Cisco Catalyst 2928 User manual

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Catalyst 2928 Switch
Software Configuration Guide
Cisco IOS Release 12.2(55)EZ
November 2010
Text Part Number: OL-23389-01

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Catalyst 2928 Switch Software Configuration Guide
©2010 Cisco Systems, Inc. All rights reserved.

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CONTENTS
Preface xxvii
Audience xxvii
Purpose xxvii
Conventions xxvii
Related Publications xxviii
Obtaining Documentation, Obtaining Support, and Security Guidelines xxix
CHAPTER 1Overview 1-1
Features 1-1
Ease-of-Deployment and Ease-of-Use Features 1-1
Performance Features 1-2
Management Options 1-3
Manageability Features 1-4
Availability and Redundancy Features 1-5
VLAN Features 1-5
Security Features 1-6
QoS and CoS Features 1-7
Power over Ethernet Features (WS-C2928-24LT-C only) 1-7
Monitoring Features 1-8
Default Settings After Initial Switch Configuration 1-8
Network Configuration Examples 1-11
Design Concepts for Using the Switch 1-11
Small to Medium-Sized Network Using Catalyst 2928 Switches 1-14
Campus Network Using Catalyst 2928 Switches 1-15
Where to Go Next 1-16
CHAPTER 2Using the Command-Line Interface 2-1
Understanding Command Modes 2-1
Understanding the Help System 2-3
Understanding Abbreviated Commands 2-3
Understanding no and default Forms of Commands 2-4
Understanding CLI Error Messages 2-4
Using Configuration Logging 2-4

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Using Command History 2-5
Changing the Command History Buffer Size 2-5
Recalling Commands 2-6
Disabling the Command History Feature 2-6
Using Editing Features 2-6
Enabling and Disabling Editing Features 2-6
Editing Commands through Keystrokes 2-7
Editing Command Lines that Wrap 2-8
Searching and Filtering Output of show and more Commands 2-9
Accessing the CLI 2-9
Accessing the CLI through a Console Connection or through Telnet 2-9
CHAPTER 3Assigning the Switch IP Address and Default Gateway 3-1
Understanding the Boot Process 3-1
Assigning Switch Information 3-2
Default Switch Information 3-3
Understanding DHCP-Based Autoconfiguration 3-3
DHCP Client Request Process 3-4
Understanding DHCP-based Autoconfiguration and Image Update 3-4
DHCP Autoconfiguration 3-5
DHCP Auto-Image Update 3-5
Limitations and Restrictions 3-5
Configuring DHCP-Based Autoconfiguration 3-6
DHCP Server Configuration Guidelines 3-6
Configuring the TFTP Server 3-7
Configuring the DNS 3-7
Configuring the Relay Device 3-7
Obtaining Configuration Files 3-8
Example Configuration 3-9
Configuring the DHCP Auto Configuration and Image Update Features 3-11
Configuring DHCP Autoconfiguration (Only Configuration File) 3-11
Configuring DHCP Auto-Image Update (Configuration File and Image) 3-12
Configuring the Client 3-13
Manually Assigning IP Information 3-14
Checking and Saving the Running Configuration 3-14
Modifying the Startup Configuration 3-15
Default Boot Configuration 3-16
Automatically Downloading a Configuration File 3-16
Specifying the Filename to Read and Write the System Configuration 3-16

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Booting Manually 3-17
Booting a Specific Software Image 3-18
Controlling Environment Variables 3-18
Scheduling a Reload of the Software Image 3-20
Configuring a Scheduled Reload 3-20
Displaying Scheduled Reload Information 3-21
CHAPTER 4Configuring Cisco IOS CNS Agents 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 4-8
Enabling an Initial Configuration 4-9
Enabling a Partial Configuration 4-11
Displaying CNS Configuration 4-12
CHAPTER 5Clustering Switches 5-1
Understanding Switch Clusters 5-1
Cluster Command Switch Characteristics 5-2
Standby Cluster Command Switch Characteristics 5-3
Candidate Switch and Cluster Member Switch Characteristics 5-3
Planning a Switch Cluster 5-4
Automatic Discovery of Cluster Candidates and Members 5-4
Discovery Through CDP Hops 5-4
Discovery Through Non-CDP-Capable and Noncluster-Capable Devices 5-5
Discovery Through Different VLANs 5-6

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Discovery Through Different Management VLANs 5-7
Discovery of Newly Installed Switches 5-8
HSRP and Standby Cluster Command Switches 5-9
Virtual IP Addresses 5-10
Other Considerations for Cluster Standby Groups 5-10
Automatic Recovery of Cluster Configuration 5-11
IP Addresses 5-12
Hostnames 5-12
Passwords 5-12
SNMP Community Strings 5-13
TACACS+ and RADIUS 5-13
LRE Profiles 5-13
Using the CLI to Manage Switch Clusters 5-13
Catalyst 1900 and Catalyst 2820 CLI Considerations 5-14
Using SNMP to Manage Switch Clusters 5-14
CHAPTER 6Configuring SDM Templates 6-1
Understanding the SDM Templates 6-1
Configuring the Switch SDM Template 6-2
Default SDM Template 6-2
SDM Template Configuration Guidelines 6-2
Displaying the SDM Templates 6-3
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
Configuring NTP 7-4
Default NTP Configuration 7-4
Configuring NTP Authentication 7-4
Configuring NTP Associations 7-5
Configuring NTP Broadcast Service 7-6
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

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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 7-17
Configuring a Login Banner 7-18
Managing the MAC Address Table 7-19
Building the Address Table 7-20
MAC Addresses and VLANs 7-20
Default MAC Address Table Configuration 7-20
Changing the Address Aging Time 7-20
Removing Dynamic Address Entries 7-21
Configuring MAC Address Notification Traps 7-21
Adding and Removing Static Address Entries 7-23
Configuring Unicast MAC Address Filtering 7-24
Displaying Address Table Entries 7-26
Managing the ARP Table 7-26
CHAPTER 8Configuring Switch-Based Authentication 8-1
Preventing Unauthorized Access to Your Switch 8-1
Protecting Access to Privileged EXEC Commands 8-2
Default Password and Privilege Level Configuration 8-2
Setting or Changing a Static Enable Password 8-3
Protecting Enable and Enable Secret Passwords with Encryption 8-3
Disabling Password Recovery 8-5
Setting a Telnet Password for a Terminal Line 8-6
Configuring Username and Password Pairs 8-6
Configuring Multiple Privilege Levels 8-7
Setting the Privilege Level for a Command 8-8
Changing the Default Privilege Level for Lines 8-9
Logging into and Exiting a Privilege Level 8-9

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Controlling Switch Access with TACACS+ 8-10
Understanding TACACS+ 8-10
TACACS+ Operation 8-12
Configuring TACACS+ 8-12
Default TACACS+ Configuration 8-13
Identifying the TACACS+ Server Host and Setting the Authentication Key 8-13
Configuring TACACS+ Login Authentication 8-14
Configuring TACACS+ Authorization for Privileged EXEC Access and Network Services 8-16
Starting TACACS+ Accounting 8-17
Displaying the TACACS+ Configuration 8-17
Controlling Switch Access with RADIUS 8-17
Understanding RADIUS 8-18
RADIUS Operation 8-19
Configuring RADIUS 8-20
Default RADIUS Configuration 8-20
Identifying the RADIUS Server Host 8-20
Configuring RADIUS Login Authentication 8-23
Defining AAA Server Groups 8-25
Configuring RADIUS Authorization for User Privileged Access and Network Services 8-27
Starting RADIUS Accounting 8-28
Configuring Settings for All RADIUS Servers 8-29
Configuring the Switch to Use Vendor-Specific RADIUS Attributes 8-29
Configuring the Switch for Vendor-Proprietary RADIUS Server Communication 8-31
Displaying the RADIUS Configuration 8-31
Configuring the Switch for Local Authentication and Authorization 8-32
Configuring the Switch for Secure Shell 8-33
Understanding SSH 8-33
SSH Servers, Integrated Clients, and Supported Versions 8-33
Limitations 8-34
Configuring SSH 8-34
Configuration Guidelines 8-34
Setting Up the Switch to Run SSH 8-35
Configuring the SSH Server 8-36
Displaying the SSH Configuration and Status 8-36
Configuring the Switch for Secure Socket Layer HTTP 8-37
Understanding Secure HTTP Servers and Clients 8-37
Certificate Authority Trustpoints 8-37
CipherSuites 8-39

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Configuring Secure HTTP Servers and Clients 8-39
Default SSL Configuration 8-39
SSL Configuration Guidelines 8-40
Configuring a CA Trustpoint 8-40
Configuring the Secure HTTP Server 8-41
Configuring the Secure HTTP Client 8-42
Displaying Secure HTTP Server and Client Status 8-43
Configuring the Switch for Secure Copy Protocol 8-43
Information About Secure Copy 8-44
CHAPTER 9Configuring IEEE 802.1x Port-Based Authentication 9-1
Understanding IEEE 802.1x Port-Based Authentication 9-1
Device Roles 9-2
Authentication Process 9-3
Authentication Initiation and Message Exchange 9-5
Ports in Authorized and Unauthorized States 9-7
IEEE 802.1x Host Mode 9-7
IEEE 802.1x Accounting 9-8
IEEE 802.1x Accounting Attribute-Value Pairs 9-8
Using IEEE 802.1x Authentication with VLAN Assignment 9-9
Using IEEE 802.1x Authentication with Guest VLAN 9-11
Using IEEE 802.1x Authentication with Restricted VLAN 9-12
Using IEEE 802.1x Authentication with Voice VLAN Ports 9-13
Using IEEE 802.1x Authentication with Port Security 9-13
Using IEEE 802.1x Authentication with MAC Authentication Bypass 9-14
802.1x Authentication with Restricted VLAN 9-15
Common Session ID 9-16
Configuring IEEE 802.1x Authentication 9-17
Default IEEE 802.1x Authentication Configuration 9-17
IEEE 802.1x Authentication Configuration Guidelines 9-19
IEEE 802.1x Authentication 9-19
VLAN Assignment and Guest VLAN 9-20
MAC Authentication Bypass 9-20
Upgrading from a Previous Software Release 9-20
Configuring IEEE 802.1x Authentication 9-20
Configuring the Switch-to-RADIUS-Server Communication 9-22
Configuring the Host Mode 9-23
Configuring Periodic Re-Authentication 9-24
Manually Re-Authenticating a Client Connected to a Port 9-24

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Changing the Quiet Period 9-25
Changing the Switch-to-Client Retransmission Time 9-25
Setting the Switch-to-Client Frame-Retransmission Number 9-26
Setting the Re-Authentication Number 9-27
Configuring IEEE 802.1x Accounting 9-27
Configuring a Guest VLAN 9-28
Configuring a Restricted VLAN 9-29
Configuring MAC Authentication Bypass 9-31
Disabling IEEE 802.1x Authentication on the Port 9-31
Resetting the IEEE 802.1x Authentication Configuration to the Default Values 9-32
Displaying IEEE 802.1x Statistics and Status 9-32
CHAPTER 10 Configuring Web-Based Authentication 10-1
Understanding Web-Based Authentication 10-1
Device Roles 10-2
Host Detection 10-2
Session Creation 10-3
Authentication Process 10-3
Local Web Authentication Banner 10-4
Web Authentication Customizable Web Pages 10-6
Guidelines 10-6
Web-based Authentication Interactions with Other Features 10-7
Port Security 10-7
LAN Port IP 10-8
Gateway IP 10-8
ACLs 10-8
Context-Based Access Control 10-8
802.1x Authentication 10-8
EtherChannel 10-8
Configuring Web-Based Authentication 10-9
Default Web-Based Authentication Configuration 10-9
Web-Based Authentication Configuration Guidelines and Restrictions 10-9
Web-Based Authentication Configuration Task List 10-10
Configuring the Authentication Rule and Interfaces 10-10
Configuring AAA Authentication 10-11
Configuring Switch-to-RADIUS-Server Communication 10-11
Configuring the HTTP Server 10-13
Customizing the Authentication Proxy Web Pages 10-13
Specifying a Redirection URL for Successful Login 10-15