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Cisco nexus 5000 series Configuration Manual

Cisco nexus 5000 series Configuration Manual

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Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration
Guide, Release 5.1(3)N1(1)
First Published: December 05, 2011
Last Modified: November 27, 2012
Americas Headquarters
Cisco Systems, Inc.
170 West Tasman Drive
San Jose, CA 95134-1706
USA
http://www.cisco.com
Tel: 408 526-4000
800 553-NETS (6387)
Fax: 408 527-0883
Text Part Number: OL-25842-01

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Summary of Contents for Cisco nexus 5000 series

  • Page 1 Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) First Published: December 05, 2011 Last Modified: November 27, 2012 Americas Headquarters Cisco Systems, Inc. 170 West Tasman Drive San Jose, CA 95134-1706 http://www.cisco.com Tel: 408 526-4000 800 553-NETS (6387)
  • Page 2 Cisco and the Cisco logo are trademarks or registered trademarks of Cisco and/or its affiliates in the U.S. and other countries. To view a list of Cisco trademarks, go to this URL: www.cisco.com/go/trademarks . Third-party trademarks mentioned are the property of their respective owners. The use of the word partner does not imply a partnership relationship between Cisco and any other company.
  • Page 3: Table Of Contents

    Information About Ethernet Interfaces Interface Command Information About Unified Ports Guidelines and Limitations for Unified Ports Unidirectional Link Detection Parameter Default UDLD Configuration UDLD Aggressive and Nonaggressive Modes Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 4 Configuring the Debounce Timer Configuring the Description Parameter Disabling and Restarting Ethernet Interfaces Displaying Interface Information Default Physical Ethernet Settings Configuring VLANs C H A P T E R 4 Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 5 Configuring an Interface as a Private VLAN Promiscuous Port Configuring a Promiscuous Trunk Port Configuring an Isolated Trunk Port Configuring Private VLANs on FEX Trunk Ports Configuring the Allowed VLANs for PVLAN Trunking Ports Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 6 LACP ID Parameters Channel Modes LACP Marker Responders LACP-Enabled and Static Port Channel Differences Configuring Port Channels Creating a Port Channel Adding a Port to a Port Channel Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 7 Per-VLAN Consistency Check vPC Auto-Recovery vPC Peer Links vPC Peer Link Overview vPC Number vPC Interactions with Other Features Configuring vPC Peer Links and Links to the Core Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 8 Viewing the Graceful Type-1 Check Status Viewing a Global Type-1 Inconsistency Viewing an Interface-Specific Type-1 Inconsistency Viewing a Per-VLAN Consistency Status vPC Example Configurations Dual Homed Fabric Extender vPC Configuration Example Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) viii OL-25842-01...
  • Page 9 STP MAC Address Allocation Understanding BPDUs Election of the Root Bridge Creating the Spanning Tree Topology Understanding Rapid PVST+ Rapid PVST+ Overview Rapid PVST+ BPDUs Proposal and Agreement Handshake Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 10 Specifying the Link Type Restarting the Protocol Verifying the Rapid PVST+ Configuration Configuring Multiple Spanning Tree C H A P T E R 1 1 Information About MST Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 11 Configuring the Switch Priority Configuring the Hello Time Configuring the Forwarding-Delay Time Configuring the Maximum-Aging Time Configuring the Maximum-Hop Count Configuring PVST Simulation Globally Configuring PVST Simulation Per Port Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 12 C H A P T E R 1 3 Information About Flex Links Guidelines and Limitations for Flex Link Default Settings for Flex Link Configuring Flex Links Configuring Flex Link Preemption Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 13 MVR Interoperation with Other Features Licensing Requirements for MVR Guidelines and Limitations for MVR Default MVR Settings Configuring MVR Configuring MVR Global Parameters Configuring MVR Interfaces Verifying the MVR Configuration Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01 xiii...
  • Page 14 Forwarding Model Connection Model Static Pinning Fabric Interface Connection Port Channel Fabric Interface Connection Port Numbering Convention Fabric Extender Image Management Fabric Extender Hardware Chassis Ethernet Interfaces Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 15 Configuring the Cisco Nexus N2248TP-E Fabric Extender Configuring the Shared Buffer Configuring the Queue-Limit at the Global Level Configuring the Queue-Limit at the Port Level Configuring Uplink Distance Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 16 Contents Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 17: Preface

    Documentation Feedback, page xix • Obtaining Documentation and Submitting a Service Request, page xix Audience This publication is for network administrators who configure and maintain Cisco Nexus devices and Cisco Nexus 2000 Series Fabric Extenders. Document Conventions Note As part of our constant endeavor to remodel our documents to meet our customers' requirements, we have modified the manner in which we document configuration tasks.
  • Page 18 Means reader take note. Notes contain helpful suggestions or references to material not covered in the Note manual. Means reader be careful. In this situation, you might do something that could result in equipment damage Caution or loss of data. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) xviii OL-25842-01...
  • Page 19: Documentation Feedback

    What's New in Cisco Product Documentation, at: http:// www.cisco.com/c/en/us/td/docs/general/whatsnew/whatsnew.html. To receive new and revised Cisco technical content directly to your desktop, you can subscribe to the What's New in Cisco Product Documentation RSS feed. RSS feeds are a free service.
  • Page 20 Preface Obtaining Documentation and Submitting a Service Request Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 21: New And Changed Information

    Table 1: New Features Feature Description Where Documented PVLAN Trunk Over FEX Enables PVLAN trunk over FEX ports Configuring Private Ports VLANs, on page 51 Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 22: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    New and Changed Information New and Changed Information for this Release Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 23: Overview

    VLAN must be forwarded through a bridge or a router. All ports are assigned to the default VLAN (VLAN1) when the device comes up. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 24: Private Vlans

    STP protocol. Note Cisco NX-OS uses the extended system ID and MAC address reduction; you cannot disable these features. In addition, Cisco has created some proprietary features to enhance the spanning tree activities. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1)
  • Page 25: Rapid Pvst

    • Root Guard— Root guard prevents a port from becoming a root port or a blocked port. If you configure a port with root guard then the port receives a superior BPDU and it immediately goes to root-inconsistent (blocked) state. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 26: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    Overview STP Extensions Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 27: Configuring Ethernet Interfaces

    ◦ Slot 4 includes the ports on the lower expansion module (if populated). • Port number— Port number within the group. The interface numbering convention is extended to support use with a Cisco Nexus Fabric Extender as follows: Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1)
  • Page 28: Information About Unified Ports

    Fabric Extender discovered through the interface. The chassis ID ranges from 100 to 199. Information About Unified Ports Cisco Nexus unified ports allow you to configure a physical port on a Cisco Nexus device switch as a 1/10-Gigabit Ethernet, Fibre Channel over Ethernet (FCoE), or 2-, 4-, 8-Gigabit native Fibre Channel port.
  • Page 29: Default Udld Configuration

    This check cannot be performed by autonegotiation, because autonegotiation operates at Layer 1. A Cisco Nexus device periodically transmits UDLD frames to neighbor devices on LAN ports with UDLD enabled. If the frames are echoed back within a specific time frame and they lack a specific acknowledgment (echo), the link is flagged as unidirectional and the LAN port is shut down.
  • Page 30: Udld Aggressive And Nonaggressive Modes

    Interface Speed Cisco Discovery Protocol The Cisco Discovery Protocol (CDP) is a device discovery protocol that runs over Layer 2 (the data link layer) on all Cisco-manufactured devices (routers, bridges, access servers, and switches) and allows network management applications to discover Cisco devices that are neighbors of already known devices. With CDP, network management applications can learn the device type and the Simple Network Management Protocol (SNMP) agent address of neighboring devices that are running lower-layer, transparent protocols.
  • Page 31: Error-Disabled State

    About Port Profiles You can create a port profile that contains many interface commands and apply that port profile to a range of interfaces on the Cisco Nexus device. Port profiles can be applied to the following interface types: • Ethernet •...
  • Page 32: Guidelines And Limitations For Port Profiles

    • There are no default configurations associated with a port profile. • A subset of commands are available under the port profile configuration mode, depending on which interface type that you specify. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 33: Debounce Timer Parameters

    MTU Configuration The Cisco Nexus device switch does not fragment frames. As a result, the switch cannot have two ports in the same Layer 2 domain with different maximum transmission units (MTUs). A per-physical Ethernet interface MTU is not supported. Instead, the MTU is set according to the QoS classes. You modify the MTU by setting class and policy maps.
  • Page 34: Configuring Unified Ports

    Configuring Unified Ports Before You Begin Confirm that you have a supported Cisco Nexus switch. Unified Ports are available on the following Cisco Nexus switches: If you're configuring a unified port as Fibre Channel or FCoE, confirm that you have enabled the feature fcoe command.
  • Page 35: Configuring The Udld Mode

    To use the aggressive UDLD mode, you must configure both ports for the aggressive mode. Before you begin, UDLD must be enabled for the other linked port and its device. Note Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 36: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    1/4 switch(config-if)# udld aggressive This example shows how to disable UDLD for an Ethernet port: switch# configure terminal switch(config)# interface ethernet 1/4 Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 37: Configuring Interface Speed

    You can disable link negotiation using the no negotiate auto command. By default, auto-negotiation is enabled on 1-Gigabit ports and disabled on 10-Gigabit ports. This command is equivalent to the Cisco IOS speed non-negotiate command. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 38: Configuring The Cdp Characteristics

    Configuring the CDP Characteristics You can configure the frequency of Cisco Discovery Protocol (CDP) updates, the amount of time to hold the information before discarding it, and whether or not to send Version-2 advertisements. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1)
  • Page 39: Enabling Or Disabling Cdp

    Enabling or Disabling CDP You can enable or disable CDP for Ethernet interfaces. This protocol works only when you have it enabled on both interfaces on the same link. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 40: Enabling The Error-Disabled Detection

    Base ports in Cisco Nexus 5500 never get error disabled due to pause rate-limit like in the Cisco Nexus Note 5020 or 5010 switch.
  • Page 41: Enabling The Error-Disabled Recovery

    You can specify the application to bring the interface out of the error-disabled (err-disabled) state and retry coming up. It retries after 300 seconds, unless you configure the recovery timer (see the errdisable recovery interval command). Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 42: Configuring The Error-Disabled Recovery Interval

    The default is 300 seconds. SUMMARY STEPS 1. switch# configure terminal 2. switch(config)# errdisable recovery interval interval 3. switch(config)# show interface status err-disabled 4. (Optional) switch(config)# copy running-config startup-config Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 43: Port Profiles

    4. (Optional) show port-profile 5. (Optional) copy running-config startup-config DETAILED STEPS Command or Action Purpose Step 1 configure terminal Enters configuration mode. Example: switch# configure terminal switch(config)# Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 44: Modifying A Port Profile

    You can remove commands from a port profile using the no form of the command. When you remove a command from the port profile, the corresponding command is removed from the interface that is attached to the port profile. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 45: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    This example shows how to remove commands from the port profile named ppEth configured for an Ethernet interface: switch# configure terminal switch(config)# port-profile ppEth switch(config-port-prof)# switchport mode trunk switch(config-port-prof)# switchport trunk allowed vlan 300-400 switch(config-port-prof)# flowcontrol receive on switch(config-port-prof)# no speed 10000 switch(config-port-prof)# Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 46: Enabling A Specific Port Profile

    Displays the port profile configuration. Example: switch(config)# show port-profile name Step 6 (Optional) copy running-config startup-config Copies the running configuration to the startup configuration. Example: switch(config)# copy running-config startup-config Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 47: Inheriting A Port Profile

    Step 4 exit Exits the port profile configuration mode. Example: switch(config-port-prof)# exit switch(config)# Step 5 show port-profile (Optional) Displays the port profile configuration. Example: switch(config)# show port-profile name Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 48: Removing An Inherited Port Profile

    This example shows how to remove an inherited port profile named ppEth from an existing port profile named test: switch# configure terminal switch(config)# port-profile test switch(config-port-prof)# no inherit port-profile ppEth switch(config-port-prof)# Removing an Inherited Port Profile You can remove an inherited port profile. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 49: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    This example shows how to remove the inherited port profile named adam from the port profile named test: switch# configure terminal switch(config)# port-profile test Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 50: Assigning A Port Profile To A Range Of Interfaces

    Removing a Port Profile from a Range of Interfaces You can remove a port profile from some or all of the interfaces to which you have applied the profile. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 51: Configuration Examples For Port Profiles

    Ethernet1/14 !Command: show running-config interface Ethernet1/14 !Time: Thu Aug 26 07:01:32 2010 version 5.0(2)N1(1) interface Ethernet1/14 switch(config)# port-profile type ethernet alpha Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 52: Configuring The Debounce Timer

    To enable or disable the debounce timer, perform this task: SUMMARY STEPS 1. switch# configure terminal 2. switch(config)# interface type slot/port 3. switch(config-if)# link debounce time milliseconds Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 53: Configuring The Description Parameter

    Enters global configuration mode. Step 2 switch(config)# interface type slot/port Enters interface configuration mode for the specified interface. Step 3 switch(config-if)# description test Specifies the description for the interface. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 54: Disabling And Restarting Ethernet Interfaces

    This example shows how to restart an Ethernet interface: switch# configure terminal switch(config)# interface ethernet 1/4 switch(config-if)# no shutdown Displaying Interface Information To view configuration information about the defined interfaces, perform one of these tasks: Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 55: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    0 underrun 0 if down drop 0 output error 0 collision 0 deferred 0 late collision 0 lost carrier 0 no carrier 0 babble 0 Rx pause 8031547972 Tx pause 0 reset Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 56: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    This example shows how to display the link debounce status (some of the output has been removed for brevity): switch# show interface debounce -------------------------------------------------------------------------------- Port Debounce time Value(ms) -------------------------------------------------------------------------------- Eth1/1 enable Eth1/2 enable Eth1/3 enable This example shows how to display the CDP neighbors: Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 57: Default Physical Ethernet Settings

    Encapsulation ARPA 1500 bytes Port Mode Access Speed Auto (10000) 1 MTU cannot be changed per-physical Ethernet interface. You modify MTU by selecting maps of QoS classes. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 58: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    Configuring Ethernet Interfaces Default Physical Ethernet Settings Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 59: Configuring Vlans

    VLAN. Each VLAN is considered a logical network. If a packet destination address does not belong to the VLAN, it must be forwarded through a router. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 60: Understanding Vlan Ranges

    VLAN, or for in-band management of the switch. Understanding VLAN Ranges The Cisco Nexus device supports VLAN numbers 1 to 4094 in accordance with the IEEE 802.1Q standard. These VLANs are organized into ranges. The switch is physically limited in the number of VLANs it can Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1)
  • Page 61: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    VLANs 3968 to 4049 and 4094 are reserved for internal use; these VLANs cannot be changed or used. Note Cisco NX-OS allocates a group of 82 VLAN numbers for those features, such as multicast and diagnostics, that need to use internal VLANs for their operation. By default, the system allocates VLANs numbered 3968 to 4049 for internal use.
  • Page 62: Creating, Deleting, And Modifying Vlans

    VLAN changes affect only the local switch. A VTP transparent network switch does not advertise its VLAN configuration and does not synchronize its VLAN configuration based on received advertisements. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 63: Guidelines And Limitations For Vtp

    Disabling VLAN 1 from any of these ports prevents VTP from functioning properly. • If you enable VTP, you must configure either version 1 or version 2. On the Cisco Nexus device, 512 VLANs are supported. If these switches are in a distribution network with other switches, the limit remains the same.
  • Page 64: Changing The Range Of Reserved Vlans

    To change the range of reserved VLANs, you must be in global configuration mode. After entering this command, you must do the following tasks: • Enter the copy running-config startup-config command • Reload the device Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 65: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    1006 reserve This will delete all configs on vlans 1006-1087. Continue anyway? (y/n) [no] yes Note: After switch reload, VLANs 1006-1087 will be reserved for internal use. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 66: Configuring A Vlan

    VLAN. You cannot change the name of VLAN1 or the internally allocated VLANs. The default value is VLANxxxx where xxxx represents four numeric digits (including leading zeroes) equal to the VLAN ID number. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 67: Adding Ports To A Vlan

    Sets the access mode of the interface to the specified VLAN. This example shows how to configure an Ethernet interface to join VLAN 5: switch# configure terminal switch(config)# interface ethernet 1/13 switch(config-if)# switchport access vlan 5 Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 68: Configuring Vtp

    Configuring VTP Configuring VTP You can configure VTP in the client or server mode on Cisco Nexus devices. You can enable VTP and then configure the VTP mode (server [default], client, transparent, or off). If you enable VTP, you must configure either version 1 or version 2. If you are using VTP in a Token Ring environment, you must use version 2.
  • Page 69: Verifying The Vlan Configuration

    [brief | id [vlan_id | vlan_range] | name name | Displays selected configuration information for the defined summary ] VLAN(s). switch# show system vlan reserved Displays the system reserved VLAN range. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 70: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    Configuring VLANs Verifying the VLAN Configuration Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 71: Configuring Private Vlans

    VLAN. The secondary VLAN ID differentiates one subdomain from another. The secondary VLANs can either be isolated VLANs or community VLANs. A host on an isolated VLAN can communicate only with Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 72: Primary And Secondary Vlans In Private Vlans

    VLANs or in any isolated VLANs at the Layer 2 level. Private VLAN Ports The three types of PVLAN ports are as follows: Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 73: Primary, Isolated, And Community Private Vlans

    You can configure multiple community VLANs in a PVLAN domain. The ports within one community can Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 74: Associating Primary And Secondary Vlans

    To allow host ports in secondary VLANs to communicate outside the PVLAN, you associate secondary VLANs to the primary VLAN. If the association is not operational, the host ports (community and isolated ports) in the secondary VLAN are brought down. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 75: Private Vlan Promiscuous Trunks

    VLAN tag. Isolated trunk ports are intended to be connected to host servers. To support isolated PVLAN ports on a Cisco Nexus Fabric Extender, the Cisco Nexus device must prevent communication between the isolated ports on the FEX; all forwarding occurs through the switch.
  • Page 76: Broadcast Traffic In Private Vlans

    • You must disable all the FEX isolated trunk ports before configuring FEX trunk ports. • You cannot connect a second switch to a promiscuous or isolated PVLAN trunk. The promiscuous or isolated PVLAN trunk is supported only on host-switch. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 77: Configuring A Private Vlan

    To create a PVLAN, you first create a VLAN, and then configure that VLAN to be a PVLAN. Before You Begin Ensure that the PVLAN feature is enabled. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 78: Associating Secondary Vlans With A Primary Private Vlan

    Each item can be a single secondary VLAN ID or a hyphenated range of secondary VLAN IDs. • The secondary-vlan-list parameter can contain multiple community VLAN IDs and one isolated VLAN Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 79: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    VLANs and a primary VLAN. Step 4 switch(config-vlan)# no private-vlan association (Optional) Removes all associations from the primary VLAN and returns it to normal VLAN mode. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 80: Configuring An Interface As A Private Vlan Host Port

    PVLAN. The secondary VLAN can be either an isolated host-association {primary-vlan-id} {secondary-vlan-id} or community VLAN. Step 5 switch(config-if)# no switchport private-vlan (Optional) Removes the PVLAN association from the port. host-association Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 81: Configuring An Interface As A Private Vlan Promiscuous Port

    VLANs. The secondary VLAN can be either an isolated or community VLAN. secondary-vlan-list} Step 5 switch(config-if)# no switchport private-vlan (Optional) mapping Clears the mapping from the PVLAN. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 82: Configuring A Promiscuous Trunk Port

    Maps the trunk port with the primary and secondary VLANs of mapping trunk {primary-vlan-id} a PVLAN. The secondary VLAN can be either an isolated or {secondary-vlan-id} community VLAN. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 83: Configuring An Isolated Trunk Port

    Configures the port as a secondary trunk port for a PVLAN. trunk [secondary] The secondary keyword is assumed if it is not Note present. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 84: Configuring Private Vlans On Fex Trunk Ports

    Note does not support connections to devices that have promiscuous ports. When promiscuous functionally is required, the device, such as a Cisco Nexus 1000V, must connect to the base ports of the Cisco Nexus device. You must disable all the FEX isolated trunk ports and isolated host ports before configuring PVLANs on Caution the FEX trunk ports.
  • Page 85: Configuring The Allowed Vlans For Pvlan Trunking Ports

    The primary VLANs do not need to be explicitly added to the allowed VLAN list. They are added automatically once there is a mapping between primary and secondary VLANs. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 86: Configuring Native 802.1Q Vlans On Private Vlans

    Typically, you configure 802.1Q trunks with a native VLAN ID, which strips tagging from all packets on that VLAN. This configuration allows untagged traffic and control traffic to transit the Cisco Nexus device. Secondary VLANs cannot be configured with a native VLAN ID on promiscuous trunk ports. Primary VLANs cannot be configured with a native VLAN ID on isolated trunk ports.
  • Page 87: Verifying The Private Vlan Configuration

    This example shows how to display enabled features (some of the output has been removed for brevity): switch# show feature Feature Name Instance State -------------------- -------- -------- fcsp enabled interface-vlan enabled private-vlan enabled udld disabled Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 88: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    Configuring Private VLANs Verifying the Private VLAN Configuration Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 89: Chapter 6 Configuring Access And Trunk Interfaces

    • A trunk port can have two or more VLANs configured on the interface; it can carry traffic for several VLANs simultaneously. Cisco NX-OS supports only IEEE 802.1Q-type VLAN trunk encapsulation. Note Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 90: Understanding Ieee 802.1Q Encapsulation

    To correctly deliver the traffic on a trunk port with several VLANs, the device uses the IEEE 802.1Q encapsulation (tagging) method. This tag carries information about the specific VLAN to which the frame Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 91: Understanding Access Vlans

    If you assign an access VLAN that is also a primary VLAN for a private VLAN, all access ports with that Note access VLAN will also receive all the broadcast traffic for the primary VLAN in the private VLAN mode. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 92: Understanding The Native Vlan Id For Trunk Ports

    • On the ingress side, all untagged data traffic is dropped. • On the egress side, all traffic is tagged. If traffic belongs to native VLAN it is tagged with the native VLAN ID. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 93: Configuring Access And Trunk Interfaces

    VLAN1 only; use this command to change the VLAN for which the access port carries traffic. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 94: Configuring Access Host Ports

    You can configure an Ethernet port as a trunk port; a trunk port transmits untagged packets for the native VLAN plus encapsulated, tagged, packets for multiple VLANs. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 95: Configuring The Native Vlan For 802.1Q Trunking Ports

    2. switch(config)# interface {type slot/port | port-channel number} 3. switch(config-if)# switchport trunk native vlan vlan-id DETAILED STEPS Command or Action Purpose Step 1 switch# configure terminal Enters global configuration mode. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 96: Configuring The Allowed Vlans For Trunking Ports

    You cannot add internally allocated VLANs as allowed VLANs Note on trunk ports. The system returns a message if you attempt to list an internally allocated VLAN as an allowed VLAN. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 97: Configuring Native 802.1Q Vlans

    Typically, you configure 802.1Q trunks with a native VLAN ID, which strips tagging from all packets on that VLAN. This configuration allows all untagged traffic and control traffic to transit the Cisco Nexus device. Packets that enter the switch with 802.1Q tags that match the native VLAN ID value are similarly stripped of tagging.
  • Page 98: Verifying The Interface Configuration

    Displays the interface configuration switch# show interface switchport Displays information for all Ethernet interfaces, including access and trunk interfaces. switch# show interface brief Displays interface configuration information. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 99: Chapter 7 Configuring Port Channels

    LACP Overview, on page 85 Understanding Port Channels Using port channels, Cisco NX-OS provides wider bandwidth, redundancy, and load balancing across the channels. You can collect ports into a static port channel or you can enable the Link Aggregation Control Protocol (LACP).
  • Page 100: Guidelines And Limitations For Port Channel Configuration

    Cisco NX-OS creates a matching port channel automatically if the port channel does not already exist. You can also create the port channel first. In this instance, Cisco NX-OS creates an empty channel group with the same channel number as the port channel and takes the default configuration.
  • Page 101: Compatibility Requirements

    For more information on switch profiles, see the . Compatibility Requirements When you add an interface to a port channel group, Cisco NX-OS checks certain interface attributes to ensure that the interface is compatible with the channel group. Cisco NX-OS also checks a number of operational attributes for an interface before allowing that interface to participate in the port-channel aggregation.
  • Page 102: Load Balancing Using Port Channels

    Load Balancing Using Port Channels Cisco NX-OS load balances traffic across all operational interfaces in a port channel by reducing part of the binary pattern formed from the addresses in the frame to a numerical value that selects one of the links in the channel.
  • Page 103: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    Destination MAC Destination MAC, Destination MAC, port destination IP destination IP, destination port Source TCP/UDP port Source MAC Source MAC, source IP Source MAC, source IP, source port Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 104: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    Cisco Nexus device. The following table shows the criteria used for each configuration: Table 6: Port channel Load-Balancing Criteria for the Cisco Nexus 2232 and Cisco Nexus 2248 Fabric Extenders Configuration Layer 2 Criteria...
  • Page 105: Understanding Lacp

    IP addresses might result in better load balancing. The hardware multicast hw-hash command is not supported on Cisco Nexus 3500 Series switches. It is Note recommended not to configure this command on these switches.
  • Page 106: Lacp Id Parameters

    Configuring Port Channels Understanding LACP When you delete the port channel, Cisco NX-OS automatically deletes the associated channel group. All Note member interfaces revert to their previous configuration. You cannot disable LACP while any LACP configurations are present. LACP ID Parameters LACP uses the following parameters: •...
  • Page 107: Lacp Marker Responders

    Using port channels, data traffic may be dynamically redistributed due to either a link failure or load balancing. LACP uses the Marker Protocol to ensure that frames are not duplicated or reordered because of this redistribution. Cisco NX-OS supports only Marker Responders. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 108: Lacp-Enabled And Static Port Channel Differences

    • Passive Configuring Port Channels Creating a Port Channel You can create a port channel before creating a channel group. Cisco NX-OS automatically creates the associated channel group. If you want LACP-based port channels, you need to enable LACP. Note SUMMARY STEPS 1.
  • Page 109: Adding A Port To A Port Channel

    Adding a Port to a Port Channel You can add a port to a new channel group or to a channel group that already contains ports. Cisco NX-OS creates the port channel associated with this channel group if the port channel does not already exist.
  • Page 110: Configuring Load Balancing Using Port Channels

    Step 3 switch(config)# no port-channel load-balance ethernet (Optional) Restores the default load-balancing algorithm of source-dest-mac. Step 4 switch# show port-channel load-balance (Optional) Displays the port-channel load-balancing algorithm. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 111: Configuring Hardware Hashing For Multicast Traffic

    Enabling LACP LACP is disabled by default; you must enable LACP before you begin LACP configuration. You cannot disable LACP while any LACP configuration is present. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 112: Configuring The Channel Mode For A Port

    SUMMARY STEPS 1. switch# configure terminal 2. switch(config)# interface type slot/port 3. switch(config-if)# channel-group channel-number [force] [mode {on | active | passive}] 4. switch(config-if)# no channel-group number mode Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 113: Configuring The Lacp Fast Timer Rate

    (30 seconds) to the fast rate (1 second). This command is supported only on LACP-enabled interfaces. Before You Begin Ensure that you have enabled the LACP feature. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 114: Configuring The Lacp System Priority And System Id

    Before You Begin Ensure that you have enabled the LACP feature. SUMMARY STEPS 1. switch# configure terminal 2. switch(config)# lacp system-priority priority 3. (Optional) switch# show lacp system-identifier Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 115: Configuring The Lacp Port Priority

    Configures the port priority for use with LACP. Valid values are 1 through 65535, and higher numbers have lower priority. The default value is 32768. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 116: Disabling Lacp Graceful Convergence

    Administratively shuts down the port channel. Example: switch(config-if)# shutdown switch(config-if) # Step 4 no lacp graceful-convergence Disables LACP graceful convergence on the specified port channel. Example: switch(config-if)# no lacp graceful-convergence switch(config-if) # Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 117: Reenabling Lacp Graceful Convergence

    • Ensure that you are in the correct VDC. To switch to the correct VDC, enter the switchto vdc command. SUMMARY STEPS 1. configure terminal 2. interface port-channel number 3. shutdown 4. lacp graceful-convergence 5. no shutdown 6. (Optional) copy running-config startup-config Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 118: Verifying Port Channel Configuration

    # shutdown switch(config-if) # lacp graceful-convergence switch(config-if) # no shutdown switch(config-if) # Verifying Port Channel Configuration Use the following command to verify the port channel configuration information: Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 119: Verifying The Load-Balancing Outgoing Port Id

    To display the load-balancing outgoing port ID, perform one of the tasks: Command Purpose switch# show port-channel load-balance Displays the outgoing port ID. forwarding-path interface port-channel port-channel-id vlan vlan-id dst-ip src-ip dst-mac src-mac l4-src-port port-id l4-dst-port port-id Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 120: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    Missing params will be substituted by 0's. Load-balance Algorithm on switch: source-dest-port crc8_hash:204 Outgoing port id: Ethernet 1/1 Param(s) used to calculate load balance: dst-port: 0 src-port: 0 dst-ip: 1.225.225.225 src-ip: 1.1.10.10 dst-mac: 0000.0000.0000 src-mac: aabb.ccdd.eeff Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 121: Configuring Virtual Port Channels

    A virtual port channel (vPC) allows links that are physically connected to two different Cisco Nexus devices or Cisco Nexus Fabric Extenders to appear as a single port channel by a third device (see the following figure). The third device can be a switch, server, or any other networking device. You can configure vPCs in topologies that include Cisco Nexus devices connected to Cisco Nexus Fabric Extenders.
  • Page 122: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    To create a vPC peer link you configure an EtherChannel on one Cisco Nexus device by using two or more Ethernet ports. On the other switch, you configure another EtherChannel again using two or more Ethernet ports.
  • Page 123: Terminology

    The vPC domain ID must be the same on both switches. • vPC peer-keepalive link—The peer-keepalive link monitors the vitality of a vPC peer Cisco Nexus device. The peer-keepalive link sends configurable, periodic keepalive messages between vPC peer devices.
  • Page 124: Supported Vpc Topologies

    As an example, the following figure refers to a topology built with the Cisco Nexus 2148T fabric extender, where a server has one link only to each fabric extender. A topology with Cisco Nexus 2248TP or with Cisco Nexus 2232PP fabric extender could consist of more links from the server to a single fabric extender.
  • Page 125: Dual Homed Fabric Extender Vpc Topology

    1-Gigabit Ethernet uplink interfaces. Figure 10: Dual Homed Fabric Extender vPC Topology The Cisco Nexus device can support up to 12 configured dual homed Fabric Extenders with this topology. A maximum of 576 single homed servers can be connected to this configuration.
  • Page 126: Peer-Keepalive Link And Messages

    For example, if the timeout value is 3 seconds and the hold-timeout value is 5 seconds, the timeout period starts after 5 seconds. We recommend that you configure the vPC peer-keepalive link on the Cisco Nexus device to run in the Note management VRF using the mgmt 0 interfaces.
  • Page 127: Configuration Parameters That Must Be Identical

    ◦ Root Guard • For the Fabric Extender vPC topology, all the interface level parameters mentioned above should be identically configured for host interface from both the switches. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 128: Configuration Parameters That Should Be Identical

    ◦ VLANs (Rapid PVST+) To ensure that all the configuration parameters are compatible, we recommend that you display the configurations for each vPC peer switch once you configure the vPC. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 129: Graceful Type-1 Check

    Per-VLAN Consistency Check Beginning with Cisco NX-OS Release 5.0(2)N2(1), some Type-1 consistency checks are performed on a per-VLAN basis when spanning tree is enabled or disabled on a VLAN. VLANs that do not pass the consistency check are brought down on both the primary and secondary switches while other VLANs are not affected.
  • Page 130: Vpc Number

    When you configure the vPC peer link, the vPC peer switches negotiate that one of the connected switches is the primary switch and the other connected switch is the secondary switch. By default, the Cisco NX-OS software uses the lowest MAC address to elect the primary switch. The software takes different actions on each switch—that is, the primary and secondary—only in certain failover conditions.
  • Page 131: Vpc Interactions With Other Features

    Apply this same configuration to the other vPC peer device. Before You Begin To configure a track list to switch over vPC to the remote peer when all related interfaces fail: Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 132: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    Enters vPC domain configuration. Step 10 switch(config-vpc-domain)# track number Adds the track object to the vPC domain. Step 11 switch(config)# show vpc brief (Optional) Displays the track object. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 133: Vpc And Lacp

    When you first bring up the vPC functionality, STP reconverges. STP treats the vPC peer link as a special link and always includes the vPC peer link in the STP active topology. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 134: Cfsoe

    # ip arp synchronize CFSoE The Cisco Fabric Services over Ethernet (CFSoE) is a reliable state transport mechanism that you can use to synchronize the actions of the vPC peer devices. CFSoE carries messages and packets for many features linked with vPC, such as STP and IGMP.
  • Page 135: Vpc Peer Switch

    The vPC peer switch feature addresses performance concerns around STP convergence. This feature allows a pair of Cisco Nexus devices to appear as a single STP root in the Layer 2 topology. This feature eliminates the need to pin the STP root to the vPC primary switch and improves vPC convergence if the vPC primary switch fails.
  • Page 136: Configuring Vpcs

    Enters global configuration mode. Step 2 switch(config)# feature vpc Enables vPCs on the switch. Step 3 switch# show feature (Optional) Displays which features are enabled on the switch. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 137: Disabling Vpcs

    Disabling vPCs You can disable the vPC feature. Note When you disable the vPC feature, the Cisco Nexus device clears all the vPC configurations. SUMMARY STEPS 1. switch# configure terminal 2. switch(config)# no feature vpc 3. (Optional) switch# show feature 4.
  • Page 138: Creating A Vpc Domain

    You can configure the destination IP for the peer-keepalive link that carries the keepalive messages. Optionally, you can configure other parameters for the keepalive messages. The Cisco NX-OS software uses the peer-keepalive link between the vPC peers to transmit periodic, configurable keepalive messages. You must have Layer 3 connectivity between the peer devices to transmit Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1)
  • Page 139: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    The management ports and VRF are the defaults. max-throughput | min-delay | min-monetary-cost | normal} | tos-byte tos-byte-value} | source ipaddress | vrf {name | management vpc-keepalive}] Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 140: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    : Vlan123 --Last update from peer : (0) seconds, (524) msec vPC Keep-alive parameters --Destination : 123.1.1.1 --Keepalive interval : 1000 msec --Keepalive timeout : 5 seconds Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 141: Creating A Vpc Peer Link

    Step 3 switch(config-if)# vpc peer-link Configures the selected EtherChannel as the vPC peer link, and enters the vpc-domain configuration mode. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 142: Checking The Configuration Compatibility

    After you have configured the vPC peer link on both vPC peer switches, check that the configurations are consistent on all vPC interfaces. Beginning with Cisco NX-OS Release 5.0(2)N1(1), the The following QoS parameters support Type 2 Note consistency checks: •...
  • Page 143: Enabling Vpc Auto-Recovery

    Enters vpc-domain configuration mode for an existing vPC domain. Step 3 switch(config-vpc-domain)# auto-recovery Enables the auto-recovery feature and sets the reload delay reload-delay delay period. The default is disabled. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 144: Configuring The Restore Time Delay

    Configuring the Restore Time Delay Beginning with Cisco NX-OS Release 5.0(3)N1(1), youYou can configure a restore timer that delays the vPC from coming back up until after the peer adjacency forms and the VLAN interfaces are back up. This feature avoids packet drops if the routing tables fail to converge before the vPC is once again passing traffic.
  • Page 145: Excluding Vlan Interfaces From Shutting Down A Vpc Peer Link Fails

    This example shows how to keep the interfaces on VLAN 10 up on the vPC peer switch if a peer link fails: switch# configure terminal switch(config)# vpc domain 5 switch(config-vpc-domain)# dual-active exclude interface-vlan 10 switch(config-vpc-domain)# Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 146: Configuring The Vrf Name

    VLAN that is not already in use. SUMMARY STEPS 1. switch# configure terminal 2. switch(config)# vpc bind-vrf vrf-name vlan vlan-id Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 147: Enabling Layer 3 Forwarding To The Gateway Mac Address Of The Vpc

    Step 3 switch(config-vpc-domain))# peer-gateway Enables Layer 3 forwarding for packets destined to the gateway range MAC address of the virtual Port Channel (vPC). Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 148: Suspending Orphan Ports On A Secondary Switch In A Vpc Topology

    Step 4 switch(config-if)# exit Exits interface configuration mode. Step 5 switch# show vpc orphan-port (Optional) Displays the orphan port configuration. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 149: Creating An Etherchannel Host Interface

    Creating an EtherChannel Host Interface To connect to a downstream server from a Cisco Nexus Fabric Extender you can create a EtherChannel host interface. An EtherChannel host interface can have only one host interface as a member depending on the fabric extender model.
  • Page 150: Moving Other Port Channels Into A Vpc

    SUMMARY STEPS 1. switch# configure terminal 2. switch(config)# interface port-channel channel-number 3. switch(config-if)# vpc number 4. (Optional) switch# show vpc brief 5. (Optional) switch# copy running-config startup-config Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 151: Manually Configuring A Vpc Domain Mac Address

    Configuring the system address is an optional configuration step. Before You Begin Ensure that you have enabled the vPC feature. You must configure both switches on either side of the vPC peer link. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 152: Manually Configuring The System Priority

    Before You Begin Ensure that you have enabled the vPC feature. You must configure both switches on either side of the vPC peer link. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 153: Manually Configuring A Vpc Peer Switch Role

    Manually Configuring a vPC Peer Switch Role By default, the Cisco NX-OS software elects a primary and secondary vPC peer switch after you configure the vPC domain and both sides of the vPC peer link. However, you may want to elect a specific vPC peer switch as the primary switch for the vPC.
  • Page 154: Configuring The Vpc Peer Switch

    You can configure a pure vPC peer switch topology using the peer-switch command and then you set the best possible (lowest) spanning tree bridge priority value. Note The values you apply for the spanning tree priority must be identical on both vPC peers. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 155: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    Saves the change persistently through reboots and restarts by copying the running configuration to the startup configuration. This example shows how to configure a pure vPC peer switch topology: switch# configure terminal Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 156: Configuring A Hybrid Vpc Peer Switch Topology

    4. switch(config-pseudo)# vlan vlan-id root priority priority 5. switch(config-pseudo)# exit 6. switch(config)# vpc domain domain-id 7. switch(config-vpc-domain)# peer-switch 8. switch(config-vpc-domain)# exit 9. (Optional) switch(config)# show spanning-tree summary 10. (Optional) switch(config)# copy running-config startup-config Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 157: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    1 designated priority 8192 switch(config-pseudo)# vlan 1 root priority 4096 switch(config-pseudo)# exit switch(config)# vpc domain 5 switch(config-vpc-domain)# peer-switch switch(config-vpc-domain)# exit switch(config)# copy running-config startup-config Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 158: Verifying The Vpc Configuration

    For information about the switch output, see the Command Reference for your Cisco Nexus Series switch. Viewing the Graceful Type-1 Check Status This example shows how to display the current status of the graceful Type-1 consistency check:...
  • Page 159: Viewing A Global Type-1 Inconsistency

    Number of vPCs configured Peer Gateway : Disabled Dual-active excluded VLANs Graceful Consistency Check : Enabled vPC Peer-link status --------------------------------------------------------------------- Port Status Active vlans ---- ------ -------------------------------------------------- 1-10 Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 160: Viewing An Interface-Specific Type-1 Inconsistency

    Type-2 consistency status : success vPC role : primary Number of vPCs configured Peer Gateway : Disabled Dual-active excluded VLANs Graceful Consistency Check : Enabled vPC Peer-link status --------------------------------------------------------------------- Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 161: Viewing A Per-Vlan Consistency Status

    : peer is alive Configuration consistency status: success Per-vlan consistency status : failed Type-2 consistency status : success vPC role : secondary Number of vPCs configured Peer Gateway : Disabled Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 162: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    STP Loopguard success 0-4095 STP Bridge Assurance success 0-4095 STP Port Type, Edge success 0-4095 BPDUFilter, Edge BPDUGuard STP MST Simulate PVST success 0-4095 Pass Vlans 0-4,6-4095 Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 163: Vpc Example Configurations

    4. Create a Fabric Extender identifier (for example, "100"). 5. Configure the fabric EtherChannel links for the Fabric Extender 100. 6. Configure each host interface port on the Fabric Extender 100 on both Cisco Nexus devices as for all the other steps.
  • Page 164: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    CiscoNexus-1(config-if)# fex associate 100 CiscoNexus-1(config-if)# exit Step 6 Configure each host interface port on the Fabric Extender 100 on both Cisco Nexus devices as for all the other steps. CiscoNexus-1(config)# interface ethernet 100/1/1-48 CiscoNexus-1(config-if)# switchport mode access CiscoNexus-1(config-if)# switchport access vlan 50...
  • Page 165: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    Extender NX-2000-100. You must repeat these steps on its vPC peer, CiscoNexus-2, which is connected to the Fabric Extender NX-2000-101. Before You Begin Ensure that the Cisco Nexus 2000 Series Fabric Extenders NX-2000-100 and NX-2000-101 are attached and online. SUMMARY STEPS 1.
  • Page 166: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    Configure the fabric EtherChannel links for the Fabric Extender NX-2000-100. CiscoNexus-1(config)# interface ethernet 1/20-21 CiscoNexus-1(config-if)# channel-group 100 CiscoNexus-1(config-if)# exit CiscoNexus-1(config)# interface port-channel 100 CiscoNexus-1(config-if)# switchport mode fex-fabric CiscoNexus-1(config-if)# fex associate 100 CiscoNexus-1(config-if)# exit Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 167: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    Table 9: Default vPC Parameters Parameters Default vPC system priority 32667 vPC peer-keepalive message Disabled vPC peer-keepalive interval 1 second vPC peer-keepalive timeout 5 seconds vPC peer-keepalive UDP port 3200 Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 168: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    Configuring Virtual Port Channels vPC Default Settings Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 169: Chapter

    • Licensing Requirements for Enhanced vPC, page 152 • Configuring Enhanced vPCs, page 152 • Verifying Enhanced vPCs, page 153 • Enhanced vPC Example Configuration, page 157 Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 170: Information About Enhanced Vpcs

    Enhanced vPC is compatible with Layer 3 features on the switch. Supported and Unsupported Topologies Enhanced vPC supports the following topologies: • A single homed server connected to a single FEX Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 171: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    The scalability of enhanced vPC is similar to that of the dual homed FEX topology. Each Cisco Nexus device supports up to 24 FEXs with Layer 2 configuration or Layer 3 configuration. In a dual homed FEX topology, such as that in enhanced vPC, each FEX is managed by two switches, so the pair together can support 24 FEXs.
  • Page 172: Licensing Requirements For Enhanced Vpc

    This feature does not require a license. Any feature not included in a license package is bundled with the Cisco NX-OS system images and is provided at no extra charge to you. For a complete explanation of the Cisco NX-OS licensing scheme, see the Cisco NX-OS Licensing Guide.
  • Page 173: Verifying Enhanced Vpcs

    FEX topology, and is described in the documentation for dual homed FEX. In addition to the global consistency verification, enhanced vPCs require interface level verification using tasks described in this section. Use the following commands to verify the enhanced vPC configuration and consistency: Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 174: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    Displays the status and configuration of the specified port channel member port. Example: Enter this command on both peer switches and verify the status of switch-1# show interface Ethernet110/1/1 the ports. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 175: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    2. (Optional) show interface type/slot DETAILED STEPS Command or Action Purpose Step 1 show port-channel summary Displays a summary of the port channel interfaces. Example: switch-1# show port-channel summary Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 176: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    For enhanced vPCs, you must ensure consistency of the port mode and the shared VLAN in the port channel interface configuration. SUMMARY STEPS 1. show vpc consistency-parameters port-channel channel-number Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 177: Enhanced Vpc Example Configuration

    For more information about configuration synchronization, see the operations guide for your device. Before You Begin Ensure that the Cisco Nexus Fabric Extenders FEX101 and FEX102 are attached and online. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 178: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    1, 10-20 switch-1(config-if)# vpc peer-link switch-2(config)# interface eth1/1-2 switch-2(config-if)# channel-group 1 mode active switch-2(config-if)# interface Po1 switch-2(config-if)# switchport mode trunk switch-2(config-if)# switchport trunk allowed vlan 1, 10-20 Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 179: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    10 switch-2(config)# interface eth101/1/1, eth101/1/2 switch-2(config-if)# channel-group 2 mode active switch-2(config-if)# interface eth102/1/1, eth102/1/2 switch-2(config-if)# channel-group 2 mode active switch-2(config-if)# int po2 switch-2(config-if)# switchport access vlan 10 Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 180: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    Configuring Enhanced Virtual Port Channels Enhanced vPC Example Configuration Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 181: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    STP frames, which are called Bridge Protocol Data Units (BPDUs), at regular intervals. Switches do not forward these frames but use the frames to construct a loop-free path. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 182: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    Bridge Priority Value The bridge priority is a 4-bit value when the extended system ID is enabled. In Cisco NX-OS, the extended system ID is always enabled; you cannot disable the extended system ID. Note Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1)
  • Page 183: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    4096. Only the following values are possible: • 0 • 4096 • 8192 • 12288 • 16384 • 20480 • 24576 • 28672 • 32768 Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 184: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    • A root port is selected. This is the port providing the best path from the bridge to the root bridge. • Ports included in the spanning tree are selected. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 185: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    By changing the STP port priority on the fiber-optic port to a higher priority (lower numerical value) than the root port, the fiber-optic port becomes the new root port. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 186: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    • Edge ports—When you configure a port as an edge port on an RSTP switch, the edge port immediately transitions to the forwarding state. (This immediate transition was previously a Cisco-proprietary feature named PortFast.) You should only configure on ports that connect to a single end station as edge ports.
  • Page 187: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    Another important change is that the Rapid PVST+ BPDU is type 2, version 2, which makes it possible for the switch to detect connected legacy (802.1D) bridges. The BPDU for 802.1D is version 0. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 188: Cisco Nexus 5000 Series Nx-Os Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1

    This proposal/agreement handshake is initiated only when a non-edge port moves from the blocking to the forwarding state. The handshaking process then proliferates step-by-step throughout the topology. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 189: Protocol Timers

    In a stable topology with consistent port roles throughout the network, Rapid PVST+ ensures that every root port and designated port immediately transition to the forwarding state while all alternate and backup ports Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 190: Port States

    When you enable Rapid PVST+, every port in the software, VLAN, and network goes through the blocking state and the transitory states of learning at power up. If properly configured, each LAN port stabilizes to the forwarding or blocking state. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 191: Blocking State

    A LAN port in the forwarding state forwards frames. The LAN port enters the forwarding state from the learning state. A LAN port in the forwarding state performs as follows: Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 192: Disabled State

    When the switch receives a proposal message on one of its ports and that port is selected as the new root port, Rapid PVST+ forces all other ports to synchronize with the new root information. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 193: Processing Superior Bpdu Information

    Rapid PVST+ sets the port to the blocking state and sends an agreement message. The designated port continues sending BPDUs with the proposal flag set until the forward-delay timer expires. At that time, the port transitions to the forwarding state. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 194: Processing Inferior Bpdu Information

    LAN interface. If a loop occurs, STP considers the port cost when selecting a LAN interface to put into the forwarding state. Table 13: Default Port Cost Bandwidth Short Path-Cost Method of Port Long Path-Cost Method of Port Cost Cost 10 Mbps 2,000,000 Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 195: Port Priority

    When you connect a Cisco switch to a non-Cisco switch through an 802.1Q trunk, the Cisco switch combines the STP instance of the 802.1Q VLAN of the trunk with the STP instance of the non-Cisco 802.1Q switch. However, all per-VLAN STP information that is maintained by Cisco switches is separated by a cloud of non-Cisco 802.1Q switches.
  • Page 196: Rapid Pvst+ Interoperation With 802.1S Mst

    Once you enable Rapid PVST+ on the switch, you must enable Rapid PVST+ on the specified VLANs. Rapid PVST+ is the default STP mode. You cannot simultaneously run MST and Rapid PVST+. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 197: Enabling Rapid Pvst+ Per Vlan

    Rapid PVST+ is enabled by default on the default VLAN and on all VLANs that you create. SUMMARY STEPS 1. switch# configure terminal 2. switch(config)# spanning-tree vlan-range 3. (Optional) switch(config)# no spanning-tree vlan-range Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 198: Configuring The Root Bridge Id

    Caution The root bridge for each instance of STP should be a backbone or distribution switch. Do not configure an access switch as the STP primary root. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 199: Configuring A Secondary Root Bridge

    You configure more than one switch in this manner to have multiple backup root bridges. Enter the same network diameter and hello time values that you used when configuring the primary root bridge. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 200: Configuring The Rapid Pvst+ Port Priority

    LAN port is configured as a trunk port. SUMMARY STEPS 1. switch# configure terminal 2. switch(config)# interface type slot/port 3. switch(config-if)# spanning-tree [vlan vlan-list] port-priority priority Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 201: Configuring The Rapid Pvst+ Path-Cost Method And Port Cost

    Enters global configuration mode. Step 2 switch(config)# spanning-tree pathcost Selects the method used for Rapid PVST+ path-cost calculations. The default method is the short method. method {long | short} Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 202: Configuring The Rapid Pvst+ Bridge Priority Of A Vlan

    Configures the bridge priority of a VLAN. Valid values are 0, 4096, vlan-range priority value 8192, 12288, 16384, 20480, 24576, 28672, 32768, 36864, 40960, 45056, Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 203: Configuring The Rapid Pvst+ Hello Time For A Vlan

    5 hello-time 7 Configuring the Rapid PVST+ Forward Delay Time for a VLAN You can configure the forward delay time per VLAN when using Rapid PVST+. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 204: Configuring The Rapid Pvst+ Maximum Age Time For A Vlan

    6 to 40 seconds, and the default is 20 seconds. This example shows how to configure the maximum aging time for a VLAN: switch# configure terminal switch(config)# spanning-tree vlan 5 max-age 36 Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 205: Specifying The Link Type

    You can restart the protocol negotiation (force the renegotiation with neighboring switches) on the entire switch or on specified interfaces. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 206: Verifying The Rapid Pvst+ Configuration

    Forward Delay 15 sec Interface Role Sts Cost Prio.Nbr Type ---------------- ---- --- --------- -------- -------------------------------- Eth1/3 Root FWD 2 128.131 P2p Peer(STP) veth1/1 Desg FWD 2 128.129 Edge P2p Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 207: Configuring Multiple Spanning Tree

    • Rapid per-VLAN spanning tree (Rapid PVST+) IEEE 802.1w defined the Rapid Spanning Tree Protocol (RSTP) and was incorporated into IEEE 802.1D. • IEEE 802.1s defined MST and was incorporated into IEEE 802.1Q. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 208: Mst Regions

    BPDU that the IST sends. Because the MST BPDU carries information for all instances, the number of BPDUs that need to be processed to support MSTIs is significantly reduced. Figure 21: MST BPDU with M-Records for MSTIs Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 209: Mst Configuration Information

    An MSTI is local to the region; for example, MSTI 9 in region A is independent of MSTI 9 in region B, even if regions A and B are interconnected. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 210: Spanning Tree Operation Within An Mst Region

    The root of the subtree is the CIST regional root. The MST region appears as a virtual switch to adjacent STP switches and MST regions. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 211: Mst Terminology

    The MST terminology is as follows: • The CIST root is the root bridge for the CIST, which is the unique instance that spans the whole network. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 212: Hop Count

    STP bridge or receives an agreement proposal from an MST bridge with a different configuration or a Rapid PVST+ bridge. This definition allows two ports that are internal to a region to share a segment Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 213: Spanning-Tree Dispute Mechanism

    Switch A blocks (or keeps blocking) its port, which prevents the bridging loop. The block is shown as an STP dispute. Figure 24: Detecting a Unidirectional Link Failure Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 214: Port Cost And Port Priority

    MST configuration. MST interoperates with the Cisco prestandard Multiple Spanning Tree Protocol (MSTP) whenever it Note receives prestandard MSTP on an MST port; no explicit configuration is necessary.
  • Page 215: Interoperability With Rapid Pvst+: Understanding Pvst Simulation

    Also, having two different spanning-tree modes on Virtual Port Channel (vPC) peer switches is an inconsistency, so this operation is disruptive. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 216: Entering Mst Configuration Mode

    When you are working in MST configuration mode, note the difference between the exit and abort commands. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 217: Specifying The Mst Name

    You configure a region name on the bridge. For two or more bridges to be in the same MST region, they must have the identical MST name, VLAN-to-instance mapping, and MST revision number. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 218: Specifying The Mst Configuration Revision Number

    Enters MST configuration submode. Step 3 switch(config-mst)# revision version Specifies the revision number for the MST region. The range is from 0 to 65535, and the default value is 0. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 219: Specifying The Configuration On An Mst Region

    To specify a VLAN series, enter a comma; for example, enter the instance 1 vlan 10, 20, 30 command to map VLANs 10, 20, and 30 to MST instance Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 220: Mapping And Unmapping Vlans To Mst Instances

    You cannot disable an MSTI. For two or more bridges to be in the same MST region, they must have the identical MST name, VLAN-to-instance mapping, and MST revision number. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 221: Mapping Secondary Vlans To Same Msti As Primary Vlans For Private Vlans

    When you are working with private VLANs on the system, all secondary VLANs must be in the same MSTI and their associated primary VLAN. SUMMARY STEPS 1. switch# configure terminal 2. switch(config)# spanning-tree mst configuration 3. switch(config-mst)# private-vlan synchronize Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 222: Configuring The Root Bridge

    SUMMARY STEPS 1. switch# configure terminal 2. switch(config)# spanning-tree mst instance-id root {primary | secondary} [diameter dia [hello-time hello-time]] 3. (Optional) switch(config)# no spanning-tree mst instance-id root Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 223: Configuring A Secondary Root Bridge

    2. switch(config)# spanning-tree mst instance-id root {primary | secondary} [diameter dia [hello-time hello-time]] 3. (Optional) switch(config)# no spanning-tree mst instance-id root DETAILED STEPS Command or Action Purpose Step 1 switch# configure terminal Enters global configuration mode. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 224: Configuring The Port Priority

    Specifies an interface to configure, and enters interface configuration | {port-channel number}} mode. Step 3 switch(config-if)# spanning-tree mst Configures the port priority as follows: instance-id port-priority priority Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 225: Configuring The Port Cost

    Specifies an interface to configure, and enters interface configuration mode. slot/port} | {port-channel number}} Step 3 switch(config-if)# spanning-tree mst Configures the cost. instance-id cost [cost | auto] Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 226: Configuring The Switch Priority

    • For instance-id, you can specify a single instance, a range of instances separated by a hyphen, or a series of instances separated by a comma. The range is from 1 to 4094. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 227: Configuring The Hello Time

    These messages mean that the switch is alive. For seconds, the range is from 1 to 10, and the default is 2 seconds. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 228: Configuring The Forwarding-Delay Time

    You set the maximum-aging timer for all MST instances on the switch with one command (the maximum age time only applies to the IST). SUMMARY STEPS 1. switch# configure terminal 2. switch(config)# spanning-tree mst max-age seconds Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 229: Configuring The Maximum-Hop Count

    1 to 255, and the default value is 20 hops. This example shows how to set the maximum hops to 40: switch# configure terminal switch(config)# spanning-tree mst max-hops 40 Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 230: Configuring Pvst Simulation Globally

    2. switch(config)# interface {{type slot/port} | {port-channel number}} 3. switch(config-if)# spanning-tree mst simulate pvst disable 4. switch(config-if)# spanning-tree mst simulate pvst 5. switch(config-if)# no spanning-tree mst simulate pvst Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 231: Specifying The Link Type

    If you set the link to shared, STP reverts to 802.1D. SUMMARY STEPS 1. switch# configure terminal 2. switch(config)# interface type slot/port 3. switch(config-if)# spanning-tree link-type {auto | point-to-point | shared} Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 232: Restarting The Protocol

    [interface-num | port-channel]] interfaces. This example shows how to restart MST on the Ethernet interface on slot 2, port 8: switch# clear spanning-tree detected-protocol interface ethernet 2/8 Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 233: Verifying The Mst Configuration

    This example shows how to display the current MST configuration: switch# show spanning-tree mst configuration % Switch is not in mst mode Name [mist-attempt] Revision Instances configured 2 Instance Vlans mapped -------- --------------------------------------------------------------------- 1-12,14-41,43-4094 13,42 Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 234 Configuring Multiple Spanning Tree Verifying the MST Configuration Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 235: Configuring Stp Extensions

    Overview, page 215 Overview Cisco has added extensions to Spanning Tree Protocol (STP) that make convergence more efficient. In some cases, even though similar functionality may be incorporated into the IEEE 802.1w Rapid Spanning Tree Protocol (RSTP) standard, we recommend using these extensions. All of these extensions can be used with both RPVST+ and Multiple Spanning Tree Protocol (MST).
  • Page 236: Spanning Tree Network Ports

    When you configure BPDU Guard globally, it is effective only on operational spanning tree edge ports. In a valid configuration, LAN edge interfaces do not receive BPDUs. A BPDU that is received by an edge LAN Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 237: Understanding Bpdu Filtering

    BPDUs. If this port receives any BPDUs, the port returns to the spanning tree normal port state and BPDU Filtering is disabled. Default Enabled Disabled Disabled Default Disabled Enabled/Disabled Disabled Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 238: Understanding Loop Guard

    You can enable Loop Guard on a per-port basis. When you enable Loop Guard on a port, it is automatically applied to all of the active instances or VLANs to which that port belongs. When you disable Loop Guard, it is disabled for the specified ports. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 239: Understanding Root Guard

    These ports can be connected to any type of device. You can configure the port type either globally or per interface. By default, the spanning tree port type is normal. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 240: Configuring Spanning Tree Edge Ports On Specified Interfaces

    This command has four states: • spanning-tree port type edge—This command explicitly enables edge behavior on the access port. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 241 This example shows how to configure the Ethernet access interface 1/4 to be a spanning tree edge port: switch# configure terminal switch(config)# interface ethernet 1/4 switch(config-if)# spanning-tree port type edge Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 242: Configuring Spanning Tree Network Ports On Specified Interfaces

    Configures the specified interfaces to be spanning network ports. If network you enable Bridge Assurance, it automatically runs on network ports. By default, spanning tree ports are normal port types. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 243: Enabling Bpdu Guard Globally

    You can configure BPDU Guard on specified interfaces as follows: • spanning-tree bpduguard enable—Unconditionally enables BPDU Guard on the interface. • spanning-tree bpduguard disable—Unconditionally disables BPDU Guard on the interface. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 244: Enabling Bpdu Filtering Globally

    If an edge port with BPDU Filtering enabled receives a BPDU, it loses its operation status and as edge port and resumes the regular STP transitions. However, this port maintains it configuration as an edge port. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 245: Enabling Bpdu Filtering On Specified Interfaces

    BPDU it receives and goes to forwarding. You can enter this command to override the port configuration on specified interfaces. This command has three states: Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 246 This example shows how to explicitly enable BPDU Filtering on the Ethernet spanning tree edge port 1/4: switch# configure terminal switch (config)# interface ethernet 1/4 switch(config-if)# spanning-tree bpdufilter enable Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 247: Enabling Loop Guard Globally

    Both Loop Guard and Root Guard enabled on an interface apply to all VLANs to which that interface belongs. Entering the Loop Guard command for the specified interface overrides the global Loop Guard command. Note Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 248: Verifying The Stp Extension Configuration

    [all] Displays the current status of spanning tree on the switch. show spanning-tree [options] Displays selected detailed information for the current spanning tree configuration. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 249: Configuring Flex Links

    C. When port 1 comes back up, it goes into standby mode and does not forward traffic; port 2 continues forwarding traffic. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 250: Guidelines And Limitations For Flex Link

    • You can configure only one Flex Link backup link for any active link and it must be a different interface from the active interface. • An interface can belong to only one Flex Link pair; it can be a backup link for only one active link. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 251: Default Settings For Flex Link

    • Fabric path core interfaces (Layer 2 multipath) Default Settings for Flex Link Table 15: Flex Link Default Parameter Settings Parameter Definition Multicast Fast-Convergence Disabled Preemption mode Preemption delay 35 seconds Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 252: Configuring Flex Links

    • preemption—Configures a preemption scheme for a backup interface pair. • delay delay-time—Specifies the preemption delay. The delay-time range is from 1 to 300 seconds. The default is 35 seconds. • mode—Specifies the preemption mode. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 253: Configuring Flex Link Preemption

    Po301 00:00:12 00:04:50 Configuring Flex Link Preemption You can configure a preemption scheme for a pair of Flex Links. Before You Begin Enable the Flex Link feature. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 254 35 seconds. delay delay-time Note Setting a delay time only works with forced and bandwidth modes. Step 6 switch(config-if) # end (Optional) Return to privileged EXEC mode. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 255: Verifying Flex Link Configuration

    Displays the running or startup configuration for backup interfaces. show startup-config backup show running-config flexlink Displays the running or startup configuration for flex link interfaces. show startup-config flexlink Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 256: Flex Link Configuration Examples

    This example shows the running configuration of Flex Link: switch# show running-config flexlink !Command: show running-config flexlink !Time: Thu Jan 1 03:21:12 2011 version 5.0(3)N2(1) feature flexlink Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 257 Active Down/Backup Up Preemption Mode : forced Preemption Delay : 35 seconds (default) (scheduled) Multicast Fast Convergence : Off Bandwidth : 20000000 Kbit (port-channel300), 10000000 Kbit (port-channel301) Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 258 Configuring Flex Links Flex Link Configuration Examples Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 259: Chapter

    Use the reinit option to set the length of time (1 to 10 seconds) to wait before system-capabilities | performing LLDP initialization on any interface. The default value is 2 seconds. system-description | system-name}} Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 260: Configuring Interface Lldp

    2. switch(config)# interface type slot/port 3. switch(config-if)# [no] lldp {receive | transmit} 4. (Optional) switch# show lldp {interface | neighbors [detail | interface | system-detail] | timers | traffic} Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 261 LLDP TLV Length: 55 LLDP TLV type:LLDP Organizationally Specific LLDP TLV Length: 5 LLDP TLV type:END of LLDPDU LLDP TLV Length: 0 Remote Peers Information on interface Eth1/33 Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 262 LLDP traffic statistics: Total frames out: 8464 Total Entries aged: 6 Total frames in: 6342 Total frames received in error: 2 Total frames discarded: 2 Total TLVs unrecognized: 0 Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 263: Chapter

    Configuring Static MAC Addresses You can configure static MAC addresses for the switch. These addresses can be configured in interface configuration mode or in VLAN configuration mode. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 264: Configuring The Aging Time For The Mac Table

    Enters global configuration mode. Step 2 switch(config)# mac-address-table Specifies the time before an entry ages out and is discarded from the MAC aging-time seconds [vlan vlan_id] address table. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 265: Clearing Dynamic Addresses From The Mac Table

    Use one of the following commands to verify the configuration: Table 16: MAC Address Configuration Verification Commands Command Purpose show mac-address-table aging-time Displays the MAC address aging time for all VLANs defined in the switch. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 266 Port Down Action Mac Loop Detect : enabled switch# configure terminal switch(config)# no mac address-table loop-detect port-down switch(config)# show mac address-table loop-detect Port Down Action Mac Loop Detect : disabled Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 267: Configuring Igmp Snooping

    Layer 2 forwarding decisions. Cisco NX-OS supports IGMPv2 and IGMPv3. IGMPv2 supports IGMPv1, and IGMPv3 supports IGMPv2. Although not all features of an earlier version of IGMP are supported, the features related to membership query and membership report messages are supported for all IGMP versions.
  • Page 268: Igmpv1 And Igmpv2

    IGMPv1 does not provide an explicit IGMP leave message, so the software must rely on the membership message timeout to indicate that no hosts remain that want to receive multicast data for a particular group. Cisco NX-OS ignores the configuration of the last member query interval when you enable the fast leave Note feature because it does not check for remaining hosts.
  • Page 269: Igmpv3

    IGMP Forwarding The control plane of the Cisco Nexus device is able to detect IP addresses but forwarding occurs using the MAC address only. When a host connected to the switch wants to join an IP multicast group, it sends an unsolicited IGMP join message, specifying the IP multicast group to join.
  • Page 270: Configuring Igmp Snooping Parameters

    The default is enabled. Multicast router Configures a static connection to a multicast router. The interface to the router must be in the selected VLAN. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 271 11. switch(config-vlan)# ip igmp snooping mrouter vpc-peer-link 12. switch(config-vlan)# ip igmp snooping static-group group-ip-addr [source source-ip-addr] interface interface DETAILED STEPS Command or Action Purpose Step 1 switch# configure terminal Enters global configuration mode. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 272 Configures an interface belonging to a VLAN as a static member of a static-group group-ip-addr [source multicast group. You can specify the interface by type and number. source-ip-addr] interface interface Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 273: Verifying The Igmp Snooping Configuration

    Number of router-ports: 0 Number of groups: 0 IGMP Snooping information for vlan 5 IGMP snooping enabled IGMP querier present, address: 192.0.2.1, version: 3 Querier interval: 125 secs Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 274 Switch-querier enabled, address 192.0.2.1, currently running Explicit tracking enabled Fast leave enabled Report suppression enabled Router port detection using PIM Hellos, IGMP Queries Number of router-ports: 1 Number of groups: 1 Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 275: Configuring Mvr

    IGMP join and leave messages. IGMP leave messages from an MVR group are handled according to the IGMP configuration of the VLAN on which the leave message is received. If IGMP fast leave is enabled Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 276: Mvr Interoperation With Other Features

    This feature does not require a license. Any feature not included in a license package is bundled with the Cisco NX-OS system images and is provided at no extra charge to you. For a complete explanation of the Cisco NX-OS licensing scheme, see the Cisco NX-OS Licensing Guide.
  • Page 277: Default Mvr Settings

    4. switch(config)# [no] mvr-group addr[/mask] [count groups] [vlan vlan-id] 5. (Optional) switch(config)# end 6. (Optional) switch# clear mvr counters [source-ports | receiver-ports] 7. (Optional) switch# show mvr 8. (Optional) switch# copy running-config startup-config Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 278 192.0.2.1 count 4 switch(config-mvr)# mvr-group 192.0.2.240/28 vlan 101 switch(config-mvr)# mvr-group 192.0.2.6 vlan 340 switch(config-mvr)# end switch# show mvr MVR Status : enabled Global MVR VLAN : 100 Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 279: Configuring Mvr Interfaces

    If you attempt to configure a non-MVR port with MVR characteristics, the configuration is cached and does not take effect until the port becomes an MVR port. The default port mode is non-MVR. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 280: Verifying The Mvr Configuration

    Use the following commands to verify the MVR configuration: Command Description show mvr Displays the MVR subsystem configuration and status. show mvr groups Displays the MVR group configuration. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 281 Po206 RECEIVER ACTIVE 100-101,340 Po207 RECEIVER ACTIVE 100-101,340 Po208 RECEIVER ACTIVE 2000-2001 Eth1/9 SOURCE ACTIVE Eth1/10 RECEIVER ACTIVE 100-101,340 Eth2/2 RECEIVER ACTIVE 100-101,340 Eth102/1/1 RECEIVER ACTIVE 100-101,340 Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 282 This example shows how to display all MVR source ports on all interfaces: switch# show mvr source-ports Port MVR-VLAN Status ------------ -------- -------- Po10 ACTIVE Eth1/9 ACTIVE Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 283: Information About Traffic Storm Control

    When the ingress traffic reaches the traffic storm control level that is configured on the port, traffic storm control drops the traffic until the interval ends. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 284 10-microsecond interval, traffic storm control drops all exceeding multicast traffic until the end of the interval. By default, Cisco NX-OS takes no corrective action when traffic exceeds the configured level. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1)
  • Page 285: Guidelines And Limitations For Traffic Storm Control

    The result of the command is partial success in some cases. • In the Cisco Nexus 5000 switch, storm-control does not distinguish between IP, non-IP, registered, or unregistered multicast traffic. All multicast traffic is subject to a single-multicast storm control policer when configured.
  • Page 286: Configuring Traffic Storm Control

    Note Traffic storm control uses a 10-microsecond interval that can affect the operation of traffic storm control. show running-config interface Displays the traffic storm control configuration. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 287: Traffic Storm Control Example Configuration

    The following table lists the default settings for traffic storm control parameters. Table 18: Default Traffic Storm Control Parameters Parameters Default Traffic storm control Disabled Threshold percentage Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 288 Configuring Traffic Storm Control Default Settings for Traffic Storm Control Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 289: Information About The Cisco Nexus 2000 Series Fabric Extender

    Information About the Cisco Nexus 2000 Series Fabric Extender The Cisco Nexus 2000 Series Fabric Extender, also known as FEX, is a highly scalable and flexible server networking solution that works with Cisco Nexus Series devices to provide high-density, low-cost connectivity for server aggregation.
  • Page 290: Fabric Extender Terminology

    Configuring the Fabric Extender Fabric Extender Terminology The Fabric Extender integrates with its parent switch, which is a Cisco Nexus Series device, to allow automatic provisioning and configuration taken from the settings on the parent device. This integration allows large numbers of servers and hosts to be supported by using the same feature set as the parent device with a single management domain.
  • Page 291: Fabric Extender Features

    • You can connect only virtual switches that leverages a link redundancy mechanism not dependent on spanning tree such as Cisco FlexLink or vPC (with the BPDU Filter enabled) to a Fabric Extender host interface. Because spanning tree is not used to eliminate loops, you should ensure a loop-free topology below the Fabric Extender host interfaces.
  • Page 292: Vlans And Private Vlans

    The vPC can provide multipath connections, which allow you to create redundancy between the nodes on your network. A port channel between two FEXs that are connected to the same Cisco Nexus device is not supported. Note Virtual port channels (vPCs) cannot span two different FEXs when connected to the same Cisco Nexus device.
  • Page 293: Fibre Channel Over Ethernet Support

    /www.cisco.com/en/US/products/ps9670/products_installation_and_configuration_guides_list.html. Protocol Offload To reduce the load on the control plane of the Cisco Nexus Series device, Cisco NX-OS allows you to offload link-level protocol processing to the Fabric Extender CPU. The following protocols are supported: • Link Layer Discovery Protocol (LLDP) •...
  • Page 294: Oversubscription

    Oversubscription Management Model The Cisco Nexus 2000 Series Fabric Extender is managed by its parent switch over the fabric interfaces through a zero-touch configuration model. The switch discovers the Fabric Extender by detecting the fabric interfaces of the Fabric Extender.
  • Page 295: Forwarding Model

    Connection Model Two methods (the static pinning fabric interface connection and the Port Channel fabric interface connection) allow the traffic from an end host to the parent switch to be distributed when going through the Cisco Nexus 2000 Series Fabric Extender.
  • Page 296: Static Pinning Fabric Interface Connection

    To guarantee a deterministic and sticky association across a reboot, you can manually redistribute the pinning. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 297: Port Channel Fabric Interface Connection

    If all links in the fabric port channel go down, all host interfaces on the FEX are set to the down state. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 298: Port Numbering Convention

    The Cisco Nexus 2000 Series Fabric Extender architecture allows hardware configurations with various host interface counts and speeds. Chassis The Cisco Nexus 2000 Series Fabric Extender is a 1 RU chassis that is designed for rack mounting. The chassis supports redundant hot-swappable fans and power supplies. Ethernet Interfaces There are four models of the Cisco Nexus 2000 Series Fabric Extender: •...
  • Page 299: Associating A Fabric Extender To A Fabric Interface

    Extender and switch. ◦ Support for a user configurable shared-buffer. • The Cisco Nexus B22 Fabric Extender for HP (NB22HP) has 16 1G/10-Gigabit Ethernet host interfaces. All host interfaces use all of the available fabric interfaces. • The Cisco Nexus B22 Fabric Extender for Fujitsu (NB22FTS) has 16 10-Gigabit Ethernet host interfaces.
  • Page 300: Associating A Fabric Extender To A Port Channel

    Eth101/1/7 Eth101/1/6 Eth101/1/5 Eth101/1/4 Eth101/1/3 Eth101/1/2 Eth101/1/1 Associating a Fabric Extender to a Port Channel Before You Begin Ensure that you have enabled the Fabric Extender feature. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 301 1/29 switch(config-if)# channel-group 4 switch(config-if)# no shutdown switch(config-if)# exit switch(config)# interface ethernet 1/30 switch(config-if)# channel-group 4 switch(config-if)# no shutdown switch(config-if)# exit switch(config)# interface ethernet 1/31 Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 302: Disassociating A Fabric Extender From An Interface

    Before You Begin Ensure that you have enabled the Fabric Extender feature. SUMMARY STEPS 1. configure terminal 2. interface {ethernet slot/port | port-channel channel} 3. no fex associate Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 303: Configuring Fabric Extender Global Features

    3. (Optional) description desc 4. (Optional) no description 5. (Optional) no type 6. (Optional) pinning max-links uplinks 7. (Optional) no pinning max-links 8. (Optional) serial serial 9. (Optional) no serial Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 304 ID to associate (using the fex associate Example: command) only if the Fabric Extender reports a matching serial number switch(config-fex)# serial JAF1339BDSK string. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 305: Enabling The Fabric Extender Locator Led

    You may want to perform this function in these two situations: • A change in the max-links configuration. • If you need to maintain the pinning order of host interfaces to fabric interfaces. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 306: Changing The Number Of Links

    Fabric Extender, enter the fex pinning redistribute command. Redistributing Host Interfaces This command disrupts all the host interface ports of the Fabric Extender. Caution Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 307: Verifying The Fabric Extender Configuration

    Displays the SFP+ transceiver and diagnostic optical [fex-fabric] monitoring (DOM) information for the Fabric Extender uplinks. Displays the status of the feature sets on the device. show feature-set Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 308 Po100 Po100 Eth100/1/35 Po100 Po100 Eth100/1/36 Po100 Po100 Eth100/1/37 Po100 Po100 Eth100/1/38 Po100 Po100 Eth100/1/39 Po100 Po100 Eth100/1/40 Down Po100 Po100 Eth100/1/41 Po100 Po100 Eth100/1/42 Po100 Po100 Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 309 SFP+ transceiver that is plugged into the uplink port on the Fabric Extender: switch# show interface ethernet 1/40 transceiver fex-fabric Ethernet1/40 sfp is present name is CISCO-MOLEX INC part number is 74752-9026 revision is A0 Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 310: Verifying The Chassis Management Information

    --- --- ----- ---------------------------------- ------------------ ----------- 100 1 Fabric Extender 48x1GE + 4x10G Mod N2K-C2248TP-1GE present FEX Mod Sw World-Wide-Name(s) (WWN) --- --- -------------- ------ ----------------------------------------------- 100 1 4.2(1)N1(1) 0.103 Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 311 Module Sensor MajorThresh MinorThres CurTemp Status (Celsius) (Celsius) (Celsius) ----------------------------------------------------------------- Outlet-1 Outlet-2 Inlet-1 Die-1 Fan Fex: 101: ------------------------------------------------------ Model Status ------------------------------------------------------ Chassis N2K-C2148-FAN PS-1 absent PS-2 NXK-PAC-400W Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 312 HW Changes Bits : 0x0 Card Index : 11016 MAC Addresses : 00-00-00-00-00-00 Number of MACs Number of EPLD Port Type-Num : 1-48;2-4 Sensor #1 : 60,50 Sensor #2 : 60,50 Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 313 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 314: Configuring The Cisco Nexus N2248Tp-E Fabric Extender

    Stackmib OID Configuring the Cisco Nexus N2248TP-E Fabric Extender The Cisco Nexus 2248TP-E Fabric Extender supports all of the CLI commands of the Cisco Nexus 2248TP Fabric Extender with additional commands to configure the following: • Shared buffer (FEX global level) •...
  • Page 315: Configuring The Shared Buffer

    Note The hardware N2248TP-E shared-buffer-size switch(config-fex)# hardware N2248TP-E command specifies the default shared buffer size of shared-buffer-size 25000 25392 KB. Example: switch# configure terminal switch(config)# fex 100 Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 316: Configuring The Queue-Limit At The Global Level

    • The default queue-limit for rx (ingress) is 1 MB. Note The hardware N2248TP-E queue-limit rx command specifies the default rx queue-limit. Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 317: Configuring The Queue-Limit At The Port Level

    83000 tx • The default queue-limit for rx (ingress) is 1 MB. Example: switch# configure terminal switch(config)# interface ethernet 100/1/1 switch(config-if)# hardware N2248TP-E queue-limit 83000 tx switch(config-if)# Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01...
  • Page 318: Configuring Uplink Distance

    Configuring Uplink Distance Configuring Uplink Distance The Cisco Nexus N2248TP-E FEX supports a pause no-drop class up to a distance of 3000 meters between the FEX and the switch. The default cable length between the FEX and the switch is 300 meters.
  • Page 319 271, 273 debounce timer changing max-links parameters channel mode debounce timer, configuring port channels Ethernet interfaces channel modes default settings port channels Flex Link chassis description Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01 IN-1...
  • Page 320 Port Channel queries fail-over load balancing IGMPv1 IGMPv3 terminology image management FEX trunk port information about pvlan Flex Links FEX-number interface information, displaying layer 2 Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) IN-2 OL-25842-01...
  • Page 321 Link Layer Discovery Protocol, See LLDP default settings LLDP guidelines and limitations load balancing interoperation with IGMP snooping port channels interoperation with vPC snooping configuring licensing local switching Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01 IN-3...
  • Page 322 11, 12 ethernet interfaces about root guard guidelines and limitations RSTP 166, 169, 173, 187 port profiles active topology PortFast BPDU filtering Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) IN-4 OL-25842-01...
  • Page 323 Blocking State VLANs 40, 44, 46, 47, 66 disabled state adding ports to forwarding state changing learning state configuring STP bridge ID extended range STP overview private Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) OL-25842-01 IN-5...
  • Page 324 115, 130 vPC peer switch topology 134, 136 guidelines and limitations hybrid moving port channels into configuring Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.1(3)N1(1) IN-6 OL-25842-01...

Table of Contents