Cisco Nexus 1000V Layer 2 Switching Configuration Guide, Release 4.2(1)SV2(1.1)
Supporting Redundant Routing Protocols
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Supporting Redundant Routing Protocols

This chapter contains the following sections:

Information About Redundant Routing Protocols

Cisco Nexus 1000V implements a loop detection mechanism based on source and destination MAC address and will drop packets coming in on uplink ports if the source MAC is already present on a local vEthernet interface. As a result, the protocols such as Virtual Router Redundancy Protocol (VRRP), Common Address Redundancy Protocol (CARP), Hot Standby Router Protocol (HSRP), and other similar protocols would fail on virtual machines associated to Cisco Nexus 1000V.

Disabling loop detection provides a flexible way of supporting these protocols on virtual machines associated to Cisco Nexus 1000V. By disabling the loop detection mechanism, you can configure any combination of the above mentioned protocols on a port profile or a vEthernet interface. As a result you can run multiple protocols on the same virtual machine.

Guidelines and Limitations

Supporting the redundant routing protocols feature has the following guidelines and limitations:

  • Disable IGMP Snooping on both Cisco Nexus 1000V and upstream switches between the servers to support most redundant routing protocols. See Enabling or Disabling IGMP Snooping Globally for the VSM.
  • Disable loop detection configuration is not supported on PVLAN ports.
  • Disable loop detection configuration is not supported on the port security ports.

Supporting Redundant Routing Protocols

Configuring a vEthernet Interface to Support Redundant Routing Protocols

Use this procedure to configure a vEthernet interface to support redundant routing protocols.

Before You Begin
  • You are logged in to the CLI in EXEC mode.
  • You know which redundant routing protocol you want to disable.
Procedure
     Command or ActionPurpose
    Step 1switch# configure terminal 

    Enters global configuration mode.

     
    Step 2switch(config)# interface vethernet interface-number 

    Enters the interface configuration mode for the specified vEthernet interface (from 1 to 1048575).

     
    Step 3switch(config-if)# disable-loop-detection { carp | hsrp | vrrp |custom-rp [src-mac-range s_mac end_mac] [dest-ip ip_address] [ip-proto no] [port port]} 

    Enables or disables the loop detection mechanism to support a redundant routing protocol on vEthernet interface.

    • disable-loop-detection: Disables the loop detection mechanism.
    • no disable-loop-detection: Enables the loop detection mechanism. This is the default configuration.
    The protocols supported on a vEthernet interface include:
    • carp - Common Address Redundancy Protocol
    • custom-rp - User defined protocol
    • hsrp - Hot Standby Router Protocol
    • vrrp - Virtual Router Redundancy Protocol
    The parameters for custom defined protocols include:
    • src-mac-range - Source MAC address range for the user defined protocol.
    • dest-ip - Destination IP address for the user defined protocol.
    • ip-proto - IP protocol number for the user defined protocol.
    • port - UDP or TCP destination port number for the user defined protocol.
     
    Step 4switch(config-if)# show running-config interface vethernet interface-number  (Optional)

    Displays the interface status and information.

     
    Step 5switch(config-if)# copy running-config startup-config  (Optional)

    Saves the change persistently through reboots and restarts by copying the running configuration to the startup configuration.

     

    The following example shows how to configure a vEthernet interface to support VRRP, CERP, HSRP, and user defined protocols on a virtual machine:

    switch# configure terminal
switch(config)# int veth5
switch(config-if)# disable-loop-detection carp
switch(config-if)# disable-loop-detection vrrp
switch(config-if)# disable-loop-detection hsrp
switch(config-if)# disable-loop-detection custom-rp dest-ip 224.0.0.12 port 2234
switch(config-if)# end
switch# show running-config interface vethernet 5
!Command: show running-config interface Vethernet5
!Time: Fri Nov 4 02:21:24 2011

version 4.2(1)SV1(5.1)

interface Vethernet5
inherit port-profile vm59
description Fedora117, Network Adapter 2
disable-loop-detection carp
disable-loop-detection custom-rp dest-ip 224.0.0.12 port 2234
disable-loop-detection hsrp
disable-loop-detection vrrp
vmware dvport 32 dvswitch uuid "ea 5c 3b 50 cd 00 9f 55-41 a3 2d 61 84 9e 0e c4"
vmware vm mac 0050.56B3.00B2

switch#

    Configuring a Port Profile to Support Redundant Routing Protocols

    Use this procedure to configure a port profile to support redundant routing protocols. Use this procedure when the master in a master/slave relationship has lost connectivity, the slave has taken over the master role, and the original master is attempting to overtake the master role.


    Note

    If you configure a vEthernet Interface and a port profile to run multiple protocols on the same virtual machine, then the configuration on the vEthernet Interface overrides the configuration on the port profile.

    Before You Begin
    • You are logged in to the CLI in EXEC mode.
    • You know which redundant routing protocol you want to disable.
    Procedure
       Command or ActionPurpose
      Step 1switch# configure terminal 

      Enters global configuration mode.

       
      Step 2switch(config)# port-profile name 

      Enters port profile configuration mode for the named port profile.

       
      Step 3switch(config-port-prof)# switchport mode {access | trunk} 

      Designates that the interface is to be used as a trunking port.

      A trunk port transmits untagged packets for the native VLAN and transmits encapsulated, tagged packets for all other VLANs.

       
      Step 4switch(config-port-prof)# no shutdown 

      Administratively enables all ports in the profile.

       
      Step 5switch(config-port-prof)# disable-loop-detection { carp | hsrp | vrrp |custom-rp [ src-mac-range s_mac end_mac ] [ dest-ip ip_address ] [ ip-proto no ] [ port port ]} 

      Enables or disables the loop detection mechanism to support a redundant routing protocol on vEthernet interface.

      • disable-loop-detection: Disables the loop detection mechanism.
      • no disable-loop-detection: Enables the loop detection mechanism. This is the default configuration.
      The protocols supported on a vEthernet interface include:
      • carp - Common Address Redundancy Protocol
      • custom-rp - User defined protocol
      • hsrp - Hot Standby Router Protocol
      • vrrp - Virtual Router Redundancy Protocol
      The parameters for custom defined protocols include:
      • src-mac-range - Source MAC address range for the user defined protocol.
      • dest-ip - Destination IP address for the user defined protocol.
      • ip-proto - IP protocol number for the user defined protocol.
      • port - UDP or TCP destination port number for the user defined protocol.
       
      Step 6switch(config-port-prof)# show port-profile [ brief | expand-interface | usage ] [ name profile-name ]  (Optional)

      Displays the configuration for verification.

       
      Step 7switch(config-port-prof)# copy running-config startup-config  (Optional)

      Saves the change persistently through reboots and restarts by copying the running configuration to the startup configuration.

       

      This example shows how to disable loop detection for the Hot Standby Router Protocol:

      switch# configure terminal
switch(config)# port-profile hsrp-1
switch(config-port-prof)# switchport mode trunk
switch(config-port-prof)# no shutdown
switch(config-port-prof)# disable-loop-detection hsrp
switch(config-port-prof)# state enabled
switch(config-port-prof)# vmware port-group
switch(config-port-prof)# show port-profile name hsrp-1
port-profile hsrp-1
 type: Vethernet
 description:
 status: enabled
 max-ports: 32
 min-ports: 1
 inherit:
 config attributes:
  switchport mode trunk
  disable-loop-detection hsrp
  no shutdown
 evaluated config attributes:
  switchport mode trunk
  disable-loop-detection hsrp
  no shutdown
 assigned interfaces:
 port-group: hsrp-1
 system vlans: none
 capability l3control: no
 capability iscsi-multipath: no
 capability vxlan: no
 capability l3-vservice: no
 port-profile role: none
 port-binding: static

      This example shows how to disable loop detection for the Virtual Router Redundancy Protocol:

      n1000v# configure terminal
switch(config)# port-profile vrrp-1
switch(config-port-prof)# switchport mode trunk
switch(config-port-prof)# no shutdown
switch(config-port-prof)# disable-loop-detection vrrp
switch(config-port-prof)# state enabled
switch(config-port-prof)# vmware port-group
switch(config-port-prof)# show port-profile name vrrp-1
port-profile vrrp-1
 type: Vethernet
 description:
 status: enabled
 max-ports: 32
 min-ports: 1
 inherit:
 config attributes:
  switchport mode trunk
  disable-loop-detection vrrp
  no shutdown
 evaluated config attributes:
  switchport mode trunk
  disable-loop-detection vrrp
  no shutdown
 assigned interfaces:
 port-group: vrrp-1
 system vlans: none
 capability l3control: no
 capability iscsi-multipath: no
 capability vxlan: no
 capability l3-vservice: no
 port-profile role: none
 port-binding: static

      Feature History for Supporting Redundant Routing Protocol

      Feature Name

      Feature Name

      Releases

      Supporting Redundant Routing Protocol

      4.2(1)SV1(5.1)

      This feature was introduced