IP Routing: BGP Configuration Guide, Cisco IOS Release 15M&T
BGP per Neighbor SoO Configuration
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BGP per Neighbor SoO Configuration

Contents

BGP per Neighbor SoO Configuration

The BGP per Neighbor SoO Configuration feature simplifies the configuration of the site-of-origin (SoO) value. In Cisco IOS Release 12.4(9)T, 12.2(33)SRA, 12.2(31)SB2, and previous releases, the SoO value is configured using an inbound route map that sets the SoO value during the update process. Per neighbor SoO configuration introduces two new commands that can be configured in submodes under router configuration mode to set the SoO value. In Cisco IOS Release 12.4(24)T, support was added for 4-byte autonomous system numbers in asdot format only.

Finding Feature Information

Your software release may not support all the features documented in this module. For the latest caveats and feature information, see Bug Search Tool and the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the feature information table at the end of this module.

Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/​go/​cfn. An account on Cisco.com is not required.

Prerequisites for BGP per Neighbor SoO Configuration

This feature assumes that a Border Gateway Protocol (BGP) network is configured and that Cisco Express Forwarding is enabled in your network.

Restrictions for BGP per Neighbor SoO Configuration

A BGP neighbor or peer policy template-based SoO configuration takes precedence over the SoO value configured in an inbound route map.

Information About Configuring BGP per Neighbor SoO

Site of Origin BGP Community Attribute

The site-of-origin (SoO) extended community is a BGP extended community attribute that is used to identify routes that have originated from a site so that the readvertisement of that prefix back to the source site can be prevented. The SoO extended community uniquely identifies the site from which a router has learned a route. BGP can use the SoO value associated with a route to prevent routing loops.

Route Distinguisher

A route distinguisher (RD) creates routing and forwarding tables and specifies the default route distinguisher for a VPN. The RD is added to the beginning of an IPv4 prefix to change it into a globally unique VPN-IPv4 prefix. An RD can be composed in one of two ways: with an autonomous system number and an arbitrary number or with an IP address and an arbitrary number.

You can enter an RD in either of these formats:

  • Enter a 16-bit autonomous system number, a colon, and a 32-bit number. For example:

45000:3

  • Enter a 32-bit IP address, a colon, and a 16-bit number. For example:

192.168.10.15:1

BGP per Neighbor Site of Origin Configuration

There are three ways to configure an SoO value for a BGP neighbor:

  • BGP peer policy template--A peer policy template is created, and an SoO value is configured as part of the peer policy. Under address family IPv4 VRF, a neighbor is identified and is configured to inherit the peer policy that contains the SoO value.

  • BGP neighbor command--Under address family IPv4 VRF, a neighbor is identified, and an SoO value is configured for the neighbor.

  • BGP peer group--Under address family IPv4 VRF, a BGP peer group is configured, an SoO value is configured for the peer group, a neighbor is identified, and the neighbor is configured as a member of the peer group.


Note


A BGP neighbor or peer policy template-based SoO configuration takes precedence over the SoO value configured in an inbound route map.


The configuration of SoO values for BGP neighbors is performed on a provider edge (PE) router, which is the VPN entry point. When SoO is enabled, the PE router forwards prefixes to the customer premises equipment (CPE) only when the SoO tag of the prefix does not match the SoO tag configured for the CPE.

For example, in the figure below, an SoO tag is set as 65000:1 for the customer site that includes routers CPE1 and CPE2 with an autonomous system number of 65000. When CPE1 sends prefixes to PE1, PE1 tags the prefixes with 65000:1, which is the SoO tag for CPE1 and CPE2. When PE1 sends the tagged prefixes to PE2, PE2 performs a match against the SoO tag from CPE2. Any prefixes with the tag value of 65000:1 are not sent to CPE2 because the SoO tag matches the SoO tag of CPE2, and a routing loop is avoided.

Figure 1. Network Diagram for SoO Example

Benefits of BGP per Neighbor Site of Origin

In releases prior to the introduction of this feature, the SoO extended community attribute is configured using an inbound route map that sets the SoO value during the update process. With the introduction of the BGP per Neighbor Site of Origin feature, two new commands configured in submodes under router configuration mode simplify the SoO value configuration.

How to Configure BGP per Neighbor SoO

Enabling Cisco Express Forwarding and Configuring VRF Instances

Perform this task on both of the PE routers in the figure above to configure Virtual Routing and Forwarding (VRF) instances to be used with the per-VRF assignment tasks. In this task, Cisco Express Forwarding is enabled, and a VRF instance named SOO_VRF is created. To make the VRF functional, a route distinguisher is created, and the VRF is associated with an interface. When the route distinguisher is created, the routing and forwarding tables are created for the VRF instance named SOO_VRF. After associating the VRF with an interface, the interface is configured with an IP address.

SUMMARY STEPS

    1.    enable

    2.    configure terminal

    3.    ip cef

    4.    ip vrf vrf-name

    5.    rd route-distinguisher

    6.    route-target {export | both} route-target-ext-community

    7.    route-target {import | both} route-target-ext-community

    8.    exit

    9.    interface type number

    10.    ip vrf forwarding vrf-name [downstream vrf-name2]

    11.    ip address ip-address mask [secondary]

    12.    end

    13.    show ip vrf [brief | detail | interfaces | id] [vrf-name] [output-modifiers]


DETAILED STEPS
     Command or ActionPurpose
    Step 1 enable


    Example:
    Device> enable
     

    Enables privileged EXEC mode.

    • Enter your password if prompted.

     
    Step 2 configure terminal


    Example:
    Device# configure terminal
     

    Enters global configuration mode.

     
    Step 3 ip cef


    Example:
    Device(config)# ip cef
     

    Enables Cisco Express Forwarding on the route processor.

     
    Step 4 ip vrf vrf-name


    Example:
    Device(config)# ip vrf SOO_VRF
     

    Defines a VRF instance and enters VRF configuration mode.

     
    Step 5 rd route-distinguisher


    Example:
    Device(config-vrf)# rd 1:1
     

    Creates routing and forwarding tables for a VRF and specifies the default RD for a VPN.

    • Use the route-distinguisher argument to specify the default RD for a VPN. There are two formats that you can use to specify an RD:
      • A 16-bit autonomous system number, a colon, and a 32-bit number, for example: 65000:3
      • A 32-bit IP address, a colon, and a 16-bit number, for example: 192.168.1.2:51
    • In this example, the RD uses an autonomous system number with the number 1 after the colon.

     
    Step 6 route-target {export | both} route-target-ext-community


    Example:
    Device(config-vrf)# route-target export 1:1
     

    Creates a route-target extended community for a VRF.

    • Use the export keyword to export routing information to the target VPN extended community.

    • Use the both keyword to both import routing information from, and export routing information to, the target VPN extended community.

    • Use the route-target-ext-community argument to specify the VPN extended community.

    Note   

    Only the syntax applicable to this step is displayed. For a different use of this syntax, see Step 7.

     
    Step 7 route-target {import | both} route-target-ext-community


    Example:
    Device(config-vrf)# route-target import 1:1
     

    Creates a route-target extended community for a VRF.

    • Use the import keyword to import routing information from the target VPN extended community.

    • Use the both keyword to both import routing information from, and export routing information to, the target VPN extended community.

    • Use the route-target-ext-community argument to specify the VPN extended community.

     
    Step 8 exit


    Example:
    Device(config-vrf)# exit
     

    Exits VRF configuration mode and returns to global configuration mode.

     
    Step 9 interface type number


    Example:
    Device(config)# interface GigabitEthernet 1/0/0
     

    Configures an interface type and enters interface configuration mode.

     
    Step 10 ip vrf forwarding vrf-name [downstream vrf-name2]


    Example:
    Device(config-if)# ip vrf forwarding SOO_VRF
     

    Associates a VRF with an interface or subinterface.

    • In this example, the VRF named SOO_VRF is associated with Gigabit Ethernet interface 1/0/0.

    Note   

    Executing this command on an interface removes the IP address, so the IP address should be reconfigured.

     
    Step 11 ip address ip-address mask [secondary]


    Example:
    Device(config-if)# ip address 192.168.1.2 255.255.255.0
     

    Configures an IP address.

    • In this example, Gigabit Ethernet interface 1/0/0 is configured with an IP address of 192.168.1.2.

     
    Step 12 end


    Example:
    Device(config-if)# end
     

    Exits interface configuration mode and returns to privileged EXEC mode.

     
    Step 13 show ip vrf [brief | detail | interfaces | id] [vrf-name] [output-modifiers]


    Example:
    Device# show ip vrf
     

    Displays the configured VRFs.

    • Use this command to verify the configuration of this task.

     

    Examples

    The following output of the show ip vrf command displays the VRF named SOO_VRF configured in this task.

    Device# show ip vrf
    
    Name                             Default RD            Interfaces
    SOO_VRF                                 1:1                GE1/0/0

    Configuring a per Neighbor SoO Value Using a BGP Peer Policy Template

    Perform this task on router PE1 in the figure above to configure an SoO value for a BGP neighbor at the router CPE1 in the figure above using a peer policy template. In this task, a peer policy template is created, and the SoO value is configured for the peer policy. Under address family IPv4 VRF, a neighbor is identified and is configured to inherit the peer policy that contains the SoO value.

    For a configuration example involving 4-byte autonomous system numbers, see the “Example: Configuring a per Neighbor SoO Value with a 4-Byte AS Number Using a BGP Peer Policy Template” section.


    Note


    If a BGP peer inherits from several peer policy templates that specify different SoO values, the SoO value in the last template applied takes precedence and is applied to the peer. However, direct configuration of the SoO value on the BGP neighbor overrides any inherited template configurations of the SoO value.


    BGP Peer Policy Templates

    Peer policy templates are used to configure BGP policy commands that are configured for neighbors that belong to specific address families. Peer policy templates are configured once and then applied to many neighbors through the direct application of a peer policy template or through inheritance from peer policy templates. The configuration of peer policy templates simplifies the configuration of BGP policy commands that are applied to all neighbors within an autonomous system.

    Peer policy templates support inheritance. A directly applied peer policy template can directly or indirectly inherit configurations from up to seven peer policy templates. So, a total of eight peer policy templates can be applied to a neighbor or neighbor group.

    The configuration of peer policy templates simplifies and improves the flexibility of BGP configuration. A specific policy can be configured once and referenced many times. Because a peer policy supports up to eight levels of inheritance, very specific and very complex BGP policies can be created.

    For more details about BGP peer policy templates, see the "Configuring a Basic BGP Network" module.

    Before You Begin

    This task assumes that the task described in the "Verifying CEF and Configuring VRF Instances" section has been performed.


    Note


    A BGP peer cannot inherit from a peer policy or session template and be configured as a peer group member at the same. BGP templates and BGP peer groups are mutually exclusive.


    SUMMARY STEPS

      1.    enable

      2.    configure terminal

      3.    router bgp autonomous-system-number

      4.    template peer-policy policy-template-name

      5.    soo extended-community-value

      6.    exit-peer-policy

      7.    address-family ipv4 [unicast | multicast| vrf vrf-name]

      8.    neighbor ip-address remote-as autonomous-system-number

      9.    neighbor ip-address activate

      10.    neighbor ip-address inherit peer-policy policy-template-name

      11.    end


    DETAILED STEPS
       Command or ActionPurpose
      Step 1 enable


      Example:
      Router> enable
       

      Enables privileged EXEC mode.

      • Enter your password if prompted.

       
      Step 2 configure terminal


      Example:
      Router# configure terminal
       

      Enters global configuration mode.

       
      Step 3 router bgp autonomous-system-number


      Example:
      Router(config)# router bgp 50000
       

      Enters router configuration mode for the specified routing process.

       
      Step 4 template peer-policy policy-template-name


      Example:
      Router(config-router)# template peer-policy SOO_POLICY
       

      Creates a peer policy template and enters policy-template configuration mode.

       
      Step 5 soo extended-community-value


      Example:
      Router(config-router-ptmp)# soo 65000:1
       

      Sets the SoO value for a BGP peer policy template.

      • Use the extended-community-value argument to specify the VPN extended community value. The value takes one of the following formats:
        • A 16-bit autonomous system number, a colon, and a 32-bit number, for example: 45000:3
        • A 32-bit IP address, a colon, and a 16-bit number, for example: 192.168.10.2:51
      • In this example, the SoO value is set at 65000:1.

       
      Step 6 exit-peer-policy


      Example:
      Router(config-router-pmtp)# exit-peer-policy
       

      Exits policy-template configuration mode and returns to router configuration mode.

       
      Step 7 address-family ipv4 [unicast | multicast| vrf vrf-name]


      Example:
      Router(config-router)# address-family ipv4 vrf SOO_VRF
       

      Specifies the IPv4 address family and enters address family configuration mode.

      • Use the unicast keyword to specify the IPv4 unicast address family. By default, the router is placed in configuration mode for the IPv4 unicast address family if the unicast keyword is not specified with the address-family ipv4 command.

      • Use the multicast keyword to specify IPv4 multicast address prefixes.

      • Use the vrf keyword and vrf-name argument to specify the name of the VRF instance to associate with subsequent IPv4 address family configuration mode commands.

       
      Step 8 neighbor ip-address remote-as autonomous-system-number


      Example:
      Router(config-router-af)# neighbor 192.168.1.1 remote-as 65000
       

      Adds the IP address of the neighbor in the specified autonomous system to the IPv4 multiprotocol BGP neighbor table of the local router.

       
      Step 9 neighbor ip-address activate


      Example:
      Router(config-router-af)# neighbor 192.168.1.1 activate
       

      Enables the neighbor to exchange prefixes for the IPv4 VRF address family with the local router.

       
      Step 10 neighbor ip-address inherit peer-policy policy-template-name


      Example:
      Router(config-router-af)# neighbor 192.168.1.1 inherit peer-policy SOO_POLICY
       

      Sends a peer policy template to a neighbor so that the neighbor can inherit the configuration.

      • In this example, the router is configured to send the peer policy template named SOO_POLICY to the 192.168.1.1 neighbor to inherit. If another peer policy template is indirectly inherited from SOO_POLICY, the indirectly inherited configuration will also be applied. Up to seven additional peer policy templates can be indirectly inherited from SOO_POLICY.

       
      Step 11 end


      Example:
      Router(config-router-af)# end
       

      Exits address family configuration mode and returns to privileged EXEC mode.

       

      Configuring a per Neighbor SoO Value Using a BGP neighbor Command

      Perform this task on router PE2 in the figure above to configure an SoO value for the BGP neighbor at router CPE2 in the figure above using a neighbor command. For the IPv4 VRF address family, a neighbor is identified, and an SoO value is configured for the neighbor.

      Direct configuration of the SoO value on a BGP neighbor overrides any inherited peer policy template configurations of the SoO value.

      Before You Begin

      This task assumes that the task described in the “Verifying CEF and Configuring VRF Instances” section has been performed with appropriate changes to interfaces and IP addresses.

      SUMMARY STEPS

        1.    enable

        2.    configure terminal

        3.    router bgp autonomous-system-number

        4.    address-family ipv4 [unicast | multicast | vrf vrf-name]

        5.    neighbor {ip-address | peer-group-name} remote-as autonomous-system-number

        6.    neighbor ip-address activate

        7.    neighbor {ip-address | peer-group-name} soo extended-community-value

        8.    end


      DETAILED STEPS
         Command or ActionPurpose
        Step 1 enable


        Example:
        Device> enable
         

        Enables privileged EXEC mode.

        • Enter your password if prompted.

         
        Step 2 configure terminal


        Example:
        Device# configure terminal
         

        Enters global configuration mode.

         
        Step 3 router bgp autonomous-system-number


        Example:
        Device(config)# router bgp 50000
         

        Enters router configuration mode for the specified routing process.

         
        Step 4 address-family ipv4 [unicast | multicast | vrf vrf-name]


        Example:
        Device(config-router)# address-family ipv4 vrf SOO_VRF
         

        Specifies the IPv4 address family and enters address family configuration mode.

        • Use the unicast keyword to specify the IPv4 unicast address family. By default, the router is placed in configuration mode for the IPv4 unicast address family if the unicast keyword is not specified with the address-family ipv4 command.

        • Use the multicast keyword to specify IPv4 multicast address prefixes.

        • Use the vrf keyword and vrf-name argument to specify the name of the VRF instance to associate with subsequent IPv4 address family configuration mode commands.

         
        Step 5 neighbor {ip-address | peer-group-name} remote-as autonomous-system-number


        Example:
        Device(config-router-af)# neighbor 192.168.2.1 remote-as 65000
         

        Adds the IP address of the neighbor in the specified autonomous system to the IPv4 multiprotocol BGP neighbor table of the local router.

         
        Step 6 neighbor ip-address activate


        Example:
        Device(config-router-af)# neighbor 192.168.2.1 activate
         

        Enables the neighbor to exchange prefixes for the IPv4 VRF address family with the local router.

        • In this example, the external BGP peer at 192.168.2.1 is activated.

        Note   

        If a peer group has been configured in Step 5 , do not use this step because BGP peer groups are activated when any parameter is configured. For example, a BGP peer group is activated when an SoO value is configured using the neighbor soo command in Step 7.

         
        Step 7 neighbor {ip-address | peer-group-name} soo extended-community-value


        Example:
        Device(config-router-af)# neighbor 192.168.2.1 soo 65000:1
         

        Sets the site-of-origin (SoO) value for a BGP neighbor or peer group.

        • In this example, the neighbor at 192.168.2.1 is configured with an SoO value of 65000:1.

         
        Step 8 end


        Example:
        Device(config-router-af)# end
         

        Exits address family configuration mode and returns to privileged EXEC mode.

         

        Configuring a per Neighbor SoO Value Using a BGP Peer Group

        Perform this task on router PE1 in the figure above to configure an SoO value for the BGP neighbor at router CPE1 in the figure above using a neighbor command with a BGP peer group. Under address family IPv4 VRF, a BGP peer group is created and an SoO value is configured using a BGP neighbor command, and a neighbor is then identified and added as a peer group member. A BGP peer group member inherits the configuration associated with a peer group, which in this example, includes the SoO value.

        Direct configuration of the SoO value on a BGP neighbor overrides any inherited peer group configurations of the SoO value.

        Before You Begin

        This task assumes that the task described in “Enabling Cisco Express Forwarding and Configuring VRF Instances” has been performed.


        Note


        A BGP peer cannot inherit from a peer policy or session template and be configured as a peer group member at the same. BGP templates and BGP peer groups are mutually exclusive.


        SUMMARY STEPS

          1.    enable

          2.    configure terminal

          3.    router bgp autonomous-system-number

          4.    address-family ipv4 [unicast | multicast | vrf vrf-name]

          5.    neighbor peer-group-name peer-group

          6.    neighbor {ip-address | peer-group-name} soo extended-community-value

          7.    neighbor ip-address remote-as autonomous-system-number

          8.    neighbor ip-address activate

          9.    neighbor ip-address peer-group peer-group-name

          10.    end


        DETAILED STEPS
           Command or ActionPurpose
          Step 1 enable


          Example:
          Device> enable
           

          Enables privileged EXEC mode.

          • Enter your password if prompted.

           
          Step 2 configure terminal


          Example:
          Device# configure terminal
           

          Enters global configuration mode.

           
          Step 3 router bgp autonomous-system-number


          Example:
          Device(config)# router bgp 50000
           

          Enters router configuration mode for the specified routing process.

           
          Step 4 address-family ipv4 [unicast | multicast | vrf vrf-name]


          Example:
          Device(config-router)# address-family ipv4 vrf SOO_VRF
           

          Specifies the IPv4 address family and enters address family configuration mode.

          • Use the unicast keyword to specify the IPv4 unicast address family. By default, the router is placed in configuration mode for the IPv4 unicast address family if the unicast keyword is not specified with the address-family ipv4 command.

          • Use the multicast keyword to specify IPv4 multicast address prefixes.

          • Use the vrf keyword and vrf-name argument to specify the name of the VRF instance to associate with subsequent IPv4 address family configuration mode commands.

           
          Step 5 neighbor peer-group-name peer-group


          Example:
          Device(config-router-af)# neighbor SOO_group peer-group
           

          Creates a BGP peer group.

           
          Step 6 neighbor {ip-address | peer-group-name} soo extended-community-value


          Example:
          Device(config-router-af)# neighbor SOO_group soo 65000:1
           

          Sets the site-of-origin (SoO) value for a BGP neighbor or peer group.

          • In this example, the BGP peer group, SOO_group, is configured with an SoO value of 65000:1.

           
          Step 7 neighbor ip-address remote-as autonomous-system-number


          Example:
          Device(config-router-af)# neighbor 192.168.1.1 remote-as 65000
           

          Adds the IP address of the neighbor in the specified autonomous system to the IPv4 multiprotocol BGP neighbor table of the local router.

           
          Step 8 neighbor ip-address activate


          Example:
          Device(config-router-af)# neighbor 192.168.1.1 activate
           

          Enables the neighbor to exchange prefixes for the IPv4 VRF address family with the local router.

           
          Step 9 neighbor ip-address peer-group peer-group-name


          Example:
          Device(config-router-af)# neighbor 192.168.1.1 peer-group SOO_group
           

          Assigns the IP address of a BGP neighbor to a peer group.

           
          Step 10 end


          Example:
          Device(config-router-af)# end
           

          Exits address family configuration mode and returns to privileged EXEC mode.

           

          Configuration Examples for BGP per Neighbor SoO Configuration

          Example: Configuring a per Neighbor SoO Value Using a BGP Peer Policy Template

          The following example shows how to create a peer policy template and configure an SoO value as part of the peer policy. After enabling Cisco Express Forwarding and configuring a VRF instance named SOO_VRF, a peer policy template is created and an SoO value is configured as part of the peer policy. Under the IPv4 VRF address family, a neighbor is identified and configured to inherit the peer policy that contains the SoO value.

          ip cef
          ip vrf SOO_VRF
           rd 1:1
           route-target export 1:1
           route-target import 1:1
           exit
          interface GigabitEthernet 1/0/0
           ip vrf forwarding SOO_VRF
           ip address 192.168.1.2 255.255.255.0
           exit
          router bgp 50000
           template peer-policy SOO_POLICY
            soo 65000:1
            exit-peer-policy
           address-family ipv4 vrf SOO_VRF
            neighbor 192.168.1.1 remote-as 65000
            neighbor 192.168.1.1 activate
            neighbor 192.168.1.1 inherit peer-policy SOO_POLICY
            end

          Example: Configuring a per Neighbor SoO Value with a 4-Byte AS Number Using a BGP Peer Policy Template

          The following example shows how to create a peer policy template and configure an SoO value using a 4-byte autonomous system number, 1.2 in asdot format, as part of the peer policy. Under the IPv4 VRF address family, a neighbor is identified and configured to inherit the peer policy that contains the SoO value.

          router bgp 1.2
           template peer-policy SOO_POLICY
            soo 1.2:3
            exit-peer-policy
           address-family ipv4 vrf SOO_VRF
            neighbor 192.168.3.2 remote-as 1.14
            neighbor 192.168.3.2 activate
            neighbor 192.168.3.2 inherit peer-policy SOO_POLICY
            end
          

          The following example shows how to create a peer policy template and configure an SoO value using a 4-byte autonomous system number, 65538 in asplain format, as part of the peer policy. Under the IPv4 VRF address family, a neighbor is identified and configured to inherit the peer policy that contains the SoO value.

          router bgp 65538
           template peer-policy SOO_POLICY
            soo 65538:3
            exit-peer-policy
           address-family ipv4 vrf SOO_VRF
            neighbor 192.168.3.2 remote-as 65550
            neighbor 192.168.3.2 activate
            neighbor 192.168.3.2 inherit peer-policy SOO_POLICY
            end

          Example: Configuring a per Neighbor SoO Value Using a BGP neighbor Command

          The following example shows how to configure an SoO value for a BGP neighbor. After enabling Cisco Express Forwarding and configuring a VRF instance named SOO_VRF, a neighbor is identified in the IPv4 VRF address family and an SoO value is configured for the neighbor.

          ip cef
          ip vrf SOO_VRF
           rd 1:1
           route-target export 1:1
           route-target import 1:1
           exit
          interface GigabitEthernet 1/0/0
           ip vrf forwarding SOO_VRF
           ip address 192.168.2.2 255.255.255.0
           exit
          router bgp 50000
           address-family ipv4 vrf SOO_VRF
            neighbor 192.168.2.1 remote-as 65000
            neighbor 192.168.2.1 activate
            neighbor 192.168.2.1 soo 65000:1
            end

          Example: Configuring a per Neighbor SoO Value Using a BGP neighbor Command and 4-Byte Autonomous System Numbers

          The following example shows how to configure an SoO value for a BGP neighbor. In this example, all BGP neighbors, route targets, and SoO values use 4-byte autonomous system numbers in asplain format. After checking that CEF is enabled, a VRF instance named SOO_VRF is configured with route targets. In a BGP router session, a neighbor is configured in the IPv4 VRF address family, and an SoO value is configured for the neighbor.

          show ip cef
          ip vrf SOO_VRF
           rd 100:200
           route-target export 1.14:1
           route-target import 1.14:1
           exit
          interface Ethernet 1/0
           ip vrf forwarding SOO_VRF
           ip address 192.168.2.2 255.255.255.0
           exit
          router bgp 1.2
           address-family ipv4 vrf SOO_VRF
            neighbor 192.168.2.1 remote-as 1.14
            neighbor 192.168.2.1 activate
            neighbor 192.168.2.1 soo 1.14:1
            end

          Example: Configuring a per Neighbor SoO Value Using a BGP Peer Group

          The following example shows how to configure an SoO value for a BGP peer group. After enabling Cisco Express Forwarding and configuring a VRF instance named SOO_VRF, a BGP peer group is configured in the IPv4 VRF address family, an SoO value is configured for the peer group, a neighbor is identified, and the neighbor is configured as a member of the peer group.

          ip cef
          ip vrf SOO_VRF
           rd 1:1
           route-target export 1:1
           route-target import 1:1
           exit
          interface GigabitEthernet 1/0/0
           ip vrf forwarding SOO_VRF
           ip address 192.168.1.2 255.255.255.0
           exit
          router bgp 50000
           address-family ipv4 vrf SOO_VRF
            neighbor SOO_GROUP peer-group
            neighbor SOO_GROUP soo 65000:65
            neighbor 192.168.1.1 remote-as 65000
            neighbor 192.168.1.1 activate
            neighbor 192.168.1.1 peer-group SOO_GROUP 
            end

          Additional References

          Related Documents

          Related Topic

          Document Title

          Cisco IOS commands

          Cisco IOS Master Command List, All Releases

          BGP commands

          Cisco IOS IP Routing: BGP Command Reference

          IP Switching commands

          Cisco IOS IP Switching Command Reference

          MIBs

          MIB

          MIBs Link

          To locate and download MIBs for selected platforms, Cisco IOS releases, and feature sets, use Cisco MIB Locator found at the following URL:

          http:/​/​www.cisco.com/​go/​mibs

          Technical Assistance

          Description

          Link

          The Cisco Support and Documentation website provides online resources to download documentation, software, and tools. Use these resources to install and configure the software and to troubleshoot and resolve technical issues with Cisco products and technologies. Access to most tools on the Cisco Support and Documentation website requires a Cisco.com user ID and password.

          http:/​/​www.cisco.com/​cisco/​web/​support/​index.html

          Feature Information for BGP per Neighbor SoO Configuration

          The following table provides release information about the feature or features described in this module. This table lists only the software release that introduced support for a given feature in a given software release train. Unless noted otherwise, subsequent releases of that software release train also support that feature.

          Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/​go/​cfn. An account on Cisco.com is not required.

          Table 1 Feature Information for BGP per Neighbor SoO Configuration

          Feature Name

          Releases

          Feature Information

          BGP per Neighbor SoO Configuration

          12.2(33)SB

          12.2(33)SRB

          12.4(11)T

          15.0(1)SY

          The BGP per neighbor SOO configuration feature simplifies the configuration of the site-of-origin (SoO) parameter. In earlier releases, the SoO parameter is configured using an inbound route map that sets the SoO value during the update process. The per neighbor SoO configuration introduces two new commands that can be configured in submodes under router configuration mode to set the SoO value.

          The following commands were introduced by this feature: neighbor soo, and soo.