Spanning Tree and Redundant Connectivity

Chapter 18 Configuring STP

Understanding Spanning-Tree Features

Spanning Tree and Redundant Connectivity

You can create a redundant backbone with spanning tree by connecting two switch interfaces to another device or to two different devices, as shown in Figure 18-4. Spanning tree automatically disables one interface but enables it if the other one fails. If one link is high-speed and the other is low-speed, the low-speed link is always disabled. If the speeds are the same, the port priority and port ID are added together, and spanning tree disables the link with the lowest value.

Figure 18-4 Spanning Tree and Redundant Connectivity

Active link

Blocked link

Workstations

101226

You can also create redundant links between switches by using EtherChannel groups. For more information, see Chapter 37, “Configuring EtherChannels and Link-State Tracking.”

Spanning-Tree Address Management

IEEE 802.1D specifies 17 multicast addresses, ranging from 0x00180C2000000 to 0x0180C2000010, to be used by different bridge protocols. These addresses are static addresses that cannot be removed.

Regardless of the spanning-tree state, each switch in the stack receives but does not forward packets destined for addresses between 0x0180C2000000 and 0x0180C200000F.

If spanning tree is enabled, the CPU on the switch or on each switch in the stack receives packets destined for 0x0180C2000000 and 0x0180C2000010. If spanning tree is disabled, the switch or each switch in the stack forwards those packets as unknown multicast addresses.

Accelerated Aging to Retain Connectivity

The default for aging dynamic addresses is 5 minutes, the default setting of the mac address-tableaging-timeglobal configuration command. However, a spanning-tree reconfiguration can cause many station locations to change. Because these stations could be unreachable for 5 minutes or more during a reconfiguration, the address-aging time is accelerated so that station addresses can be dropped from the address table and then relearned. The accelerated aging is the same as the forward-delay parameter value (spanning-tree vlan vlan-idforward-timeseconds global configuration command) when the spanning tree reconfigures.

Catalyst 3750-E and 3560-E Switch Software Configuration Guide

	OL-9775-02	18-9

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Image 445

Cisco Systems 3750E manual Spanning Tree and Redundant Connectivity, Spanning-Tree Address Management, 18-9

Contents

Text Part Number OL-9775-02 Americas HeadquartersPage Iii N T E N T S Assigning the Switch IP Address and Default Gateway Understanding Cisco Configuration Engine Software Clustering Switches Vii Catalyst 1900 and Catalyst 2820 CLI Considerations Viii Creating a Banner Changing the Default Privilege Level for Lines Device Roles Bypass Xii Routed Ports Xiii Monitoring and Maintaining the Interfaces Xiv Encapsulation Types Domain Names Xvi Private-VLAN Configuration Guidelines Xvii Disabled State Xviii Boundary Ports 19-25 Xix Dhcp Server Xxi Configuring Dynamic ARP Inspection Xxii Configuring MVR Xxiii Understanding Storm Control Xxiv Understanding Udld Modes of Operation Xxv Creating an Rspan Source Session Xxvi Snmp Agent Functions Xxvii Creating a Numbered Extended ACL Xxviii Interaction with Other Features and Switches Xxix Xxx Port-Channel Interfaces Xxxi Configuring IP Addressing Xxxii Nonstop Forwarding Awareness Xxxiii IPv6 Addresses Xxxiv Configuring Hsrp Priority Xxxv Configuring IP Multicast Routing Xxxvi Configuring Basic Dvmrp Interoperability Features Xxxvii Using a Filter 45-14 Xxxviii Xxxix Configuring Online Diagnostics Unsupported Route-Map Configuration Commands C-1 Xli Hsrp Xlii VTP Audience PrefacePurpose Conventions Xliv Related Publications Xlv Xlvi Overview Features Availability and Redundancy Features, Vlan Features, Deployment Features Overview Features Performance Features Management Options Manageability Features Availability and Redundancy Features Security Features Vlan Features Overview Features QoS and CoS Features Layer 3 Features Power over Ethernet Features Monitoring Features Default Settings After Initial Switch ConfigurationVlan Overview Default Settings After Initial Switch Configuration Overview Default Settings After Initial Switch Configuration Design Concepts for Using the Switch Network Configuration Examples Network Demands Suggested Design Methods Cost-Effective Wiring Closet High-Performance Wiring Closet High-Performance Workgroup Gigabit-to-the-Desktop Redundant Gigabit Backbone Server Aggregation Linux Server Cluster Cisco SoftPhone Software Gigabit servers Internet Cisco 2600 or 3700 routers Catalyst 3560-E switches Large Network Using Catalyst 3750-E and 3560-E Switches Cisco 7x00 routers Catalyst Catalyst 3560-E Multidwelling Network Using Catalyst 3750-E Switches 11 Catalyst 3750-E Switches in a MAN Configuration Long-Distance, High-Bandwidth Transport Configuration Access layer Aggregation layer Where to Go Next OL-9775-02 Understanding Command Modes Using the Command-Line Interface Configure Mode Access Method Prompt Exit Method About This ModeQuit Ctrl-Z Command Purpose Console commandUnderstanding the Help System Line vty or line Understanding no and default Forms of Commands Understanding Abbreviated CommandsCommand ? Command keyword ? Using Configuration Logging Understanding CLI Error MessagesError Message Meaning How to Get Help Changing the Command History Buffer Size Using Command HistoryRecalling Commands Action1 Result Disabling the Command History Feature Using Editing FeaturesEnabling and Disabling Editing Features Switch# terminal editing Capability Keystroke1 Purpose Editing Commands through Keystrokes Return and Space bar Editing Command Lines that WrapPress Ctrl-L or Ctrl-R Command begin include exclude regular-expression Accessing the CLISwitch# show interfaces include protocol Using the Command-Line Interface Accessing the CLI OL-9775-02 Understanding the Boot Process Assigning the Switch IP Address and Default Gateway Assigning Switch Information Understanding DHCP-Based Autoconfiguration Default Switch InformationFeature Default Setting Dhcp Client and Server Message Exchange Dhcp Client Request Process Dhcp Server Configuration Guidelines Configuring DHCP-Based Autoconfiguration Configuring the DNS Configuring the Tftp Server Obtaining Configuration Files Configuring the Relay DeviceRouterconfig-if#ip helper-address Tftpserver Example Configuration DNS Server Configuration Switch a Switch B Switch C Switch DTftp Server Configuration on Unix Dhcp Client Configuration Manually Assigning IP Information Switch# show running-config Checking and Saving the Running ConfigurationSwitch# copy running-config startup-config Default Boot Configuration Modifying the Startup ConfigurationAutomatically Downloading a Configuration File Boot config-file flash/ file-url Booting ManuallyShow boot Configure terminal Enter global configuration mode Boot system filesystem /file-url Booting a Specific Software Image Controlling Environment Variables Boot system switch number all Set Switchnumber Set Manualboot yes Boot manualSwitch current-stack-member-number renumber Set Switchpriority Scheduling a Reload of the Software Image Configuring a Scheduled ReloadVariable Description Reload in hhmm text Switch# reload at 0200 jun Switch# reload atDisplaying Scheduled Reload Information Understanding Cisco Configuration Engine Software Configuring Cisco IOS CNS Agents Configuration Engine Architectural Overview Configuration Service ConfigID Event ServiceWhat You Should Know About the CNS IDs and Device Hostnames NameSpace Mapper DeviceID Using Hostname, DeviceID, and ConfigIDHostname and DeviceID Understanding Cisco IOS Agents Initial Configuration Incremental Partial Configuration Configuring Cisco IOS AgentsSynchronized Configuration Enabling Automated CNS Configuration Device Required Configuration Show running-config Backup init-retry retry-count keepalive secondsEnabling the CNS Event Agent Show cns event connections Enabling the Cisco IOS CNS Agent Enabling an Initial Configuration Cns id interface num dns-reverse ipaddress Cns config initial ip-address hostnameMac-address event Cns id hardware-serial hostname string string Show running-config Verify your entries Enabling a Partial ConfigurationCns config partial ip-address hostname Show cns config stats Show cns config connections Displaying CNS ConfigurationShow cns event stats Show cns event subject Understanding Switch Stacks Managing Switch Stacks Managing Switch Stacks Understanding Switch Stacks Switch Stack Membership Creating a Switch Stack from Two Standalone Switches Stack Master Election and Re-Election Adding a Standalone Switch to a Switch Stack Stack Member Numbers Switch Stack Bridge ID and Router MAC Address Stack Member Priority Values Effects of Adding a Provisioned Switch to a Switch Stack Switch Stack Offline ConfigurationScenario Result Scenario Result Effects of Replacing a Provisioned Switch in a Switch Stack Switch Stack Software Compatibility Recommendations Minor Version Number Incompatibility Among Switches Major Version Number Incompatibility Among SwitchesStack Protocol Version Compatibility Understanding Auto-Upgrade and Auto-Advise Switch Auto-Upgrade and Auto-Advise Example MessagesDirectory Mar 1 000422.537%IMAGEMGR-6-AUTOADVISESW Switch Stack Configuration Files Incompatible Software and Stack Member Image Upgrades Switch Stack Management Connectivity Connectivity to the Switch Stack Through an SSH Session Connectivity to the Switch Stack Through an IP AddressConnectivity to Specific Stack Members Use the switch stack-member-number Switch Stack Configuration ScenariosPriority new-priority-number global Current-stack-member-number Renumber new-stack-member-number Default Switch Stack Configuration Configuring the Switch StackEnabling Persistent MAC Address Show switch Stack-mac persistent timerSwitchconfig# stack-mac persistent timer Time-value Assigning Stack Member Information Setting the Stack Member Priority ValueAssigning a Stack Member Number Provisioning a New Member for a Switch Stack Displaying Switch Stack Information Accessing the CLI of a Specific Stack MemberCommand Description Show switch stack-member-number Show switch stack-ring activity Show switch stack-portsDetail OL-9775-02 Understanding Switch Clusters Clustering Switches Switch Cisco IOS Release Cluster Capability Standby Cluster Command Switch Characteristics Cluster Command Switch Characteristics Candidate Switch and Cluster Member Switch Characteristics Planning a Switch Cluster Discovery Through CDP Hops Automatic Discovery of Cluster Candidates and Members Discovery Through CDP Hops Discovery Through Different VLANs Discovery Through Different VLANs Discovery Through Different Management VLANs Discovery Through Routed Ports New out-of-box Discovery of Newly Installed Switches Hsrp and Standby Cluster Command Switches Other Considerations for Cluster Standby Groups Virtual IP Addresses Automatic Recovery of Cluster Configuration Hostnames IP Addresses Snmp Community Strings Passwords Switch Stack Switch Cluster Switch Clusters and Switch StacksMembers Other cluster member switches LRE Profiles TACACS+ and Radius Switch# rcommand Using the CLI to Manage Switch ClustersCatalyst 1900 and Catalyst 2820 CLI Considerations Snmp Management for a Cluster Using Snmp to Manage Switch Clusters OL-9775-02 Managing the System Time and Date Administering the SwitchUnderstanding the System Clock NTP Understanding Network Time Protocol Typical NTP Network Configuration Configuring NTP Configuring NTP Authentication Default NTP ConfigurationNtp authenticate Configuring NTP Associations Switchconfig# ntp server 172.16.22.44 version Configuring NTP Broadcast ServiceNtp peer ip-address version number Key keyid source interface prefer Ntp broadcast version number key keyid Interface interface-idDestination-address Ntp broadcast client Ntp broadcastdelay microseconds Configuring NTP Access RestrictionsNtp access-group query-only Serve-onl y serve peer Command Purpose Interface interface-id Configuring the Source IP Address for NTP Packets Displaying the NTP Configuration Configuring Time and Date ManuallySetting the System Clock Fundamentals Command Reference, Release Configuring the Time Zone Displaying the Time and Date ConfigurationClock timezone zone hours-offset Minutes-offset Clock summer-time zone recurring Configuring Summer Time Daylight Saving TimeWeek day month hh mm week day month Hh mm offset Clock summer-time zone date month Configuring a System Name and PromptClock summer-time zone date date Configuring a System Name Default System Name and Prompt ConfigurationCopy running-config startup-confi g Understanding DNS Setting Up DNS Default DNS ConfigurationIp domain-name name Ip name-server server-address1 Displaying the DNS Configuration Default Banner ConfigurationCreating a Banner Banner motd c message c Configuring a Message-of-the-Day Login BannerUnix telnet Banner login c message c Configuring a Login BannerManaging the MAC Address Table MAC Addresses and VLANs Building the Address Table Default MAC Address Table Configuration MAC Addresses and Switch StacksChanging the Address Aging Time Removing Dynamic Address Entries Configuring MAC Address Notification TrapsMac address-table aging-time Show mac address-table aging-time Snmp-server enable traps mac-notification String by using the snmp-server communitySnmp-server host host-addr traps informs version Mac address-table notification Adding and Removing Static Address Entries Mac address-table static mac-addr Configuring Unicast MAC Address FilteringVlan vlan-id interface interface-id Show mac address-table static Vlan vlan-id drop Displaying Address Table Entries Managing the ARP Table OL-9775-02 Understanding the SDM Templates Configuring SDM Templates Dual IPv4 and IPv6 SDM Templates Resource Access Default Routing IPv4-and-IPv6 Resource Default Routing SDM Templates and Switch Stacks Default SDM Template Configuring the Switch SDM TemplateSDM Template Configuration Guidelines Sdm prefer access default Setting the SDM TemplateDual-ipv4-and-ipv6 default routing Vlan routing vlan Switchconfig# sdm prefer dual-ipv4-and-ipv6 default Switchconfig# sdm prefer routingDisplaying the SDM Templates Policy based routing aces 25K OL-9775-02 Preventing Unauthorized Access to Your Switch Configuring Switch-Based Authentication Default Password and Privilege Level Configuration Protecting Access to Privileged Exec Commands Enable password password Setting or Changing a Static Enable PasswordSwitchconfig# enable password l1u2c3k4y5 Encryption-type encrypted-password Enable password level level passwordEnable secret level level password Service password-encryption No service password-recovery Disabling Password RecoveryShow version Configuring Username and Password Pairs Setting a Telnet Password for a Terminal LinePassword password Switchconfig-line#password let45me67in89 Username command Configuring Multiple Privilege LevelsLogin local Username name privilege level Privilege mode level level command Setting the Privilege Level for a CommandShow privilege Command Changing the Default Privilege Level for LinesLogging into and Exiting a Privilege Level Understanding TACACS+ Controlling Switch Access with TACACS+ Typical TACACS+ Network Configuration TACACS+ Operation Configuring TACACS+ Tacacs-server host hostname port Default TACACS+ ConfigurationAaa new-model Aaa group server tacacs+ group-name Aaa new-model Enable AAA Configuring TACACS+ Login AuthenticationShow tacacs Verify your entries Login authentication default Aaa authentication login defaultAuthentication login command Line console tty vty line-number Show running-config Verify your entries Displaying the TACACS+ Configuration Controlling Switch Access with RadiusStarting TACACS+ Accounting Understanding Radius Radius Operation Transitioning from Radius to TACACS+ Services Default Radius Configuration Configuring RadiusIdentifying the Radius Server Host Page Radius-server host hostname Acct-port port-number timeoutIp-address auth-port port-number Seconds retransmit retries key Switchconfig# radius-server host host1 Configuring Radius Login Authentication Server Host section on Defining AAA Server Groups Aaa group server radius group-name Radius Aaa authorization network radius Starting Radius Accounting Radius-server timeout seconds Configuring Settings for All Radius ServersRadius-server key string Radius-server retransmit retries Radius-server vsa send accounting AuthenticationCisco-avpair=shellpriv-lvl=15 Cisco-avpair=ipoutacl#2=deny ip 10.10.10.10 0.0.255.255 any Displaying the Radius Configuration Controlling Switch Access with KerberosRadius-server host hostname ip-address non-standard Understanding Kerberos KDC Term Definition Kerberos Operation Authenticating to a Boundary SwitchKeytab Srvtab Authenticating to Network Services Configuring KerberosObtaining a TGT from a KDC Aaa authorization exec local Aaa authentication login default localAaa authorization network local Username command Configuring the Switch for Secure ShellUsername name privilege level SSH Servers, Integrated Clients, and Supported Versions Understanding SSH Configuration Guidelines Configuring SSHLimitations Setting Up the Switch to Run SSH Configuring the SSH Server Displaying the SSH Configuration and StatusIp ssh timeout seconds Authentication-retries number Understanding Secure Http Servers and Clients Configuring the Switch for Secure Socket Layer HttpCertificate Authority Trustpoints Rsakeypair TP-self-signed-3080755072 Default SSL Configuration Configuring Secure Http Servers and ClientsCipherSuites Configuring a CA Trustpoint SSL Configuration Guidelines Configuring the Secure Http Server Ip http timeout-policy idle seconds life Configuring the Secure Http ClientShow ip http server secure status Ip http client secure-trustpoint name Displaying Secure Http Server and Client Status Configuring the Switch for Secure Copy ProtocolIp http client secure-ciphersuite Show ip http client secure status Html Information About Secure Copy OL-9775-02 Understanding Ieee 802.1x Port-Based Authentication Configuring Ieee 802.1x Port-Based Authentication10-1 10-2 Device Roles 10-3 Authentication Process 10-4 Authentication Flowchart 10-5 Authentication Initiation and Message Exchange EAPOL-Start 10-6 Ports in Authorized and Unauthorized States Ieee 802.1x Authentication and Switch Stacks10-7 10-8 Ieee 802.1x Host Mode Ieee 802.1x Accounting Attribute-Value Pairs Ieee 802.1x AccountingAttribute Number AV Pair Name 10-9 10-10 Using Ieee 802.1x Authentication with Vlan Assignment 10-11 Using Ieee 802.1x Authentication with Per-User ACLs 10-12 Using Ieee 802.1x Authentication with Guest Vlan 10-13 Using Ieee 802.1x Authentication with Restricted Vlan 10-14 10-15 Using Ieee 802.1x Authentication with Voice Vlan Ports 10-16 Using Ieee 802.1x Authentication with Port Security 10-17 Using Ieee 802.1x Authentication with Wake-on-LAN 10-18 Network Admission Control Layer 2 Ieee 802.1x Validation Using Multidomain Authentication10-19 For example Using Web Authentication10-20 10-21 Configuring Ieee 802.1x Authentication AAA Default Ieee 802.1x Authentication Configuration10-22 Ieee 802.1x Authentication Ieee 802.1x Authentication Configuration Guidelines10-23 10-24 MAC Authentication Bypass Configuring Ieee 802.1x Authentication10-25 10-26 Configuring the Switch-to-RADIUS-Server Communication 10-27 Ip-address auth-port port-number key Dot1x host-mode multi-host Configuring the Host ModeMulti-domain Show dot1x interface interface-id Manually Re-Authenticating a Client Connected to a Port Configuring Periodic Re-Authentication10-29 Dot1x timeout tx-period seconds Changing the Switch-to-Client Retransmission TimeChanging the Quiet Period Show dot1x interface interface-id Verify your entries Switchconfig-if#dot1x timeout tx-period Setting the Switch-to-Client Frame-Retransmission NumberShow dot1xinterface interface-id Verify your entries Dot1x max-reauth-req count Configuring Ieee 802.1x Accounting Setting the Re-Authentication NumberSwitchconfig-if#dot1x max-reauth-req 10-32 10-33 Configuring a Guest Vlan Switchport mode private-vlan host Configuring a Restricted VlanSwitchconfig# interface gigabitethernet2/0/2 Dot1x guest-vlan vlan-id Dot1x auth-fail max-attempts max Dot1x auth-fail vlan vlan-idAttempts 10-35 Switchconfig-if#dot1x auth-fail max-attempts Configuring the Inaccessible Authentication Bypass FeatureRadius-server dead-criteria time time Tries tries 10-37 Dot1x critical recovery action Configuring Ieee 802.1x Authentication with WoLReinitialize vlan vlan-id Show dot1x interface interface-id Switchconfig-if#dot1x control-direction both Configuring MAC Authentication BypassSwitchconfig-if#dot1x mac-auth-bypass Dot1x control-direction both 10-40 Configuring NAC Layer 2 Ieee 802.1x Validation 10-41 Configuring Web Authentication 10-42 No dot1x pae Disable Ieee 802.1x authentication on the port Disabling Ieee 802.1x Authentication on the PortDot1x fallback fallback-profile 10-43 10-44 Displaying Ieee 802.1x Statistics and Status Understanding Interface Types Configuring Interface Characteristics11-1 Port-Based VLANs Switch Ports11-2 Trunk Ports Access Ports11-3 Tunnel Ports Routed Ports11-4 EtherChannel Port Groups Switch Virtual Interfaces11-5 Gigabit Ethernet Interfaces Power over Ethernet PortsSupported Protocols and Standards 11-6 Class Powered-Device Detection and Initial Power Allocation11-7 11-8 Power Management Modes 11-9 Power Monitoring and Power Policing 11-10 Maximum Power Allocation Cutoff Power on a PoE Port 11-11 Connecting Interfaces 11-12 Ethernet Management Port 11-13 Connecting a Switch Stack to a PC 11-14 Tftp Mgmtinit Using Interface Configuration ModeMgmtshow Mgmtclr 11-16 Procedures for Configuring Interfaces Interface range port-range macro Configuring a Range of InterfacesMacroname Show interfaces interface-id 11-18 Show running-config include define Configuring and Using Interface Range MacrosDefine interface-range macroname Interface range macro macroname Switch# show running-config include define Configuring Ethernet InterfacesSwitch# show run include define 11-20 11-21 Default Ethernet Interface Configuration Speed and Duplex Configuration Guidelines Configuring Interface Speed and Duplex Mode11-22 Speed 10 100 1000 auto 10 Setting the Interface Speed and Duplex ParametersNonegotiate Duplex auto full half Flowcontrol receive on off desired Configuring Ieee 802.3x Flow Control11-24 Local Side Auto-MDIX Configuring Auto-MDIX on an InterfaceWith Correct Cabling 11-25 Interface-id phy Configuring a Power Management Mode on a PoE Port11-26 Power inline auto max max-wattage Budgeting Power for Devices Connected to a PoE PortShow power inline i nterface-id Neve r static max max-wattage 11-28 Wattage 11-29 Configuring Power Policing 11-30 Adding a Description for an Interface Configuring Ethernet Management Ports Configuring Layer 3 InterfacesSwitch# show interfaces gigabitethernet1/0/2 description 11-31 Interface gigabitethernet interface-id vlan vlan-id No switchportNo shutdown 11-32 11-33 Configuring the System MTU System mtu jumbo bytes Use the system mtu jumbo Use the system mtu routingSystem mtu routing bytes 11-34 System mtu bytes Configuring the Cisco Redundant Power SystemReload Show system mtu Power rps switch-number port rps-port-id mode active Power rps switch-number name string serialnumberStandby 11-36 Power supply switch-numberoff on Configuring the Power SuppliesShow env power Show env rps Monitoring Interface Status Monitoring and Maintaining the Interfaces11-38 11-39 Clearing and Resetting Interfaces and Counters Interface vlan vlan-id gigabitethernet interface-id Shutting Down and Restarting the InterfaceShutdown 11-40 Understanding Smartports Macros Configuring Smartports Macros12-1 Default Smartports Macro Configuration Configuring Smartports MacrosMacro Name Description 12-2 12-3 Smartports Macro Configuration Guidelines Macro name macro-name Creating Smartports MacrosName Sample-Macro and macro name sample-macro will result Show parser macro name macro-name 12-5 Applying Smartports Macros Show parser macro Applying Cisco-Default Smartports MacrosShow parser macro macro-name 12-6 Switchconfig-if#macro apply cisco-desktop $AVID Switch# show parser macro cisco-desktop12-7 Show parser macro brief Displaying Smartports MacrosShow parser macro description interface 12-8 Understanding VLANs Configuring VLANs13-1 13-2 Vlan Port Membership Modes Supported VLANs13-3 13-4 Configuring Normal-Range VLANs 13-5 Vlan ID Token Ring VLANs Normal-Range Vlan Configuration Guidelines13-6 Saving Vlan Configuration Vlan Configuration Mode OptionsVlan Configuration in config-vlan Mode Vlan Configuration in Vlan Database Configuration Mode Parameter Default Range Default Ethernet Vlan ConfigurationVLANxxxx, where 13-8 Creating or Modifying an Ethernet Vlan Copy running-config startup configRemote-span 13-9 Vlan database Deleting a Vlan13-10 Switchport access vlan vlan-id Assigning Static-Access Ports to a VlanNo vlan vlan-id Show vlan brief Default Vlan Configuration Configuring Extended-Range VLANsShow interfaces interface-id switchport Vlan fields of the display 13-13 Extended-Range Vlan Configuration Guidelines Creating an Extended-Range Vlan Vtp mode transparentShow vlan id vlan-id 13-14 Switch# copy running-config startup config Switchconfig# vtp mode transparentCreating an Extended-Range Vlan with an Internal Vlan ID Show vlan internal usage Command Command Mode Purpose Configuring Vlan TrunksDisplaying VLANs Trunking Overview 13-17 Switches in an ISL Trunking Environment Encapsulation Types Mode FunctionEncapsulation Function 13-18 Configuring an Ethernet Interface as a Trunk Port Default Layer 2 Ethernet Interface Vlan ConfigurationIeee 802.1Q Configuration Considerations 13-19 Configuring a Trunk Port Interaction with Other FeaturesDot1q negotiate 13-20 13-21 Defining the Allowed VLANs on a Trunk Changing the Pruning-Eligible List Switchport trunk allowed vlan addAll except remove vlan-list 13-22 Switchport trunk pruning vlan add Configuring the Native Vlan for Untagged TrafficExcept none remove vlan-list Vlan ,vlan Load Sharing Using STP Port Priorities Configuring Trunk Ports for Load SharingSwitchport trunk native vlan vlan-id 13-24 13-25 Or switch stack Load Sharing Using STP Path CostConnect to the trunk ports configured on Switch a Exit Return to global configuration mode Interface gigabitethernet1/0/1 Switchport trunk encapsulationIsl dot1q negotiate Spanning-tree vlan 2-4 cost Understanding Vmps Configuring Vmps13-28 Vmps Configuration Guidelines Default Vmps Client ConfigurationDynamic-Access Port Vlan Membership 13-29 Entering the IP Address of the Vmps Configuring the Vmps Client13-30 Switchport access vlan dynamic Configuring Dynamic-Access Ports on Vmps ClientsReconfirming Vlan Memberships Vmps reconfirm Changing the Retry Count Changing the Reconfirmation IntervalVmps reconfirm minutes 13-32 Vmps Configuration Example Troubleshooting Dynamic-Access Port Vlan MembershipSwitch# show vmps Monitoring the Vmps 13-34 Dynamic Port Vlan Membership Configuration Understanding VTP Configuring VTP14-1 14-2 VTP Domain VTP Modes VTP Mode DescriptionVTP Advertisements 14-3 VTP Pruning VTP Version14-4 Vlan 14-5 VTP and Switch Stacks Configuring VTP14-6 VTP Configuration Options Default VTP ConfigurationVTP Configuration in Global Configuration Mode 14-7 VTP Configuration in Vlan Database Configuration Mode VTP Configuration GuidelinesPasswords Domain Names Configuration Requirements Configuring a VTP ServerVTP Version 14-9 Vtp password password Vtp password passwordShow vtp status Vtp server Vtp mode client Configuring a VTP ClientSwitch# vlan database 14-11 14-12 Disabling VTP VTP Transparent Mode Vtp version Enabling VTP Version14-13 Enabling VTP Pruning Adding a VTP Client Switch to a VTP DomainVtp pruning 14-14 14-15 14-16 Monitoring VTP Understanding Voice Vlan Configuring Voice Vlan15-1 Cisco IP Phone Data Traffic Cisco IP Phone Voice Traffic15-2 Default Voice Vlan Configuration Configuring Voice VlanVoice Vlan Configuration Guidelines 15-3 15-4 Configuring a Port Connected to a Cisco 7960 IP Phone 15-5 Configuring Cisco IP Phone Voice Traffic 15-6 Configuring the Priority of Incoming Data Frames 15-7 Displaying Voice Vlan 15-8 Understanding Private VLANs Configuring Private VLANs16-1 Private-VLAN Domain 16-2 16-3 IP Addressing Scheme with Private VLANs Private-VLAN Interaction with Other Features Private VLANs across Multiple Switches16-4 Private VLANs and SVIs Private VLANs and Unicast, Broadcast, and Multicast Traffic16-5 Tasks for Configuring Private VLANs Configuring Private VLANsPrivate VLANs and Switch Stacks 16-6 Private-VLAN Configuration Guidelines Default Private-VLAN ConfigurationSecondary and Primary Vlan Configuration 16-7 16-8 Private-VLAN Port Configuration 16-9 Limitations with Other Features 16-10 Configuring and Associating VLANs in a Private Vlan Show interfaces status Show vlan private-vlan type16-11 Switchport private-vlan host-association Configuring a Layer 2 Interface as a Private-VLAN Host PortSwitch# show interfaces gigabitethernet1/0/22 switchport Primaryvlanid secondaryvlanid Switchport private-vlan mapping primaryvlanid Switchport mode private-vlan promiscuousAdd remove secondaryvlanlist 16-13 Interface vlan primaryvlanid Switch# show interfaces private-vlan mappingPrivate-vlan mapping add remove Show interface private-vlan mapping 16-15 Monitoring Private VLANs 16-16 Understanding Ieee 802.1Q Tunneling Configuring Ieee 802.1Q and Layer 2 Protocol Tunneling17-1 17-2 Ieee 802.1Q Tunnel Ports in a Service-Provider Network 17-3 Default Ieee 802.1Q Tunneling Configuration Configuring Ieee 802.1Q TunnelingIeee 802.1Q Tunneling Configuration Guidelines Native VLANs 17-5 System MTU 17-6 Ieee 802.1Q Tunneling and Other Features Vlan dot1q tag native Configuring an Ieee 802.1Q Tunneling PortShow dot1q-tunnel Show vlan dot1q tag native 17-8 Understanding Layer 2 Protocol Tunneling Layer 2 Protocol Tunneling 17-9 17-10 Configuring Layer 2 Protocol Tunneling 17-11 Default Layer 2 Protocol Tunneling Configuration 17-12 Layer 2 Protocol Tunneling Configuration Guidelines 17-13 Configuring Layer 2 Protocol Tunneling Configuring the SP Edge Switch Configuring Layer 2 Tunneling for EtherChannelsL2protocol-tunnel point-to-point Pagp lacp udld 17-15 17-16 Configuring the Customer Switch Switchconfig# interface port-channel Switchconfig-if#channel-group 1 mode desirable17-17 17-18 Monitoring and Maintaining Tunneling Status Understanding Spanning-Tree Features Configuring STP18-1 18-2 STP Overview 18-3 Spanning-Tree Topology and BPDUs 18-4 Bridge ID, Switch Priority, and Extended System ID Spanning-Tree Interface States Switch Priority ValueBit 32768 16384 8192 4096 2048 1024 512 256 128 18-6 2illustrates how an interface moves through the states Listening State Blocking StateLearning State Forwarding State Disabled State How a Switch or Port Becomes the Root Switch or Root Port18-8 Spanning-Tree Address Management Spanning Tree and Redundant ConnectivityAccelerated Aging to Retain Connectivity 18-9 Supported Spanning-Tree Instances Spanning-Tree Modes and Protocols18-10 STP and Ieee 802.1Q Trunks Spanning-Tree Interoperability and Backward CompatibilityVLAN-Bridge Spanning Tree Rapid PVST+ Spanning Tree and Switch Stacks Configuring Spanning-Tree Features18-12 Spanning-Tree Configuration Guidelines Default Spanning-Tree Configuration18-13 18-14 18-15 Changing the Spanning-Tree Mode Disabling Spanning Tree Configuring the Root SwitchShow spanning-tree vlan vlan-id Verify your entries 18-16 Diameter net-diameter hello-time seconds Spanning-tree vlan vlan-id root primaryShow spanning-tree detail 18-17 Configuring Port Priority Configuring a Secondary Root SwitchSpanning-tree vlan vlan-id root secondary Diameter net-diameter hello-time Spanning-tree vlan vlan-id port-priority priority Spanning-tree port-priority priorityShow spanning-tree interface interface-id Show spanning-tree vlan vlan-id Port-channel-number Configuring Path CostSpanning-tree cost cost Spanning-tree vlan vlan-id cost cost Spanning-tree vlan vlan-id priority priority Configuring the Switch Priority of a Vlan18-21 Configuring the Hello Time Configuring Spanning-Tree TimersSpanning-tree vlan vlan-id hello-time seconds 18-22 Configuring the Maximum-Aging Time for a Vlan Configuring the Forwarding-Delay Time for a VlanSpanning-tree vlan vlan-id forward-time Spanning-tree vlan vlan-idmax-age seconds Displaying the Spanning-Tree Status Configuring the Transmit Hold-CountShow spanning-tree detail Verify your entries 18-24 19-1 Configuring Mstp Multiple Spanning-Tree Regions Understanding Mstp19-2 Operations Within an MST Region IST, CIST, and CST19-3 19-4 Operations Between MST Regions Ieee 802.1s Terminology Hop CountCisco Prestandard Cisco Standard 19-5 Ieee 802.1s Implementation Boundary Ports19-6 Port Role Naming Change Interoperation Between Legacy and Standard Switches19-7 Detecting Unidirectional Link Failure Mstp and Switch Stacks19-8 Interoperability with Ieee 802.1D STP Understanding RstpPort Roles and the Active Topology 19-9 19-10 Rapid Convergence 19-11 Synchronization of Port Roles Bit Function Bridge Protocol Data Unit Format and Processing19-12 Processing Superior Bpdu Information Topology ChangesProcessing Inferior Bpdu Information 19-13 19-14 Configuring Mstp Features Mstp Configuration Guidelines Default Mstp Configuration19-15 Spanning-tree mst configuration Specifying the MST Region Configuration and Enabling MstpInstance instance-id vlan vlan-range Name name Revision version Spanning-tree mode mstShow pending Exit 19-18 Spanning-tree mst instance-id root primary 19-19 Show spanning-tree mst interface interface-id Spanning-tree mst instance-id port-priority priority19-20 19-21 Spanning-tree mst instance-id cost cost Configuring the Hello Time Configuring the Switch PrioritySpanning-tree mst instance-id priority priority 19-22 Show spanning-tree mst Verify your entries Configuring the Forwarding-Delay TimeSpanning-tree mst forward-time seconds Show spanning-tree mst Configuring the Maximum-Hop Count Configuring the Maximum-Aging TimeSpecifying the Link Type to Ensure Rapid Transitions Spanning-tree mst max-age seconds 19-25 Designating the Neighbor Type Restarting the Protocol Migration Process Displaying the MST Configuration and Status19-26 Understanding Optional Spanning-Tree Features Configuring Optional Spanning-Tree Features20-1 Understanding Bpdu Guard Understanding Port Fast20-2 Understanding UplinkFast Understanding Bpdu Filtering20-3 20-4 Switches in a Hierarchical Network 20-5 Understanding Cross-Stack UplinkFast 20-6 How Csuf Works Events that Cause Fast Convergence Understanding BackboneFast20-7 BackboneFast Example Before Indirect Link Failure 20-8 20-9 Adding a Switch in a Shared-Medium Topology Understanding Root Guard Understanding EtherChannel Guard20-10 20-11 Understanding Loop Guard Optional Spanning-Tree Configuration Guidelines Default Optional Spanning-Tree ConfigurationEnabling Port Fast 20-12 Enabling Bpdu Guard Spanning-tree portfast trunk interface configurationSpanning-tree portfast trunk Portfast Enabling Bpdu Filtering Spanning-tree portfast Enable the Port Fast feature20-14 20-15 Enabling UplinkFast for Use with Redundant Links Uplinkfast command Spanning-tree uplinkfast max-update-rateEnabling Cross-Stack UplinkFast Enabling BackboneFast Enabling EtherChannel Guard Spanning-tree backbonefast Enable BackboneFastShow spanning-tree summary Verify your entries 20-17 Enabling Loop Guard Enabling Root Guard20-18 20-19 20-20 21-1 Flex Links Vlan Flex Link Load Balancing and Support Switchport backup interface preemption delay commands21-2 21-3 MAC Address-Table Move Update 21-4 MAC Address-Table Move Update Example Default Configuration Configuration Guidelines21-5 Switchport backup interface interface-id Configuring Flex LinksShow interface interface-id switchport backup Switch# show interface switchport backup Mode forced bandwidth off Switchport backup interface interface-id preemptionDelay delay-time 21-7 Switchport backup interface interface-id prefer vlan Configuring Vlan Load Balancing on Flex LinksShow interfaces interface-id switchport backup Switch#show interfaces switchport backup Switchport backup interface interface-idmmu Configuring the MAC Address-Table Move Update FeaturePrimary vlan vlan-id 21-9 Switchconf# mac address-table move update transmit End Return to global configuration modeSwitch# show mac-address-table move update 21-10 21-11 Monitoring Flex Links and the MAC Address-Table Move Update 21-12 Understanding Dhcp Features Configuring Dhcp Features and IP Source Guard22-1 Dhcp Relay Agent Dhcp ServerDhcp Snooping 22-2 22-3 Option-82 Data Insertion Dhcp Relay Agent in a Metropolitan Ethernet Network 22-4 22-5 Remote ID Suboption Frame Format Dhcp Snooping Binding Database Cisco IOS Dhcp Server DatabaseRelease 22-6 22-7 Dhcp Snooping and Switch Stacks Configuring Dhcp FeaturesDefault Dhcp Configuration 22-8 22-9 Dhcp Snooping Configuration Guidelines Dhcp Server and Switch Stacks Configuring the Dhcp Server22-10 Specifying the Packet Forwarding Address Configuring the Dhcp Relay AgentIp helper-address address 22-11 Switchport access vlan vlan-id Switchport mode accessEnabling Dhcp Snooping and Option Interface range port-range 22-13 Enabling the Cisco IOS Dhcp Server Database Enabling Dhcp Snooping on Private VLANsEnabling the Dhcp Snooping Binding Database Agent Ip dhcp snooping database 22-15 Displaying Dhcp Snooping Information Source IP Address Filtering Understanding IP Source Guard22-16 Default IP Source Guard Configuration Configuring IP Source GuardIP Source Guard Configuration Guidelines Source IP and MAC Address Filtering 22-18 Enabling IP Source Guard 22-19 Displaying IP Source Guard Information 22-20 Understanding Dynamic ARP Inspection Configuring Dynamic ARP Inspection23-1 ARP Cache Poisoning 23-2 23-3 Interface Trust States and Network Security Relative Priority of ARP ACLs and Dhcp Snooping Entries Rate Limiting of ARP Packets23-4 Default Dynamic ARP Inspection Configuration Configuring Dynamic ARP InspectionLogging of Dropped Packets 23-5 23-6 Dynamic ARP Inspection Configuration Guidelines Show cdp neighbors Configuring Dynamic ARP Inspection in Dhcp EnvironmentsIp arp inspection vlan vlan-range 23-7 23-8 Configuring ARP ACLs for Non-DHCP Environments 23-9 Limiting the Rate of Incoming ARP Packets Show arp access-list acl-nameNo ip arp inspection trust Specified with the ip arp inspection vlan logging 23-11 Performing Validation Checks Ip arp inspection validate Configuring the Log BufferSrc-mac dst-mac ip Show ip arp inspection vlan Number logs number interval Ip arp inspection log-buffer entries23-13 23-14 Displaying Dynamic ARP Inspection Information Show ip arp inspection statistics vlan Clear ip arp inspection statisticsClear ip arp inspection log Show ip arp inspection log 23-16 24-1 Configuring Igmp Snooping and MVR 24-2 Understanding Igmp Snooping Joining a Multicast Group Igmp Versions24-3 24-4 224.1.2.3 24-5 Leaving a Multicast Group Immediate Leave Igmp Configurable-Leave TimerIgmp Report Suppression 24-6 Igmp Snooping and Switch Stacks Configuring Igmp SnoopingDefault Igmp Snooping Configuration PIM-DVMRP Ip igmp snooping vlan vlan-id Enabling or Disabling Igmp Snooping24-8 Ip igmp snooping vlan vlan-id mrouter Setting the Snooping MethodLearn cgmp pim-dvmrp Show ip igmp snooping Show ip igmp snooping mrouter vlan vlan-id Configuring a Multicast Router Port24-10 Enabling Igmp Immediate Leave Configuring a Host Statically to Join a GroupIp igmp snooping vlan vlan-id static ipaddress Show ip igmp snooping groups 24-12 Configuring the Igmp Leave Timer Recovering from Flood Mode Configuring TCN-Related CommandsControlling the Multicast Flooding Time After a TCN Event Count No ip igmp snooping tcn flood Disabling Multicast Flooding During a TCN Event24-14 24-15 Configuring the Igmp Snooping Querier No ip igmp snooping report-suppression Disabling Igmp Report Suppression24-16 24-17 Displaying Igmp Snooping Information 24-18 Understanding Multicast Vlan Registration 24-19 Using MVR in a Multicast Television Application Default MVR Configuration Configuring MVRMVR 24-20 Configuring MVR Global Parameters MVR Configuration Guidelines and LimitationsMvr Enable MVR on the switch 24-21 24-22 Configuring MVR Interfaces Mvr immediate Mvr type source receiverShow mvr Show mvr interface Show mvr members Displaying MVR Information Configuring Igmp Filtering and Throttling24-24 Configuring Igmp Profiles Default Igmp Filtering and Throttling Configuration24-25 Permit deny Ip igmp profile profile numberRange ip multicast address Show ip igmp profile profile number Switch# show ip igmp profile Setting the Maximum Number of Igmp GroupsApplying Igmp Profiles Ip igmp filter profile number Show running-config interface Verify the configuration Configuring the Igmp Throttling ActionEtherChannel group or a EtherChannel interface Interface-id Ip igmp max-groups action deny Displaying Igmp Filtering and Throttling ConfigurationReplace Show ip igmp profile profile 24-30 Understanding MLD Snooping Configuring IPv6 MLD Snooping25-1 25-2 MLD Queries MLD MessagesMulticast Client Aging Robustness 25-3 MLD Reports Multicast Router DiscoveryMLD Done Messages and Immediate-Leave 25-4 MLD Snooping in Switch Stacks Configuring IPv6 MLD SnoopingTopology Change Notification Processing 25-5 MLD Snooping Configuration Guidelines Default MLD Snooping Configuration25-6 Ipv6 mld snooping Enabling or Disabling MLD SnoopingIpv6 mld snooping vlan vlan-id 25-7 Ipv6 mld snooping vlan vlan-id static Configuring a Static Multicast GroupShow ipv6 mld snooping multicast-address user Show ipv6 mld snooping multicast-address vlan Ipv6 mld snooping vlan vlan-id mrouter Enabling MLD Immediate LeaveShow ipv6 mld snooping mrouter vlan vlan-id 25-9 25-10 Configuring MLD Snooping Queries Disabling MLD Listener Message Suppression Displaying MLD Snooping Information25-11 Vlan-id count dynamic user Show ipv6 mld snooping querier vlan vlan-idVlan-id ipv6-multicast-address 25-12 Configuring Storm Control Configuring Port-Based Traffic ControlUnderstanding Storm Control 26-1 Broadcast Storm Control Example 26-2 Configuring Storm Control and Threshold Levels Default Storm Control Configuration26-3 Unicast level level level-low bps bps Storm-control broadcast multicastBps-low pps pps pps-low Storm-control action shutdown trap Default Protected Port Configuration Configuring Protected PortsShow storm-control interface-id broadcast Multicast unicast Protected Port Configuration Guidelines Configuring Port BlockingConfiguring a Protected Port 26-6 Default Port Blocking Configuration Configuring Port SecurityBlocking Flooded Traffic on an Interface 26-7 Secure MAC Addresses Understanding Port Security26-8 26-9 Security Violations Port Security Configuration Guidelines Default Port Security ConfigurationForwarded1 Trap Message Message2 Increments 26-10 26-11 26-12 Enabling and Configuring Port Security Protect restrict shutdown Switchport port-security violationShutdown vlan 26-13 26-14 Switchconfig-if#switchport port-security maximum Switchconfig-if#switchport port-securitySwitchconfig-if#switchport port-security mac-address sticky Switchconfig-if#switchport port-security violation restrict 26-16 Enabling and Configuring Port Security Aging Switchconfig# interface GigabitEthernet 1/0/8 Port Security and Switch StacksPort Security and Private VLANs 26-17 Show port-security interface interface-idaddress Displaying Port-Based Traffic Control SettingsShow port-security interface interface-idvlan 26-18 Understanding CDP Configuring CDP27-1 CDP and Switch Stacks Configuring CDPDefault CDP Configuration Configuring the CDP Characteristics Cdp holdtime seconds Disabling and Enabling CDPCdp advertise-v2 Show cdp Cdp enable Enable CDP on the interface after disabling it No cdp enable Disable CDP on the interfaceDisabling and Enabling CDP on an Interface 27-4 27-5 Monitoring and Maintaining CDP 27-6 Understanding Lldp and LLDP-MED Configuring Lldp and LLDP-MEDUnderstanding Lldp 28-1 28-2 Understanding LLDP-MED Default Lldp Configuration Configuring Lldp and LLDP-MEDConfiguring Lldp Characteristics 28-3 28-4 Disabling and Enabling Lldp Globally 28-5 Disabling and Enabling Lldp on an Interface TLV, and enter interface configuration mode Configuring LLDP-MED TLVsNo lldp med-tlv-select tlv Specify the TLV to disable Lldp med-tlv-select tlv Specify the TLV to enable 28-7 Monitoring and Maintaining Lldp and LLDP-MED 28-8 Understanding Udld Configuring UdldModes of Operation 29-1 29-2 Methods to Detect Unidirectional Links 29-3 Configuring Udld 29-4 Default Udld Configuration Message-timer-interval Udld aggressive enable message timeEnabling Udld Globally Show udld Udld reset Show udld Resetting an Interface Disabled by UdldEnabling Udld on an Interface Udld port aggressive 29-7 Displaying Udld Status 29-8 Understanding Span and Rspan Configuring Span and Rspan30-1 30-2 Local Span 30-3 Remote Span Span Sessions Span and Rspan Concepts and Terminology30-4 30-5 Monitored Traffic 30-6 Source Ports Vlan Filtering Source VLANs30-7 30-8 Destination Port Rspan Vlan Span and Rspan Interaction with Other Features30-9 Span and Rspan and Switch Stacks Configuring Span and Rspan30-10 Configuring Local Span Default Span and Rspan ConfigurationSpan Configuration Guidelines 30-11 30-12 Creating a Local Span Session Destination interface interface-id Monitor session sessionnumberEncapsulation replicate Show monitor session sessionnumber 30-14 Monitor session sessionnumber filter vlan Specifying VLANs to Filter30-15 Rspan Configuration Guidelines Configuring RspanBe a Vlan 30-16 30-17 Configuring a Vlan as an Rspan Vlan Interfaces port-channelport-channel-number. Valid Creating an Rspan Source SessionDestination remote vlan vlan-id 30-18 Remote vlan vlan-id Creating an Rspan Destination Session30-19 30-20 Untagged vlan vlan-id or vlan vlan-id- Forward incoming Ingress dot1q vlan vlan-id isl untagged30-21 30-22 Show monitor session sessionnumber 30-23 Displaying Span and Rspan Status 30-24 Understanding Rmon Configuring Rmon31-1 31-2 Configuring Rmon Configuring Rmon Alarms and Events Default Rmon Configuration31-3 Add an event in the Rmon event table that is Rmon event number description string log owner string31-4 Collecting Group Ethernet Statistics on an Interface Collecting Group History Statistics on an InterfaceRmon collection history index Show rmon history Rmon collection stats index owner ownername Displaying Rmon StatusShow rmon statistics 31-6 Understanding System Message Logging Configuring System Message Logging32-1 System Log Message Format Configuring System Message Logging32-2 Text string that uniquely describes the message Hhmmss short uptime32-3 No logging console Disable message logging Default System Message Logging ConfigurationShow running-config Verify your entries Show logging Disabling Message Logging Logging buffered size Setting the Message Display Destination DeviceLogging host 32-5 Logging file flash filename Synchronizing Log MessagesTerminal monitor Session to see the debugging messages Line vty Line console vty line-numberLogging synchronous level severity-level All limit number-of-buffers Enabling and Disabling Sequence Numbers in Log Messages Enabling and Disabling Time Stamps on Log Messages32-8 Logging console level Defining the Message Severity LevelLogging monitor level Logging trap level 32-10 Level Description Syslog Definition Logging history level Enabling the Configuration-Change LoggerLogging history size number 32-11 Logging Messages to a Unix Syslog Daemon Configuring Unix Syslog Servers32-12 Logging facility facility-type Configuring the Unix System Logging FacilityFacility-type keywords 32-13 Facility Type Keyword Description Displaying the Logging Configuration32-14 Understanding Snmp Configuring Snmp33-1 33-2 Snmp Versions Snmp Manager Functions Model Level Authentication Encryption ResultDES Operation Description Snmp Agent Functions Using Snmp to Access MIB Variables33-4 33-5 Snmp Notifications Snmp ifIndex MIB Object Values Configuring SnmpIfIndex Range SVI Snmp Configuration Guidelines Default Snmp Configuration33-7 No snmp-server Disable the Snmp agent operation Configuring Community StringsDisabling the Snmp Agent 33-8 Access-list access-list-number deny View-name ro rw access-list-numberSnmp-server community string view Permit source source-wildcard Snmp-server engineID local engineid-string Configuring Snmp Groups and UsersSnmp-server engineID local 33-10 Snmp-server group groupname v1 v2c Write writeview notify notifyview accessAuth noauth priv read readview 33-11 Remote host udp-port port v1 access Configuring Snmp NotificationsEncrypted access access-list auth md5 Notification Type Keyword Description 33-13 33-14 33-12 , or enter snmp-server enable traps ? Setting the Agent Contact and Location InformationEnable traps command for each trap type Notification-types Limiting Tftp Servers Used Through Snmp Switchconfig# snmp-server community publicSnmp Examples Snmp-server tftp-server-list 33-17 Displaying Snmp Status 33-18 Understanding ACLs Configuring Network Security with ACLs34-1 34-2 Supported ACLs 34-3 Port ACLs 34-4 Router ACLs Vlan Maps Handling Fragmented and Unfragmented Traffic34-5 34-6 ACLs and Switch Stacks 34-7 Configuring IPv4 ACLs Access List Number Type Supported Access List NumbersCreating Standard and Extended IPv4 ACLs 34-8 34-9 ACL Logging Show access-lists number name Access-list access-list-number deny permitCreating a Numbered Standard ACL Source source-wildcard log 34-11 Creating a Numbered Extended ACL 34-12 34-13 34-14 Creating Named Standard and Extended ACLs Resequencing ACEs in an ACL34-15 Ip access-list extended name Ip access-list standard nameAny log Tos tos established log time-range 34-17 Using Time Ranges with ACLs Periodic weekdays weekend daily Absolute start time dateShow time-range 34-18 Applying an IPv4 ACL to a Terminal Line Switch# show ip access-listsIncluding Comments in ACLs 34-19 Applying an IPv4 ACL to an Interface Access-class access-list-numberOut 34-20 34-21 Ip access-group access-list-number Hardware and Software Treatment of IP ACLs IPv4 ACL Configuration Examples34-22 Switchconfig# access-list 106 permit ip any 172.20.128.64 Switchconfig# access-list 6 permit 172.20.128.6434-23 Extended ACLs Numbered ACLs34-24 Time Range Applied to an IP ACL Named ACLsCommented IP ACL Entries 34-25 Switchconfig-if#ip access-group ext1 Switch# show logging34-26 34-27 Creating Named MAC Extended ACLs 34-28 Applying a MAC ACL to a Layer 2 Interface Mac access-group name Configuring Vlan MapsShow mac access-group interface interface-id ACL 34-30 Vlan Map Configuration Guidelines Creating a Vlan Map Vlan access-map name numberAction drop forward Match ip mac address name 34-32 Examples of ACLs and Vlan Maps 34-33 Wiring Closet Configuration Using Vlan Maps in Your NetworkApplying a Vlan Map to a Vlan Vlan filter mapname vlan-list list Switchconfig# vlan access-map map2 Denying Access to a Server on Anothera VlanSwitchconfig# ip access-list extended matchall Switchconfig# vlan filter map2 vlan 34-36 Using Vlan Maps with Router ACLs 34-37 Vlan Maps and Router ACL Configuration Guidelines Examples of Router ACLs and Vlan Maps Applied to VLANs ACLs and Switched PacketsACLs and Bridged Packets 34-38 34-39 ACLs and Routed Packets Show ip access-lists number name Displaying IPv4 ACL ConfigurationACLs and Multicast Packets 34-40 Show mac access-group interface interface-id Show running-config interface interface-idShow ip interface interface-id 34-41 34-42 35-1 Configuring IPv6 ACLs 35-2 Understanding IPv6 ACLs IPv6 ACLs and Switch Stacks Supported ACL FeaturesIPv6 ACL Limitations 35-3 Default IPv6 ACL Configuration Configuring IPv6 ACLsInteraction with Other Features and Switches 35-4 Creating IPv6 ACLs Ipv6 access-list access-list-name35-5 Log-input routing sequence Dscp value fragments logValue time-range name 35-6 35-7 Applying an IPv6 ACL to an Interface Ipv6 traffic-filter access-list-nameIpv6 address ipv6-address 35-8 Show ipv6 access-list access-list-name Show access-listsDisplaying IPv6 ACLs 35-9 35-10 36-1 Configuring QoS 36-2 Understanding QoS 36-3 Basic QoS Model Basic QoS Model 36-4 36-5 Classification Check if packet came with CoS label tag Yes 36-6 Classification Based on Class Maps and Policy Maps Classification Based on QoS ACLs36-7 36-8 Policing and Marking 36-9 Policing on Physical Ports 36-10 Policing on SVIs 36-11 Policing and Marking Flowchart on SVIs 36-12 Mapping Tables 36-13 Queueing and Scheduling Overview SRR Shaping and Sharing Weighted Tail Drop36-14 36-15 Queueing and Scheduling on Ingress Queues 36-16 Queue Type Function 36-17 WTD Thresholds 36-18 Queueing and Scheduling on Egress Queues 36-19 36-20 Buffer and Memory Allocation 36-21 Packet Modification 36-22 Configuring Auto-QoS 36-23 Generated Auto-QoS Configuration 36-24 Description Automatically Generated Command 36-25 Sizes. It configures the bandwidth and the SRR mode shaped Switch automatically configures the egress queue bufferIf you entered the auto qos voip trust command, the switch Or shared on the egress queues mapped to the port Auto-QoS Configuration Guidelines Effects of Auto-QoS on the Configuration36-27 Auto qos voip cisco-phone Enabling Auto-QoS for VoIPCisco-softphone trust Show auto qos interface interface-id 36-29 36-30 Auto-QoS Configuration Example Debug auto qos Cdp enableAuto qos voip trust Show auto qos Displaying Auto-QoS Information Configuring Standard QoS36-32 Default Ingress Queue Configuration Default Standard QoS Configuration36-33 Dscp Value Queue ID -Threshold ID Default Egress Queue Configuration36-34 Default Mapping Table Configuration Standard QoS Configuration GuidelinesQoS ACL Guidelines Applying QoS on Interfaces General QoS Guidelines Policing Guidelines36-36 Enabling VLAN-Based QoS on Physical Ports Enabling QoS Globally36-37 Configuring the Trust State on Ports within the QoS Domain Configuring Classification Using Port Trust States36-38 15 Port Trusted States within the QoS Domain 36-39 Mls qos trust cos dscp ip-precedence Configuring the CoS Value for an InterfaceShow mls qos interface 36-40 Mls qos cos default-cos override Configuring a Trusted Boundary to Ensure Port Security36-41 Mls qos trust dscp Enabling Dscp Transparency ModeMls qos trust device cisco-phone 36-42 36-43 No mls qos rewrite ip dscp Mls qos dscp-mutation Mls qos map dscp-mutationShow mls qos maps dscp-mutation 36-44 Switchconfig-if#mls qos dscp-mutation gi1/0/2-mutation Configuring a QoS Policy36-45 36-46 Classifying Traffic by Using ACLs Switchconfig# access-list 102 permit pim any 224.0.0.2 dscp Switchconfig# access-list 100 permit ip any any dscpPermit protocol source source-wildcard Source-wildcard 36-48 Mac access-list extended name Class-map match-all match-any Classifying Traffic by Using Class MapsIs match-all Match-any keywords Ip dscp dscp-list ip precedence Match access-group acl-index-or-nameIp-precedence-list Show class-map 36-51 Class class-map-name Policy-map policy-map-name36-52 36-53 Show policy-map policy-map-nameclass Service-policy input policy-map-name36-54 Switchconfig-pmap#class macclass2 maclist2 Switchconfig# policy-map macpolicy1Switchconfig-if#service-policy input macpolicy1 36-55 36-56 Traffic by Using Class Maps section on 36-57 Drop policed-dscp-transmit Police rate-bps burst-byte exceed-actionExceed-action policed-dscp-transmit keywords to mark down 36-58 36-59 Service-policy policy-map-name Show policy-map policy-map-nameclass Service-policy input policy-map-nameShow mls qos vlan-based Aggregate-policer-name rate-bps burst-byte Mls qos aggregate-policerExceed-action drop Policed-dscp-transmit Show mls qos aggregate-policer Only one policy map per ingress port is supportedAggregate-policer-name Configuring the CoS-to-DSCP Map Configuring Dscp MapsSwitchconfig-pmap-c#police aggregate transmit1 CoS Value Dscp Value Mls qos map cos-dscp dscp1...dscp8 Configuring the IP-Precedence-to-DSCP MapIP Precedence Value Dscp Value 36-64 36-65 Configuring the Policed-DSCP Map Dscp Value CoS Value Configuring the DSCP-to-CoS Map36-66 Show Mls qos map dscp-cos dscp-list to cos Configuring the DSCP-to-DSCP-Mutation MapShow mls qos maps dscp-to-cos 36-67 Switch# show mls qos maps dscp-mutation mutation1 Switchconfig-if#mls qos dscp-mutation mutation136-68 36-69 Configuring Ingress Queue Characteristics Mls qos srr-queue input cos-map Mls qos srr-queue input dscp-mapMls qos srr-queue input threshold Show mls qos maps Allocating Bandwidth Between the Ingress Queues Allocating Buffer Space Between the Ingress QueuesMls qos srr-queue input buffers Show mls qos interface buffer Weight1 weight2 Configuring the Ingress Priority QueueMls qos srr-queue input bandwidth Show mls qos interface queueing Weight Configuring Egress Queue CharacteristicsMls qos srr-queue input Priority-queue queue-id bandwidth 36-74 Queue-set qset-id Mls qos queue-set output qset-id36-75 36-76 Mls qos srr-queue output cos-map Mls qos srr-queue output dscp-map36-77 Srr-queue bandwidth shape weight1 Configuring SRR Shaped Weights on Egress QueuesWeight2 weight3 weight4 Queueing Configuring the Egress Expedite Queue Configuring SRR Shared Weights on Egress QueuesSrr-queue bandwidth share weight1 36-79 Srr-queue bandwidth limit weight1 Mls qos Enable QoS on a switchLimiting the Bandwidth on an Egress Interface 36-80 36-81 Displaying Standard QoS Information 36-82 Show running-config include rewrite Understanding EtherChannels Configuring EtherChannels and Link-State Tracking37-1 37-2 EtherChannel Overview 37-3 Single-Switch EtherChannel 37-4 Port-Channel Interfaces 37-5 Port Aggregation Protocol Mode Description PAgP Interaction with Other FeaturesPAgP Modes Auto Link Aggregation Control Protocol Lacp Interaction with Other FeaturesLacp Modes 37-7 Load-Balancing and Forwarding Methods EtherChannel On Mode37-8 37-9 37-10 EtherChannel and Switch Stacks Default EtherChannel Configuration Configuring EtherChannels37-11 37-12 EtherChannel Configuration Guidelines 37-13 Configuring Layer 2 EtherChannels Active passive Auto non-silent desirable non-silent on37-14 Switchconfig-if-range#channel-group 5 mode active Configuring Layer 3 EtherChannelsCreating Port-Channel Logical Interfaces 37-15 Interface port-channel port-channel-number Configuring the Physical InterfacesShow etherchannel channel-group-number detail No ip address For channel-group-number, the range is 1 to 48. This number Partner that is PAgP capable, configure the switch port forMust be the same as the port-channel-number logical port 37-17 Port-channel load-balance dst-ip dst-mac Configuring EtherChannel Load-BalancingSrc-dst-ip src-dst-mac src-ip src-mac 37-18 Show etherchannel load-balance Verify your entries Configuring the PAgP Learn Method and Priority37-19 Pagp learn-method physical-port Configuring Lacp Hot-Standby PortsPagp port-priority priority Show pagp channel-group-number internal Show running-config Verify your entries Show lacp sys-id Configuring the Lacp System Priority37-21 Lacp port-priority priority Configuring the Lacp Port PriorityShow lacp channel-group-number Internal Understanding Link-State Tracking Displaying EtherChannel, PAgP, and Lacp Status37-23 37-24 37-25 Configuring Link-State Tracking Link-State Tracking Configuration Guidelines Default Link-State Tracking ConfigurationConfiguring Link-State Tracking 37-26 Switch show link state group detail Switch show link state groupDisplaying Link-State Tracking Status 37-27 37-28 38-1 Configuring IP Unicast Routing Types of Routing Understanding IP Routing38-2 38-3 IP Routing and Switch Stacks 38-4 Configuring IP Addressing Steps for Configuring Routing38-5 ARP Default Addressing ConfigurationIrdp 38-6 Assigning IP Addresses to Network Interfaces Show running-config Verify your entryUse of Subnet Zero 38-7 38-8 Classless Routing No ip classless Disable classless routing behavior Configuring Address Resolution Methods38-9 Arp ip-address hardware-address type Define a Static ARP Cache38-10 38-11 Set ARP Encapsulation Enable Proxy ARP Routing Assistance When IP Routing is DisabledDefault Gateway Proxy ARP 38-13 Icmp Router Discovery Protocol Irdp 38-14 Configuring Broadcast Packet Handling Ip forward-protocol udp port nd sdns Ip directed-broadcast access-list-number38-15 38-16 Forwarding UDP Broadcast Packets and Protocols Flooding IP Broadcasts Establishing an IP Broadcast AddressIp broadcast-address ip-address 38-17 Clear arp-cache Monitoring and Maintaining IP AddressingClear host name Clear ip route network mask 38-19 Enabling IP Unicast Routing 38-20 Configuring RIP Configuring Basic RIP Parameters Default RIP ConfigurationRouter rip Network network number 38-22 Configuring Summary Addresses and Split Horizon Configuring RIP AuthenticationIp rip authentication key-chain name-of-chain Ip rip authentication mode text md5 Switchconfig-router#neighbor 2.2.2.2 peer-group mygroup Configuring Split HorizonIp summary-address rip ip address ip-network mask No ip split horizon No ip split-horizon Configuring Ospf38-25 38-26 Default Ospf Configuration 38-27 Ospf Nonstop Forwarding 38-28 Ospf NSF Awareness Configuring Ospf Interfaces Configuring Basic Ospf Parameters38-29 38-30 38-31 Configuring Ospf Area Parameters 38-32 Configuring Other Ospf Parameters 38-33 Changing LSA Group Pacing Configuring a Loopback InterfaceIp address address mask 38-34 Monitoring Ospf Configuring Eigrp38-35 38-36 38-37 Default Eigrp Configuration 38-38 Eigrp Nonstop Forwarding Router eigrp autonomous-system Configuring Basic Eigrp ParametersNetwork network-number Eigrp log-neighbor-changes No auto-summary Configuring Eigrp InterfacesIp summary-address eigrp 38-40 Ip hello-interval eigrp autonomous-system-number Configuring Eigrp Route AuthenticationNo ip split-horizon eigrp autonomous-system-number Show ip eigrp interface 38-42 Eigrp Stub Routing Monitoring and Maintaining Eigrp Configuring BGP38-43 EBGP, IBGP, and Multiple Autonomous Systems 38-44 38-45 Default BGP Configuration 38-46 38-47 Nonstop Forwarding Awareness Router bgp autonomous-system Enabling BGP RoutingNetwork network-number mask network-mask Route-map route-map-name 38-49 Switch# show ip bgp neighbors Switchconfig-router#neighbor 192.208.10.2 remote-asManaging Routing Policy Changes 38-50 Show ip bgp neighbors Type of Reset Advantages DisadvantagesClear ip bgp * address Show ip bgp 38-52 Configuring BGP Decision Attributes 38-53 Configuring BGP Filtering by Neighbor Configuring BGP Filtering with Route Maps38-54 Out weight weight Ip as-path access-list access-list-numberRoute-map map-tag in out Show ip bgp neighbors paths 38-56 Configuring Prefix Lists for BGP Filtering Ip community-listcommunity-list-number Configuring BGP Community FilteringPermit deny community-number Send-community Set comm-list list-num delete Configuring BGP Neighbors and Peer GroupsIp bgp-community new-format Show ip bgp community 38-59 38-60 Configuring Aggregate Addresses Configuring BGP Route Reflectors Configuring Routing Domain Confederations38-61 Route-reflector-client Configuring Route DampeningBgp cluster-id cluster-id No bgp client-to-client reflection 38-63 Monitoring and Maintaining BGP 38-64 Configuring Multi-VRF CE 38-65 Understanding Multi-VRF CE 38-66 Multi-VRF CE Configuration Guidelines Default Multi-VRF CE ConfigurationVRF 38-67 Route-target export import both Configuring VRFsImport map route-map Ip vrf forwarding vrf-name Show ip vrf brief detail interfaces Configuring a VPN Routing SessionLog-adjacency-changes Redistribute bgp Multi-VRF CE Configuration Example Configuring BGP PE to CE Routing Sessions38-70 VPN2 CE1 38-71 38-72 Configuring Switch a Switchconfig-router-af#network 8.8.1.0 mask Switchconfig-router-af#network 8.8.2.0 maskSwitchconfig-if#ip address 208.0.0.20 38-73 38-74 Router# configure terminal Displaying Multi-VRF CE Status Configuring Unicast Reverse Path Forwarding38-75 Configuring Distributed Cisco Express Forwarding Configuring Protocol-Independent Features38-76 38-77 Configuring the Number of Equal-Cost Routing Paths Router bgp rip ospf eigrp Configuring Static Unicast RoutesMaximum-paths maximum Show ip route Route Source Default Distance Specifying Default Routes and NetworksIp default-network network number Specify a default network 38-79 38-80 Using Route Maps to Redistribute Routing Information 38-81 38-82 38-83 Configuring Policy-Based Routing 38-84 PBR Configuration Guidelines 38-85 Enabling PBR Ip route-cache policy Ip policy route-map map-tagIp local policy route-map map-tag 38-86 Filtering Routing Information Setting Passive Interfaces38-87 Filtering Sources of Routing Information Controlling Advertising and Processing in Routing UpdatesRouter bgp rip eigrp 38-88 Distance weight ip-address ip-address mask Managing Authentication KeysIp access list 38-89 38-90 Monitoring and Maintaining the IP Network 38-91 38-92 Understanding IPv6 Configuring IPv6 Unicast Routing39-1 39-2 IPv6 Addresses Bit Wide Unicast Addresses Supported IPv6 Unicast Routing Features39-3 Path MTU Discovery for IPv6 Unicast DNS for IPv6ICMPv6 Neighbor Discovery 39-5 IPv6 Applications Dual IPv4 and IPv6 Protocol Stacks Unsupported IPv6 Unicast Routing Features39-6 Limitations IPv6 and Switch Stacks39-7 39-8 Dual IPv4-and IPv6 SDM Templates SDM Templates39-9 39-10 Configuring IPv6 Configuring IPv6 Addressing and Enabling IPv6 Routing Default IPv6 Configuration39-11 39-12 Ip routing Enable routing on the switch Configuring IPv4 and IPv6 Protocol StacksSwitchconfig-if#ipv6 address 20010DB8c181/64 eui 39-13 39-14 Configuring CEF and dCEF for IPv6 Configuring IPv6 Icmp Rate LimitingIpv6 icmp error-interval interval bucketsize Show ipv6 interface interface-id 39-16 Configuring Static Routing for IPv6 Ipv6 route ipv6-prefix/prefix length Administrative distanceIpv6-address interface-id ipv6-address 39-17 Show ipv6 route static updated Configuring RIP for IPv6Show ipv6 static ipv6-address Interface-id recursive detail 39-19 39-20 Configuring Ospf for IPv6 39-21 Displaying IPv6 Switch# show ipv6 interface39-22 Switch# show ipv6 protocols Switch# show ipv6 cef /0Switch# show ipv6 rip 39-23 Switch# show ipv6 static Switch# show ipv6 neighborsSwitch# show ipv6 route Switch# show ipv6 traffic 39-25 39-26 Understanding Hsrp Configuring Hsrp and Enhanced Object Tracking40-1 40-2 40-3 Multiple Hsrp Hsrp and Switch Stacks Configuring Hsrp40-4 Hsrp Configuration Guidelines Default Hsrp ConfigurationEnabling Hsrp 40-5 Standby group-number ip ip-address Switch# show standbySecondary Show standby interface-id group 40-7 Configuring Hsrp Priority Standby group-number priority Priority preempt delay delayStandby group-number track 40-8 Configuring Hsrp Authentication and Timers Configuring MhsrpSwitchconfig-if#standby 2 ip 40-9 Standby group-number timers hellotime Standby group-number authentication stringSwitchconfig-if#standby 1 authentication word Holdtime Configuring Hsrp Groups and Clustering Displaying Hsrp ConfigurationsEnabling Hsrp Support for Icmp Redirect Messages Show standby interface-idgroup brief detail Understanding Enhanced Object Tracking Configuring Enhanced Object Tracking40-12 Tracking Interface Line-Protocol or IP Routing State Configuring Enhanced Object Tracking FeaturesTrack object-number interface 40-13 Switch# show track 33 Track Configuring a Tracked ListTrack track-numberlist boolean Object object-number not Threshold weight up number WeightTrack track-numberlist threshold 40-15 Percentage Track track-number list thresholdObject object-number Threshold percentage up number 40-17 Configuring Hsrp Object Tracking Show standby Configuring Other Tracking Characteristics40-18 Understanding Wccp Configuring Web Cache Services By Using41-1 41-2 Wccp Message Exchange Wccp Negotiation Packet Redirection and Service GroupsMD5 Security 41-3 41-4 Wccp and Switch Stacks Unsupported Wccp Features Configuring WccpDefault Wccp Configuration Wccp Configuration Guidelines 41-6 Enabling the Web Cache Service 41-7 41-8 Switchconfig-if-range#switchport access vlan Switchconfig# interface range gigabitethernet1/0/3Monitoring and Maintaining Wccp 41-9 41-10 Enabled / disabled 42-1 Configuring IP Multicast Routing IP Multicast Routing Protocols 42-2 Igmp Version Understanding Igmp42-3 PIM Versions Understanding PIMPIM Modes 42-4 42-5 PIM Stub Routing 42-6 Auto-RP Multicast Forwarding and Reverse Path Check Bootstrap Router42-7 Network Port Understanding Dvmrp42-8 Understanding Cgmp Multicast Routing and Switch Stacks42-9 Default Multicast Routing Configuration Configuring IP Multicast RoutingMulticast Routing Configuration Guidelines 42-10 PIMv1 and PIMv2 Interoperability Auto-RP and BSR Configuration Guidelines42-11 Ip multicast-routing distributed Configuring Basic Multicast Routing42-12 Ip pim version 1 Configuring PIM Stub RoutingIp pim dense-mode sparse-mode Sparse-dense-mode Manually Assigning an RP to Multicast Groups Configuring a Rendezvous PointIp pim passive 42-14 Ip pim rp-address ip-address Access-list-number override42-15 42-16 Configuring Auto-RP Ip pim send-rp-announce interface-id Scope ttl group-list access-list-numberInterval seconds 42-17 Show ip pim rp mapping Ip pim send-rp-discovery scope ttlShow ip pim rp 42-18 Ip pim rp-announce-filter rp-list Access-list-number group-list42-19 Ip pim bsr-border Configuring PIMv2 BSR42-20 42-21 Ip multicast boundary Hash-mask-length priority Ip pim bsr-candidate interface-id42-22 Ip pim rp-candidate interface-id Group-list access-list-number42-23 Show ip pim rp group-name Using Auto-RP and a BSRGroup-address mapping Show ip pim rp-hash group Troubleshooting PIMv1 and PIMv2 Interoperability Problems Configuring Advanced PIM FeaturesMonitoring the RP Mapping Information Understanding PIM Shared Tree and Source Tree Shared Tree and Source Tree Shortest-Path Tree 42-26 Ip pim spt-threshold kbps infinity Delaying the Use of PIM Shortest-Path Tree42-27 Modifying the PIM Router-Query Message Interval Configuring Optional Igmp FeaturesIp pim query-interval seconds Show ip igmp interface interface-id Configuring the Switch as a Member of a Group Default Igmp ConfigurationIp igmp join-group group-address 42-29 Ip igmp access-group access-list-number Controlling Access to IP Multicast GroupsShow ip igmp interface interface-id Verify your entries 42-30 Modifying the Igmp Host-Query Message Interval Changing the Igmp VersionIp igmp version 1 Query-interval or the ip igmp query-max-response-time Ip igmp querier-timeout seconds Changing the Igmp Query Timeout for IGMPv2Ip igmp query-interval seconds 42-32 Changing the Maximum Query Response Time for IGMPv2 Configuring the Switch as a Statically Connected MemberIp igmp query-max-response-time 42-33 Enabling Cgmp Server Support Configuring Optional Multicast Routing FeaturesIp igmp static-group group-address 42-34 Ip cgmp proxy Configuring sdr Listener Support42-35 Enabling sdr Listener Support Ip sdr listen Enable sdr listener supportLimiting How Long an sdr Cache Entry Exists 42-36 42-37 Configuring an IP Multicast Boundary 42-38 Configuring Basic Dvmrp Interoperability Features 42-39 Configuring Dvmrp Interoperability 42-40 Ip dvmrp metric metric list 42-41 Configuring a Dvmrp Tunnel Neighbor-list access-list-number Access-list-number distanceAdvertising Network 0.0.0.0 to Dvmrp Neighbors Ip dvmrp accept-filter Ip dvmrp default-information Configuring Advanced Dvmrp Interoperability FeaturesResponding to mrinfo Requests Originate only 42-44 Enabling Dvmrp Unicast Routing 42-45 Rejecting a Dvmrp Nonpruning Neighbor 42-46 Enter interface configuration mode Controlling Route Exchanges By default, 7000 routes are advertised. The range is 0 toLimiting the Number of Dvmrp Routes Advertised Changing the Dvmrp Route Threshold Default is 10,000 routes. The range is 1 to Configuring a Dvmrp Summary AddressRoute-count 42-48 42-49 Ip dvmrp summary-address address Disabling Dvmrp AutosummarizationMask metric value No ip dvmrp auto-summary Ip dvmrp metric-offset in out Adding a Metric Offset to the Dvmrp RouteIncrement 42-51 Clearing Caches, Tables, and Databases Monitoring and Maintaining IP Multicast RoutingDisplaying System and Network Statistics 42-52 42-53 Monitoring IP Multicast Routing 42-54 Understanding Msdp Configuring Msdp43-1 43-2 Msdp Operation 43-3 Msdp Benefits Default Msdp Configuration Configuring MsdpConfiguring a Default Msdp Peer 43-4 Prefix-list list Ip msdp default-peer ip-address name43-5 Ip prefix-list name description string Caching Source-Active StateSeq number permit deny network Ip msdp description peer-name 43-7 Ip msdp cache-sa-state list Requesting Source Information from an Msdp Peer Switchconfig# ip msdp sa-requestIp msdp sa-request ip-address name 43-8 Redistributing Sources Controlling Source Information that Your Switch OriginatesIp msdp redistribute list 43-9 43-10 Filtering Source-Active Request Messages Name list access-list-numberIp msdp filter-sa-request ip-address 43-11 Using a Filter Controlling Source Information that Your Switch ForwardsIp msdp sa-filter out ip-address name Route-map map-tag 43-13 Using TTL to Limit the Multicast Data Sent in SA Messages Controlling Source Information that Your Switch ReceivesIp msdp ttl-threshold ip-address name Ttl Ip msdp sa-filter in ip-address name Switchconfig# ip msdp sa-filter in switch.cisco.com43-15 Shutting Down an Msdp Peer Configuring an Msdp Mesh GroupIp msdp mesh-group name ip-address 43-16 Ip msdp shutdown peer-name peer Including a Bordering PIM Dense-Mode Region in MsdpIp msdp border sa-address interface-id 43-17 43-18 Configuring an Originating Address other than the RP Address Clear ip msdp peer peer-addressname Monitoring and Maintaining MsdpClear ip msdp statistics peer-addressname Clear ip msdp sa-cache group-addressname 43-20 Understanding Fallback Bridging Configuring Fallback BridgingFallback Bridging Overview 44-1 44-2 Fallback Bridging and Switch Stacks Configuring Fallback Bridging44-3 Fallback Bridging Configuration Guidelines Default Fallback Bridging ConfigurationCreating a Bridge Group 44-4 Vlan-bridge Bridge bridge-group protocolBridge-group bridge-group 44-5 Switchconfig# bridge 10 protocol vlan-bridge Adjusting Spanning-Tree Parameters44-6 Changing the Interface Priority Changing the VLAN-Bridge Spanning-Tree PriorityBridge bridge-group priority number Bridge-group bridge-grouppriority Bridge-group bridge-group path-cost Assigning a Path CostCost 44-8 Switchconfig# bridge 10 hello-time Adjusting Bpdu IntervalsBridge bridge-group hello-time seconds 44-9 Switchconfig# bridge 10 max-age Switchconfig# bridge 10 forward-timeBridge bridge-group forward-time Bridge bridge-group max-age seconds Disabling the Spanning Tree on an Interface Monitoring and Maintaining Fallback BridgingClear bridge bridge-group Show bridge bridge-group group 44-12 45-1 Troubleshooting 45-2 Recovering from a Software Failure Switch flashinit Recovering from a Lost or Forgotten PasswordSwitch loadhelper Switch copy xmodem flashimagefilename.bin 45-4 45-5 Procedure with Password Recovery Enabled 45-6 Copy the configuration file into memory Switch dir flash Procedure with Password Recovery Disabled45-7 45-8 Preventing Switch Stack Problems 45-9 Recovering from a Command Switch Failure Switchconfig# no cluster commander-address Replacing a Failed Command Switch with a Cluster Member45-10 45-11 Replacing a Failed Command Switch with Another Switch 45-12 Troubleshooting Power over Ethernet Switch Ports Recovering from Lost Cluster Member ConnectivityPreventing Autonegotiation Mismatches 45-13 Disabled Port Caused by False Link Up Disabled Port Caused by Power LossShow controllers power inline privileged Exec command SFP Module Security and Identification Using Ping Monitoring TemperatureMonitoring SFP Module Status Understanding Ping Executing Ping Switch# pingCharacter Description 45-16 Understanding Layer 2 Traceroute Using Layer 2 TracerouteUsage Guidelines 45-17 Displaying the Physical Path Using IP TracerouteUnderstanding IP Traceroute 45-18 Executing IP Traceroute Switch# traceroute ipTraceroute ip host Trace the path that packets take through the network Understanding TDR Using TDR45-20 Enabling Debugging on a Specific Feature Using Debug CommandsRunning TDR and Displaying the Results 45-21 Redirecting Debug and Error Message Output Enabling All-System Diagnostics45-22 45-23 Using the show platform forward CommandUdp 10 45-24 Basic crashinfo Files Using the crashinfo Files45-25 Extended crashinfo Files Using On-Board Failure LoggingUnderstanding Obfl 45-26 45-27 Configuring Obfl Show logging onboard module Displaying Obfl Information45-28 Understanding Online Diagnostics Configuring Online Diagnostics46-1 Scheduling Online Diagnostics Configuring Online DiagnosticsDiagnostic schedule switch Non-disruptive daily hhmm Diagnostic monitor interval switch Configuring Health-Monitoring DiagnosticsDiagnostic content command output Diagnostic monitor syslog Diagnostic monitor switch number test Diagnostic monitor threshold switchShow diagnostic content post result Schedule status switch Starting Online Diagnostic Tests Running Online Diagnostic TestsDiagnostic start switch number All basic non-disruptive 46-6 Displaying Online Diagnostic Tests and Test Results MIB List Supported MIBsCISCO-FTP-CLIENT-MIB CISCO-HSRP-MIB CISCO-RTTMON-MIB CISCO-SMI-MIB CISCO-IGMP-FILTER-MIBETHERLIKE-MIB IEEE8021-PAE-MIB IEEE8023-LAG-MIB IGMP-MIB INET-ADDRESS-MIB IPMROUTE-MIB TCP-MIB UDP-MIB Using FTP to Access the MIB Files Working with the Flash File System Displaying Available File Systems Switch# show file systems Field Value Setting the Default File System Displaying Information about Files on a File System Cd newconfigsChanging Directories and Displaying the Working Directory Pwd Creating and Removing Directories Mkdir oldconfigsCopying Files Deleting Files Switch# delete myconfigCreating, Displaying, and Extracting Files Flash Archive /create destination-urlArchive /table source-url Extract a file into a directory on the flash file system Archive /xtract source-urlDirectories are extracted More /ascii /binary /ebcdic Working with Configuration Files Configuration File Types and Location Guidelines for Creating and Using Configuration Files Copying Configuration Files By Using Tftp Creating a Configuration File By Using a Text Editor Uploading the Configuration File By Using Tftp Downloading the Configuration File By Using Tftp Copying Configuration Files By Using FTP Ip ftp password password Downloading a Configuration File By Using FTPIp ftp username username Ftp // username password @ location /directory Uploading a Configuration File By Using FTPFilename systemrunning-config Filename nvramstartup-config Copy systemrunning-config Copying Configuration Files By Using RCPCopy nvramstartup-config Ftp // username password @ location /directory Filename Hostname Switch1 Ip rcmd remote-username User0 Systemrunning-config Downloading a Configuration File By Using RCPNvramstartup-config Ip rcmd remote-username username Uploading a Configuration File By Using RCP Clearing Configuration InformationSwitch# copy nvramstartup-config rcp Deleting a Stored Configuration File Clearing the Startup Configuration FileWorking with Software Images File Format of Images on a Server or Cisco.com Image Location on the Switch Field Description Copying Image Files By Using Tftp Downloading an Image File By Using Tftp Preparing to Download or Upload an Image File By Using Tftp Archive download-sw Allow-feature-upgrade /directoryOverwrite /reload Archive download-sw /directory Archive upload-sw Uploading an Image File By Using TftpTftp //location /directory /image-name .tar Preparing to Download or Upload an Image File By Using FTP Copying Image Files By Using FTP Downloading an Image File By Using FTP Directory /overwrite /reload Archive download-sw /allow-feature-upgradeFor /directory /image-name1 .tar Directory /image-name2 .tar image-name3 .tar Uploading an Image File By Using FTP Copying Image Files By Using RCP Preparing to Download or Upload an Image File By Using RCP File By Using RCP section on page B-31 Downloading an Image File By Using RCP Or Upload an Image File By Using RCP section on Uploading an Image File By Using RCP Rcp // username @ location /directory /image-na Copying an Image File from One Stack Member to AnotherMe.tar Destination-stack-member-number /force-reload Archive copy-sw /destination-systemSource-stack-member-number For /destination-system destination-stack-member-number Access Control Lists Unsupported Commands Cisco IOS Release 12.237SEUnsupported Privileged Exec Commands Unsupported Global Configuration Commands ARP Commands Archive CommandsBoot Loader Commands Debug Commands Bridge bridge-groupacquire Fallback BridgingBridge crb Bridge bridge-group domain domain-name bridge irb X25 map bridge x.121-address broadcast options-keywords Hsrp Interface Commands Igmp Snooping CommandsIP Multicast Routing Show ip pim vc group-address name type number Ip pim accept-rpaddress auto-rpgroup-access-list-numberShow ip rtp header-compression type number detail Ip multicast-routing vrf vrf-name IP Unicast Routing Unsupported Privileged Exec or User Exec Commands Unsupported VPN Configuration Commands Unsupported BGP Router Configuration CommandsUnsupported Route Map Commands Show cable-diagnostics prbs Test cable-diagnostics prbs MAC Address CommandsMiscellaneous Set tag tag-value Msdp NetFlow Commands Unsupported Global Configuration Command Network Address Translation NAT CommandsUnsupported Policy-Map Configuration Command QoS Unsupported User Exec Commands Unsupported Interface Configuration CommandUnsupported Privileged Exec Command Spanning Tree IN-1 Numerics IN-2 ACLs Eigrp CDP Lldp RIPHsrp TACACS+ Cidr BGPIN-4 IN-5 Bpdu CEF CDPCgmp CLI IN-7 CNS IN-8 DNS DhcpIN-9 TACACS+ Udld SnmpVmps Wccp IN-11 Dhcp option IN-12 DTP IN-13 Dvmrp IN-14 Dynamic ARP inspection IN-15 Lacp FIB STPIN-16 FTP Mstp STPIN-17 Icmp HttpsIN-18 IN-19 Igmp IN-20 IN-21 IP addresses IN-22 Mbone IN-23 IGP IN-24 IP unicast routing IN-25 ISL IN-26 LLDP-MED IN-27 Mhsrp MDAIN-28 IN-29 Msdp IST CSTMTU IN-30 IN-31 NAC IN-32 NSSA, Ospf PBR ObflIN-33 IN-34 PIM IN-35 Port-based authentication Vvid PvidIN-36 IN-37 Private VLANs IN-38 QoS IN-39 IN-40 RCP RFC Radius TACACS+Rmon IN-41 Rspan RPSRstp IN-42 IN-43 SDM IN-44 Snmp SRR SpanIN-45 VTP SSLIN-46 IN-47 Stacks, switch IN-48 LLDP-MED Ospf IN-49 STP IN-50 IN-51 System message logging IN-52 IN-53 IN-54 IN-55 VLANs VQP VPNIN-56 IN-57 WTD IN-58

Cisco Systems 3750E Spanning Tree and Redundant Connectivity, Spanning-Tree Address Management

Models: 3750E

Spanning Tree and Redundant Connectivity

Figure 18-4 Spanning Tree and Redundant Connectivity

Spanning-Tree Address Management

Accelerated Aging to Retain Connectivity

18-9