DHCPv6 Relay and Server - MPLS VPN Support

The Dynamic Host Configuration Protocol for IPv6 (DHCPv6) relay implementation allows the configuration of the destination virtual private network (VPN) routing and forwarding (VRF) instance to which the relay messages will be forwarded. The DHCPv6 server implementation of MPLS VPN support allows a per-pool configuration so DHCPv6 pools can be associated with a VRF instance.

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.

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.

Information About DHCPv6 Relay and Server - MPLS VPN Support

DHCPv6 Server and Relay—MPLS VPN Support

To facilitate managed central services in a Multiprotocol Label Switching (MPLS)-based network, DHCPv6 must be made MPLS-aware so that a single resource can be used to serve multiple VPNs instead of dedicating a resource to a single VPN.

The DHCPv6 server implementation of MPLS VPN allows a per-pool configuration so that DHCPv6 pools can be associated with a VPN routing and forwarding (VRF) instance. The DHCPv6 server differentiates clients from various VRFs and assigns an IPv6 prefix accordingly from the respective VRF pools. Meanwhile, the DHCPv6 bindings store the clients’ VRF information.

The DHCPv6 relay implementation allows the configuration of the destination VRF instance to which the relay messages will be forwarded. The relay adds the client’s VPN information while forwarding the client’s DHCPv6 requests toward the server, and the relay agent then processes the client’s VPN information in reply packets from the server.

The relay agent adds IPv6 static routes for delegated prefixes in corresponding clients’ VRF, and the relay agent’s high availability (HA) functionality synchronizes the VRF information while synchronizing static routes created by the relay process.

The DHCPv6 relay and server VRF-aware features are disabled by default.

How to Configure DHCPv6 Relay and Server - MPLS VPN Support

Configuring a VRF-Aware Relay and Server for MPLS VPN Support

Configuring a VRF-Aware Relay


Note

You do not have to configure this feature on specified interfaces. If you want the feature to be enabled globally only on a device, perform steps 1, 2, and 3

SUMMARY STEPS

    1.    enable

    2.    configure terminal

    3.    ipv6 dhcp-relay option vpn

    4.    interface type number

    5.    ipv6 dhcp relay option vpn

    6.    ipv6 dhcp relay destination ipv6-address [interface-type interface-number | vrf vrf-name | global]

    7.    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 ipv6 dhcp-relay option vpn


    Example:
    Device(config)# ipv6 dhcp-relay option vpn
     

    Enables the DHCP for IPv6 relay VRF-aware feature globally.

     
    Step 4 interface type number


    Example:
    Device(config)# interface gigabitethernet 0/0/0
     

    Specifies an interface type and number, and enters interface configuration mode.

     
    Step 5 ipv6 dhcp relay option vpn


    Example:
    Device(config-if)# ipv6 dhcp relay option vpn
     

    Enables the DHCP for IPv6 relay VRF-aware feature on the specified interface. Enabling this command supersedes the configuration that is enabled by using the ipv6 dhcp-relay option vpn command.

     
    Step 6 ipv6 dhcp relay destination ipv6-address [interface-type interface-number | vrf vrf-name | global]


    Example:
    Device(config-if)# ipv6 dhcp relay destination FE80::250:A2FF:FEBF:A056 ethernet 0/0
     

    Specifies a destination address to which client messages are forwarded.

     
    Step 7 end


    Example:
    Device(config-if)# end
     

    Returns to privileged EXEC mode.

     

    Configuring a VRF-Aware Server

    SUMMARY STEPS

      1.    enable

      2.    configure terminal

      3.    interface type number

      4.    ipv6 dhcp server vrf enable

      5.    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 interface type number


      Example:
      Device(config)# interface gigabitethernet 0/0/0
       

      Specifies an interface type and number, and enters interface configuration mode.

       
      Step 4 ipv6 dhcp server vrf enable


      Example:
      Device(config-if)# ipv6 dhcp server vrf enable
       

      Enables the DHCPv6 server VRF-aware feature on an interface.

       
      Step 5 end


      Example:
      Device(config-if)# end
       

      Returns to privileged EXEC mode.

       

      Configuration Examples for DHCPv6 Server - MPLS VPN Support

      Example: Configuring a VRF-Aware Relay

      Device# show ipv6 dhcp relay binding

Relay Bindings associated with default vrf:
Prefix: 2001:DB8:0:1::/64 (Ethernet0/0)
  DUID: 00030001AABBCC006500
  IAID: 196609
  lifetime: 2592000
  expiration: 12:34:28 IST Oct 14 2010
Summary:
  Total number of Relay bindings = 1
  Total number of Relay bindings added by Bulk lease = 0
RELAY#

      Example: Configuring a VRF-Aware Server

      Device# show ipv6 dhcp binding

Client: FE80::A8BB:CCFF:FE00:6400
  DUID: 00030001AABBCC006400
  VRF : global
  Interface : Ethernet0/0
  IA PD: IA ID 0x00030001, T1 302400, T2 483840
    Prefix: 2001::1/64
            preferred lifetime 604800, valid lifetime 2592000
            expires at Oct 15 2010 03:18 PM (2591143 seconds)

Device# show ipv6 route static

IPv6 Routing Table - default - 4 entries
Codes: C - Connected, L - Local, S - Static, U - Per-user Static route
       B - BGP, R - RIP, I1 - ISIS L1, I2 - ISIS L2
       IA - ISIS interarea, IS - ISIS summary, D - EIGRP, EX - EIGRP external
       ND - Neighbor Discovery
       O - OSPF Intra, OI - OSPF Inter, OE1 - OSPF ext 1, OE2 - OSPF ext 2
       ON1 - OSPF NSSA ext 1, ON2 - OSPF NSSA ext 2
S   2001::/64 [1/0]
     via FE80::A8BB:CCFF:FE00:6400, Ethernet0/0

      Additional References

      Related Documents

      Related Topic

      Document Title

      IPv6 addressing and connectivity

      IPv6 Configuration Guide

      Cisco IOS commands

      Cisco IOS Master Command List, All Releases

      IPv6 commands

      Cisco IOS IPv6 Command Reference

      Cisco IOS IPv6 features

      Cisco IOS IPv6 Feature Mapping

      Standards and RFCs

      Standard/RFC

      Title

      RFCs for IPv6

      IPv6 RFCs

      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 DHCPv6 Relay and Server - MPLS VPN Support

      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 DHCPv6 Relay and Server - MPLS VPN Support

      Feature Name

      Releases

      Feature Information

      VRF aware DHCPv6 relay

      15.2(1)SY

      The VRF aware DHCPv6 relay feature ensures that the DHCPv6 relay involved in forwarding IP addresses is VRF aware.