility 6-9
Major Version Number Incompatibility Among Switches 6-9
Minor Version Number Incompatibility Among Switches 6-9
Understanding Auto-Upgrade and Auto-Advise 6-10
Auto-Upgrade and Auto-Advise Example Messages 6-11
Incompatible Software and Member Image Upgrades 6-13

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Stack Configuration Files 6-13
Additional Considerations for System-Wide Configuration on Switch Stacks 6-13
Stack Management Connectivity 6-14
Stack Through an IP Address 6-14
Stack Through an SSH Session 6-14
Stack Through Console Ports 6-15
Specific Members 6-15
Stack Configuration Scenarios 6-15
Configuring the Switch Stack 6-17
Default Switch Stack Configuration 6-17
Enabling Persistent MAC Address 6-17
Assigning Stack Member Information 6-19
Assigning a Member Number 6-19
Setting the Member Priority Value 6-20
Provisioning a New Member for a Stack 6-20
Changing the Stack Membership 6-21
Accessing the CLI of a Specific Member 6-22
Displaying Stack Information 6-22
Troubleshooting Stacks 6-23
Manually Disabling a Stack Port 6-23
Re-Enabling a Stack Port While Another Member Starts 6-23
Understanding the show switch stack-ports summary Output 6-24
Identifying Loopback Problems 6-25
Software Loopback 6-25
Software Loopback Example: No Connected Stack Cable 6-26
Software Loopback Examples: Connected Stack Cables 6-26
Hardware Loopback 6-27
Hardware Loopback Example: LINK OK event 6-27
Hardware Loop Example: LINK NOT OK Event 6-28
Finding a Disconnected StackWiseStackCable 6-28
Fixing a Bad Connection Between Stack Ports 6-29
CHAPTER 7Administering the Switch 7-1
Managing the System Time and Date 7-1
Understanding the System Clock 7-1
Understanding Network Time Protocol 7-2

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Configuring NTP 7-4
Default NTP Configuration 7-4
Configuring NTP Authentication 7-5
Configuring NTP Associations 7-6
Configuring NTP Broadcast Service 7-7
Configuring NTP Access Restrictions 7-8
Configuring the Source IP Address for NTP Packets 7-10
Displaying the NTP Configuration 7-11
Configuring Time and Date Manually 7-11
Setting the System Clock 7-11
Displaying the Time and Date Configuration 7-12
Configuring the Time Zone 7-12
Configuring Summer Time (Daylight Saving Time) 7-13
Configuring a System Name and Prompt 7-14
Default System Name and Prompt Configuration 7-15
Configuring a System Name 7-15
Understanding DNS 7-15
Default DNS Configuration 7-16
Setting Up DNS 7-16
Displaying the DNS Configuration 7-17
Creating a Banner 7-17
Default Banner Configuration 7-17
Configuring a Message-of-the-Day Login Banner 7-18
Configuring a Login Banner 7-19
Managing the MAC Address Table 7-19
Building the Address Table 7-20
MAC Addresses and VLANs 7-20
MAC Addresses and Switch Stacks 7-21
Default MAC Address Table Configuration 7-21
Changing the Address Aging Time 7-21
Removing Dynamic Address Entries 7-22
Configuring MAC Address Change Notification Traps 7-22
Configuring MAC Address Move Notification Traps 7-24
Configuring MAC Threshold Notification Traps 7-25
Adding and Removing Static Address Entries 7-26
Configuring Unicast MAC Address Filtering 7-27
Disabling MAC Address Learning on a VLAN 7-28
Displaying Address Table Entries 7-30
Managing the ARP Table 7-30

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CHAPTER 8Configuring SDM Templates 8-1
Understanding the SDM Templates 8-1
SDM Templates and Switch Stacks 8-2
Configuring the Switch SDM Template 8-3
Default SDM Template 8-3
SDM Template Configuration Guidelines 8-3
Setting the SDM Template 8-4
.Displaying the SDM Templates 8-4
CHAPTER 9Configuring Switch-Based Authentication 9-1
Preventing Unauthorized Access to Your Switch 9-1
Protecting Access to Privileged EXEC Commands 9-2
Default Password and Privilege Level Configuration 9-3
Setting or Changing a Static Enable Password 9-3
Protecting Enable and Enable Secret Passwords with Encryption 9-4
Disabling Password Recovery 9-5
Setting a Telnet Password for a Terminal Line 9-6
Configuring Username and Password Pairs 9-7
Configuring Multiple Privilege Levels 9-8
Setting the Privilege Level for a Command 9-8
Changing the Default Privilege Level for Lines 9-9
Logging into and Exiting a Privilege Level 9-10
Controlling Switch Access with TACACS+ 9-10
Understanding TACACS+ 9-10
TACACS+ Operation 9-12
Configuring TACACS+ 9-13
Default TACACS+ Configuration 9-13
Identifying the TACACS+ Server Host and Setting the Authentication Key 9-13
Configuring TACACS+ Login Authentication 9-14
Configuring TACACS+ Authorization for Privileged EXEC Access and Network Services 9-16
Starting TACACS+ Accounting 9-17
Establishing a Session with a Router if the AAA Server is Unreachable 9-18
Displaying the TACACS+ Configuration 9-18
Controlling Switch Access with RADIUS 9-18
Understanding RADIUS 9-18
RADIUS Operation 9-20
RADIUS Change of Authorization 9-20
Overview 9-20
Change-of-Authorization Requests 9-21

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CoA Request Response Code 9-22
CoA Request Commands 9-23
Stacking Guidelines for Session Termination 9-26
Configuring RADIUS 9-27
Default RADIUS Configuration 9-27
Identifying the RADIUS Server Host 9-28
Configuring RADIUS Login Authentication 9-30
Defining AAA Server Groups 9-32
Configuring RADIUS Authorization for User Privileged Access and Network Services 9-34
Starting RADIUS Accounting 9-35
Establishing a Session with a Router if the AAA Server is Unreachable 9-36
Configuring Settings for All RADIUS Servers 9-36
Configuring the Switch to Use Vendor-Specific RADIUS Attributes 9-36
Configuring the Switch for Vendor-Proprietary RADIUS Server Communication 9-38
Configuring CoA on the Switch 9-39
Monitoring and Troubleshooting CoA Functionality 9-40
Configuring RADIUS Server Load Balancing 9-40
Displaying the RADIUS Configuration 9-40
Configuring the Switch for Local Authentication and Authorization 9-40
Configuring the Switch for Secure Shell 9-41
Understanding SSH 9-42
SSH Servers, Integrated Clients, and Supported Versions 9-42
Limitations 9-43
Configuring SSH 9-43
Configuration Guidelines 9-43
Setting Up the Switch to Run SSH 9-43
Configuring the SSH Server 9-44
Displaying the SSH Configuration and Status 9-45
Configuring the Switch for Secure Socket Layer HTTP 9-46
Understanding Secure HTTP Servers and Clients 9-46
Certificate Authority Trustpoints 9-46
CipherSuites 9-48
Configuring Secure HTTP Servers and Clients 9-48
Default SSL Configuration 9-48
SSL Configuration Guidelines 9-49
Configuring a CA Trustpoint 9-49
Configuring the Secure HTTP Server 9-50
Configuring the Secure HTTP Client 9-51
Displaying Secure HTTP Server and Client Status 9-52