IP Multicast: PIM Configuration Guide, Cisco IOS Release 15SY
Configuring Basic IP Multicast in IPv6 Networks
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Configuring Basic IP Multicast in IPv6 Networks

Contents

Configuring Basic IP Multicast in IPv6 Networks

This module describes how to configure basic IP multicast in an IPv6 network.

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 Configuring Basic IP Multicast

  • To determine which of the tasks contained in this module you will have to perform, you must decide which Protocol Independent Multicast (PIM) mode will be used. This determination is based on the applications you intend to support on your network.
  • All access lists to be used with the tasks in this module should be configured prior to beginning the configuration task. For information about how to configure an access list, see the “Creating an IP Access List and Applying It to an Interface” module of the Security Configuration Guide: Access Control Lists guide.

Information About Configuring Basic IP Multicast in IPv6 Networks

IPv6 Multicast

IPv6 Multicast Overview

An IPv6 multicast group is an arbitrary group of receivers that want to receive a particular data stream. This group has no physical or geographical boundaries--receivers can be located anywhere on the Internet or in any private network. Receivers that are interested in receiving data flowing to a particular group must join the group by signaling their local device. This signaling is achieved with the MLD protocol.

Devices use the MLD protocol to learn whether members of a group are present on their directly attached subnets. Hosts join multicast groups by sending MLD report messages. The network then delivers data to a potentially unlimited number of receivers, using only one copy of the multicast data on each subnet. IPv6 hosts that wish to receive the traffic are known as group members.

Packets delivered to group members are identified by a single multicast group address. Multicast packets are delivered to a group using best-effort reliability, just like IPv6 unicast packets.

The multicast environment consists of senders and receivers. Any host, regardless of whether it is a member of a group, can send to a group. However, only the members of a group receive the message.

A multicast address is chosen for the receivers in a multicast group. Senders use that address as the destination address of a datagram to reach all members of the group.

Membership in a multicast group is dynamic; hosts can join and leave at any time. There is no restriction on the location or number of members in a multicast group. A host can be a member of more than one multicast group at a time.

How active a multicast group is, its duration, and its membership can vary from group to group and from time to time. A group that has members may have no activity.

IPv6 Multicast Addressing

An IPv6 multicast address is an IPv6 address that has a prefix of FF00::/8 (1111 1111). An IPv6 multicast address is an identifier for a set of interfaces that typically belong to different nodes. A packet sent to a multicast address is delivered to all interfaces identified by the multicast address. The second octet following the prefix defines the lifetime and scope of the multicast address. A permanent multicast address has a lifetime parameter equal to 0; a temporary multicast address has a lifetime parameter equal to 1. A multicast address that has the scope of a node, link, site, or organization, or a global scope has a scope parameter of 1, 2, 5, 8, or E, respectively. For example, a multicast address with the prefix FF02::/16 is a permanent multicast address with a link scope. The figure below shows the format of the IPv6 multicast address.

Figure 1. IPv6 Multicast Address Format

IPv6 nodes (hosts and routers) are required to join (receive packets destined for) the following multicast groups:

  • All-nodes multicast group FF02:0:0:0:0:0:0:1 (scope is link-local)
  • Solicited-node multicast group FF02:0:0:0:0:1:FF00:0000/104 for each of its assigned unicast and anycast addresses

IPv6 routers must also join the all-routers multicast group FF02:0:0:0:0:0:0:2 (scope is link-local).

The solicited-node multicast address is a multicast group that corresponds to an IPv6 unicast or anycast address. IPv6 nodes must join the associated solicited-node multicast group for every unicast and anycast address to which it is assigned. The IPv6 solicited-node multicast address has the prefix FF02:0:0:0:0:1:FF00:0000/104 concatenated with the 24 low-order bits of a corresponding IPv6 unicast or anycast address (see the figure below). For example, the solicited-node multicast address corresponding to the IPv6 address 2037::01:800:200E:8C6C is FF02::1:FF0E:8C6C. Solicited-node addresses are used in neighbor solicitation messages.

Figure 2. IPv6 Solicited-Node Multicast Address Format


Note


There are no broadcast addresses in IPv6. IPv6 multicast addresses are used instead of broadcast addresses.


IPv6 Multicast Groups

An IPv6 address must be configured on an interface before the interface can forward IPv6 traffic. Configuring a site-local or global IPv6 address on an interface automatically configures a link-local address and activates IPv6 for that interface. Additionally, the configured interface automatically joins the following required multicast groups for that link:

  • Solicited-node multicast group FF02:0:0:0:0:1:FF00::/104 for each unicast and anycast address assigned to the interface

    Note


    The solicited-node multicast address is used in the neighbor discovery process.


  • All-nodes link-local multicast group FF02::1
  • All-routers link-local multicast group FF02::2
IPv6 Multicast Address Group Range Support

This feature provides an access control mechanism for IPv6 multicast edge routing. The ACL specifies the multicast groups or channels that are to be permitted or denied. For groups or channels that are denied, the device ignores protocol traffic and actions (for example, no MLD states are created, no mroute states are created, no PIM joins are forwarded), and drops data traffic on all interfaces in the system, disabling multicast for groups or channels denied by the ACL.

Scoped Address Architecture

IPv6 includes support for global and nonglobal addresses. This section describes the usage of IPv6 addresses of different scopes.

A scope zone, or a simply a zone, is a connected region of topology of a given scope. For example, the set of links connected by devices within a particular site, and the interfaces attached to those links, comprise a single zone of site-local scope.

A zone is a particular instance of a topological region (for example, Zone1’s site or Zone2’s site), whereas a scope is the size of a topological region (for example, a site or a link). The zone to which a particular nonglobal address pertains is not encoded in the address itself, but rather is determined by context, such as the interface from which it is sent or received. Therefore, addresses of a given nonglobal scope may be reused in different zones of that scope. For example, Zone1’s site and Zone2’s site may each contain a node with site-local address FEC0::1.

Zones of the different scopes are instantiated as follows:
  • Each link, and the interfaces attached to that link, comprises a single zone of link-local scope (for both unicast and multicast).
  • There is a single zone of global scope (for both unicast and multicast), comprising all the links and interfaces in the Internet.
  • The boundaries of zones of scope other than interface-local, link-local, and global must be defined and configured by network administrators. A site boundary serves as such for both unicast and multicast.

Zone boundaries are relatively static features and do not change in response to short-term changes in topology. Therefore, the requirement that the topology within a zone be "connected" is intended to include links and interfaces that may be connected only occasionally. For example, a residential node or network that obtains Internet access by dialup to an employer’s site may be treated as part of the employer’s site-local zone even when the dialup link is disconnected. Similarly, a failure of a device, interface, or link that causes a zone to become partitioned does not split that zone into multiple zones; rather, the different partitions are still considered to belong to the same zone.

Zones have the following additional properties:
  • Zone boundaries cut through nodes, not links (the global zone has no boundary, and the boundary of an interface-local zone encloses just a single interface.)
  • Zones of the same scope cannot overlap; that is, they can have no links or interfaces in common.
  • A zone of a given scope (less than global) falls completely within zones of larger scope; that is, a smaller scope zone cannot include more topology than any larger scope zone with which it shares any links or interfaces.
  • Each interface belongs to exactly one zone of each possible scope.

MRIB

The Multicast Routing Information Base (MRIB) is a protocol-independent repository of multicast routing entries instantiated by multicast routing protocols (routing clients). Its main function is to provide independence between routing protocols and the Multicast Forwarding Information Base (MFIB). It also acts as a coordination and communication point among its clients.

Routing clients use the services provided by the MRIB to instantiate routing entries and retrieve changes made to routing entries by other clients. Besides routing clients, MRIB also has forwarding clients (MFIB instances) and special clients such as MLD. MFIB retrieves its forwarding entries from MRIB and notifies the MRIB of any events related to packet reception. These notifications can either be explicitly requested by routing clients or spontaneously generated by the MFIB.

Another important function of the MRIB is to allow for the coordination of multiple routing clients in establishing multicast connectivity within the same multicast session. MRIB also allows for the coordination between MLD and routing protocols.

IPv6 Multicast Process Switching and Fast Switching

A unified MFIB is used to provide both fast switching and process switching support for PIM-SM and PIM-SSM in IPv6 multicast. In process switching, the Route Processor must examine, rewrite, and forward each packet. The packet is first received and copied into the system memory. The device then looks up the Layer 3 network address in the routing table. The Layer 2 frame is then rewritten with the next-hop destination address and sent to the outgoing interface. The RP also computes the cyclic redundancy check (CRC). This switching method is the least scalable method for switching IPv6 packets.

IPv6 multicast fast switching allows devices to provide better packet forwarding performance than process switching. Information conventionally stored in a route cache is stored in several data structures for IPv6 multicast switching. The data structures provide optimized lookup for efficient packet forwarding.

In IPv6 multicast forwarding, the first packet is fast-switched if the PIM protocol logic allows it. In IPv6 multicast fast switching, the MAC encapsulation header is precomputed. IPv6 multicast fast switching uses the MFIB to make IPv6 destination prefix-based switching decisions. In addition to the MFIB, IPv6 multicast fast switching uses adjacency tables to prepend Layer 2 addressing information. The adjacency table maintains Layer 2 next-hop addresses for all MFIB entries.

The adjacency table is populated as adjacencies are discovered. Each time an adjacency entry is created (such as through ARP), a link-layer header for that adjacent node is precomputed and stored in the adjacency table. Once a route is determined, it points to a next hop and corresponding adjacency entry. It is subsequently used for encapsulation during switching of packets.

A route might have several paths to a destination prefix, such as when a device is configured for simultaneous load balancing and redundancy. For each resolved path, a pointer is added for the adjacency corresponding to the next-hop interface for that path. This mechanism is used for load balancing across several paths.

IPv6 Anycast RP Solution

PIMv6 Anycast RP Solution Overview

The anycast RP solution in IPv6 PIM allows an IPv6 network to support anycast services for the PIM-SM RP. It allows anycast RP to be used inside a domain that runs PIM only. Anycast RP can be used in IPv4 as well as IPv6, but it does not depend on the Multicast Source Discovery Protocol (MSDP), which runs only on IPv4. This feature is useful when interdomain connection is not required.

Anycast RP is a mechanism that ISP-based backbones use to get fast convergence when a PIM RP device fails. To allow receivers and sources to rendezvous to the closest RP, the packets from a source need to get to all RPs to find joined receivers.

A unicast IP address is chosen as the RP address. This address is either statically configured or distributed using a dynamic protocol to all PIM devices throughout the domain. A set of devices in the domain is chosen to act as RPs for this RP address; these devices are called the anycast RP set. Each device in the anycast RP set is configured with a loopback interface using the RP address. Each device in the anycast RP set also needs a separate physical IP address to be used for communication between the RPs.

The RP address, or a prefix that covers the RP address, is injected into the unicast routing system inside of the domain. Each device in the anycast RP set is configured with the addresses of all other devices in the anycast RP set, and this configuration must be consistent in all RPs in the set.

PIMv6 Anycast RP Normal Operation

The following illustration shows PIMv6 anycast RP normal operation and assumes the following:
  • RP1, RP2, RP3, and RP4 are members in the same anycast RP group.
  • S11 and S31 are sources that use RP1 and RP3, respectively, based on their unicast routing metric.
  • R11, R12, R2, R31, and R32 are receivers. Based on their unicast routing metrics, R11 and R12 join to RP1, R2 joins to RP2 and R31, and R32 joins to RP3, respectively.

The following sequence of events occurs when S11 starts sending packets:

  1. DR1 creates (S,G) states and sends a register to RP1. DR1 may also encapsulate the data packet in the register.
  2. Upon receiving the register, RP1 performs normal PIM-SM RP functionality, and forwards the packets to R11 and R12.
  3. RP1 also sends the register (which may encapsulate the data packets) to RP2, RP3, and RP4.
  4. RP2, RP3, and RP4 do not further forward the register to each other.
  5. RP2, RP3, and RP4 perform normal PIM-SM RP functionality, and if there is a data packet encapsulated, RP2 forwards the data packet to R2 and RP3 forwards the data packet to R31 and R32, respectively.
  6. The previous five steps repeat for null registers sent by DR1.

PIMv6 Anycast RP Failover

The following illustration shows PIM anycast RP failover.

In failover, when RP1 is not reachable, the following occurs:
  • Registers from DR1 will be routed transparently to RP2.
  • R11 uses RP2 as the RP, and R12 uses RP4 as the RP.
  • Registers from DR1 will be routed from RP2 to RP3 and RP4.

In this way, the loss of the RP (RP1 in this case) is transparent to DR1, R11, and R12, and the network can converge as soon as the IGP is converged.

IPv6 BSR

IPv6 BSR

PIM devices in a domain must be able to map each multicast group to the correct RP address. The BSR protocol for PIM-SM provides a dynamic, adaptive mechanism to distribute group-to-RP mapping information rapidly throughout a domain. With the IPv6 BSR feature, if an RP becomes unreachable, it will be detected and the mapping tables will be modified so that the unreachable RP is no longer used, and the new tables will be rapidly distributed throughout the domain.

Every PIM-SM multicast group needs to be associated with the IP or IPv6 address of an RP. When a new multicast sender starts sending, its local DR will encapsulate these data packets in a PIM register message and send them to the RP for that multicast group. When a new multicast receiver joins, its local DR will send a PIM join message to the RP for that multicast group. When any PIM device sends a (*, G) join message, the PIM device needs to know which is the next device toward the RP so that G (Group) can send a message to that device. Also, when a PIM device is forwarding data packets using (*, G) state, the PIM device needs to know which is the correct incoming interface for packets destined for G, because it needs to reject any packets that arrive on other interfaces.

A small set of devices from a domain are configured as candidate bootstrap routers (C-BSRs) and a single BSR is selected for that domain. A set of devices within a domain are also configured as candidate RPs (C-RPs); typically, these devices are the same devices that are configured as C-BSRs. Candidate RPs periodically unicast candidate-RP-advertisement (C-RP-Adv) messages to the BSR of that domain, advertising their willingness to be an RP. A C-RP-Adv message includes the address of the advertising C-RP, and an optional list of group addresses and mask length fields, indicating the group prefixes for which the candidacy is advertised. The BSR then includes a set of these C-RPs, along with their corresponding group prefixes, in bootstrap messages (BSMs) it periodically originates. BSMs are distributed hop-by-hop throughout the domain.

Bidirectional BSR support allows bidirectional RPs to be advertised in C-RP messages and bidirectional ranges in the BSM. All devices in a system must be able to use the bidirectional range in the BSM; otherwise, the bidirectional RP feature will not function.

IPv6 BSR: Configure RP Mapping

The IPv6 BSR ability to configure RP mapping allows IPv6 multicast devices to be statically configured to announce scope-to-RP mappings directly from the BSR instead of learning them from candidate-RP messages. Announcing RP mappings from the BSR is useful in several situations:

  • When an RP address never changes because there is only a single RP or the group range uses an anycast RP, it may be less complex to configure the RP address announcement statically on the candidate BSRs.
  • When an RP address is a virtual RP address (such as when using bidirectional PIM), it cannot be learned by the BSR from a candidate-RP. Instead, the virtual RP address must be configured as an announced RP on the candidate BSRs.

IPv6 BSR: Scoped Zone Support

BSR provides scoped zone support by distributing group-to-RP mappings in networks using administratively scoped multicast. The user can configure candidate BSRs and a set of candidate RPs for each administratively scoped region in the user’s domain.

For BSR to function correctly with administrative scoping, a BSR and at least one C-RP must be within every administratively scoped region. Administratively scoped zone boundaries must be configured at the zone border devices, because they need to filter PIM join messages that might inadvertently cross the border due to error conditions. In addition, at least one C-BSR within the administratively scoped zone must be configured to be a C-BSR for the administratively scoped zone’s address range.

A separate BSR election will then take place (using BSMs) for every administratively scoped range, plus one for the global range. Administratively scoped ranges are identified in the BSM because the group range is marked to indicate that this is an administrative scope range, not just a range that a particular set of RPs is configured to handle.

Unless the C-RP is configured with a scope, it discovers the existence of the administratively scoped zone and its group range through reception of a BSM from the scope zone’s elected BSR containing the scope zone’s group range. A C-RP stores each elected BSR's address and the administratively scoped range contained in its BSM. It separately unicasts C-RP-Adv messages to the appropriate BSR for every administratively scoped range within which it is willing to serve as an RP.

All PIM devices within a PIM bootstrap domain where administratively scoped ranges are in use must be able to receive BSMs and store the winning BSR and RP set for all administratively scoped zones that apply.

IPv6 Multicast: RPF Flooding of BSR Packets

Cisco IPv6 devices provide support for the RPF flooding of BSR packets so that the device will not disrupt the flow of BSMs. The device will recognize and parse enough of the BSM to identify the BSR address. The device performs an RPF check for this BSR address and forwards the packet only if it is received on the RPF interface. The device also creates a BSR entry containing RPF information to use for future BSMs from the same BSR. When BSMs from a given BSR are no longer received, the BSR entry is timed out.

IPv6 Multicast Groups

An IPv6 address must be configured on an interface before the interface can forward IPv6 traffic. Configuring a site-local or global IPv6 address on an interface automatically configures a link-local address and activates IPv6 for that interface. Additionally, the configured interface automatically joins the following required multicast groups for that link:

  • Solicited-node multicast group FF02:0:0:0:0:1:FF00::/104 for each unicast and anycast address assigned to the interface

    Note


    The solicited-node multicast address is used in the neighbor discovery process.


  • All-nodes link-local multicast group FF02::1
  • All-routers link-local multicast group FF02::2

IPv6 Multicast Address Group Range Support

This feature provides an access control mechanism for IPv6 multicast edge routing. The ACL specifies the multicast groups or channels that are to be permitted or denied. For groups or channels that are denied, the device ignores protocol traffic and actions (for example, no MLD states are created, no mroute states are created, no PIM joins are forwarded), and drops data traffic on all interfaces in the system, disabling multicast for groups or channels denied by the ACL.

How to Configure Basic IP Multicast in IPv6 Networks

Enabling IPv6 Multicast Routing

IPv6 multicast uses MLD version 2. This version of MLD is fully backward-compatible with MLD version 1 (described in RFC 2710). Hosts that support only MLD version 1 will interoperate with a device running MLD version 2. Mixed LANs with both MLD version 1 and MLD version 2 hosts are likewise supported.

Before You Begin

You must first enable IPv6 unicast routing on all interfaces of the device on which you want to enable IPv6 multicast routing .

SUMMARY STEPS

    1.    enable

    2.    configure terminal

    3.    ipv6 multicast-routing [vrf vrf-name]


DETAILED STEPS
      Command or Action Purpose
    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 multicast-routing [vrf vrf-name]


    Example:
    Device(config)# ipv6 multicast-routing
     

    Enables multicast routing on all IPv6-enabled interfaces and enables multicast forwarding for PIM and MLD on all enabled interfaces of the device.

    • IPv6 multicast routing is disabled by default when IPv6 unicast routing is enabled. On certain devices, the IPv6 multicast routing must also be enabled in order to use IPv6 unicast routing.
     

    Disabling the Device from Receiving Unauthenticated Multicast Traffic

    In some situations, access control may be needed to prevent multicast traffic from being received unless the subscriber is authenticated and the channels are authorized as per access control profiles. That is, there should be no traffic at all unless specified otherwise by access control profiles.

    Perform this task to disable the device from receiving multicast traffic to be received from unauthenticated groups or unauthorized channels.

    SUMMARY STEPS

      1.    enable

      2.    configure terminal

      3.    ipv6 multicast [vrf vrf-name] group-range[access-list-name]


    DETAILED STEPS
        Command or Action Purpose
      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 multicast [vrf vrf-name] group-range[access-list-name]


      Example:
      Device(config)# ipv6 multicast group-range
       

      Disables multicast protocol actions and traffic forwarding for unauthorized groups or channels on all the interfaces in a device.

       

      Troubleshooting IPv6 Multicast

      SUMMARY STEPS

        1.    enable

        2.    debug ipv6 mfib group-name | group-address] [adjacency | signal | db | init | mrib | pak | ps

        3.    debug ipv6 mld [group-name | group-address | interface-type]

        4.    debug ipv6 mld explicit [group-name | group-address

        5.    debug ipv6 pim [group-name | group-address | interface-type | neighbor | bsr

        6.    debug bgp ipv6 {unicast | multicast} dampening [prefix-list prefix-list-name

        7.    debug bgp ipv6 {unicast | multicast} updates [ipv6-address] [prefix-list prefix-list-name] [in | out

        8.    debug ipv6 mrib client

        9.    debug ipv6 mrib io

        10.    debug ipv6 mrib issu

        11.    debug ipv6 mrib proxy

        12.    debug ipv6 mrib route [group-name | group-address

        13.    debug ipv6 mrib table


      DETAILED STEPS
          Command or Action Purpose
        Step 1 enable


        Example:
        Device> enable
         

        Enables privileged EXEC mode.

        • Enter your password if prompted.
         
        Step 2 debug ipv6 mfib group-name | group-address] [adjacency | signal | db | init | mrib | pak | ps


        Example:
        Device# debug ipv6 mfib pak FF04::10
         

        Enables debugging output on the IPv6 MFIB.

         
        Step 3 debug ipv6 mld [group-name | group-address | interface-type]

        Example:
        Device# debug ipv6 mld
         

        Enables debugging on MLD protocol activity.

         
        Step 4 debug ipv6 mld explicit [group-name | group-address


        Example:
        Device# debug ipv6 mld explicit
         

        Displays information related to the explicit tracking of hosts.

         
        Step 5 debug ipv6 pim [group-name | group-address | interface-type | neighbor | bsr


        Example:
        Device# debug ipv6 pim
         

        Enables debugging on PIM protocol activity.

         
        Step 6 debug bgp ipv6 {unicast | multicast} dampening [prefix-list prefix-list-name


        Example:
        Device# debug bgp ipv6 multicast
         

        Displays debugging messages for IPv6 BGP dampening.

         
        Step 7 debug bgp ipv6 {unicast | multicast} updates [ipv6-address] [prefix-list prefix-list-name] [in | out


        Example:
        Device# debug bgp ipv6 multicast updates
         

        Displays debugging messages for IPv6 BGP update packets.

         
        Step 8 debug ipv6 mrib client


        Example:
        Device# debug ipv6 mrib client
         

        Enables debugging on MRIB client management activity.

         
        Step 9 debug ipv6 mrib io


        Example:
        Device# debug ipv6 mrib io
         

        Enables debugging on MRIB I/O events.

         
        Step 10 debug ipv6 mrib issu


        Example:
        Device# debug ipv6 mrib issu
         

        Enables debugging on MRIB in service software update.

         
        Step 11 debug ipv6 mrib proxy


        Example:
        Device# debug ipv6 mrib proxy
         

        Enables debugging on MRIB proxy activity between the route processor and line cards on distributed devices.

         
        Step 12 debug ipv6 mrib route [group-name | group-address


        Example:
        Device# debug ipv6 mrib route 
         

        Displays information about MRIB routing entry-related activity.

         
        Step 13 debug ipv6 mrib table


        Example:
        Device# debug ipv6 mrib table
         

        Enables debugging on MRIB table management activity.

         

        Configuring PIMv6 Anycast RP

        This task describes how to configure two PIMv6 anycast RP peers. Steps 3 through 11 show the configuration for RP1, and Steps 12 through 19 show the configuration for RP2.

        SUMMARY STEPS

          1.    enable

          2.    configure terminal

          3.    ipv6 pim [vrf vrf-name] rp-address ipv6-address [group-address-list ] [bidir]

          4.    interface type number

          5.    ipv6 address {ipv6-address/prefix-length | prefix-name sub-bits /prefix-length}

          6.    no shut

          7.    interface type number

          8.    ipv6 address {ipv6-address/prefix-length | prefix-name sub-bits /prefix-length}

          9.    no shut

          10.    exit

          11.    ipv6 pim anycast-RP rp-address peer-address

          12.    ipv6 pim [vrf vrf-name] rp-address ipv6-address [group-address-list ] [bidir]

          13.    interface type number

          14.    ipv6 address {ipv6-address/prefix-length | prefix-name sub-bits /prefix-length}

          15.    no shut

          16.    interface type number

          17.    ipv6 address {ipv6-address/prefix-length | prefix-name sub-bits /prefix-length}

          18.    no shut

          19.    ipv6 pim anycast-RP rp-address peer-address


        DETAILED STEPS
            Command or Action Purpose
          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 pim [vrf vrf-name] rp-address ipv6-address [group-address-list ] [bidir]


          Example:
          Device(config)# ipv6 pim rp-address 2001:DB8::1:1 acl_sparse1
           

          Configures the address of a PIM RP for a particular group range.

           
          Step 4 interface type number


          Example:
          Device(config)# interface Loopback4
           

          Specifies an interface type and number, and places the device in interface configuration mode.

           
          Step 5 ipv6 address {ipv6-address/prefix-length | prefix-name sub-bits /prefix-length}


          Example:
          Device(config-if)# ipv6 address 2001:DB8::4:4/64
           

          Configures an IPv6 address based on an IPv6 general prefix and enable IPv6 processing on an interface.

           
          Step 6 no shut


          Example:
          Device(config-if)# no shut
           

          Enables an interface.

           
          Step 7 interface type number


          Example:
          Device(config-if)# interface Loopback5
           

          Specifies an interface type and number, and places the device in interface configuration mode.

           
          Step 8 ipv6 address {ipv6-address/prefix-length | prefix-name sub-bits /prefix-length}


          Example:
          Device(config-if)# ipv6 address 2001:DB8:0:ABCD::1/64
           

          Configures an IPv6 address based on an IPv6 general prefix and enable IPv6 processing on an interface.

           
          Step 9 no shut


          Example:
          Device(config-if)# no shut
           

          Enables an interface.

           
          Step 10 exit


          Example:
          Device(config-if)# exit
           

          Enter this command to exit interface configuration mode and enter global configuration mode.

           
          Step 11 ipv6 pim anycast-RP rp-address peer-address


          Example:
          Device(config)# ipv6 pim anycast-rp 2001:DB8:0:ABCD::1 2001:DB8::3:3
           

          Use this command to configure the address of the PIM RP for an anycast group range.

           
          Step 12 ipv6 pim [vrf vrf-name] rp-address ipv6-address [group-address-list ] [bidir]


          Example:
          Device(config)# ipv6 pim rp-address 2001:DB8::1:1 acl_sparse1
           

          Configures the address of a PIM RP for a particular group range.

           
          Step 13 interface type number


          Example:
          Device(config)# interface Loopback4
           

          Specifies an interface type and number, and places the device in interface configuration mode.

           
          Step 14 ipv6 address {ipv6-address/prefix-length | prefix-name sub-bits /prefix-length}


          Example:
          Device(config-if)# ipv6 address 2001:DB8::3:3/64
           

          Configures an IPv6 address based on an IPv6 general prefix and enables IPv6 processing on an interface.

           
          Step 15 no shut


          Example:
          Device(config-if)# no shut
           

          Enables an interface.

           
          Step 16 interface type number


          Example:
          Device(config-if)# interface Loopback5
           

          Specifies an interface type and number, and places the device in interface configuration mode.

           
          Step 17 ipv6 address {ipv6-address/prefix-length | prefix-name sub-bits /prefix-length}


          Example:
          Device(config-if)# ipv6 address 2001:DB8:0:ABCD::1/64
           

          Configures an IPv6 address based on an IPv6 general prefix and enables IPv6 processing on an interface.

           
          Step 18 no shut


          Example:
          Device(config-if)# no shut
           

          Enables an interface

           
          Step 19 ipv6 pim anycast-RP rp-address peer-address


          Example:
          Device(config-if)# ipv6 pim anycast-rp 2001:DB8::1:1 2001:DB8::4:4
           

          Use this command to configure the address of the PIM RP for an anycast group range.

           

          Configuring a BSR and Verifying BSR Information

          SUMMARY STEPS

            1.    enable

            2.    configure terminal

            3.    ipv6 pim [vrf vrf-name] bsr candidate bsr ipv6-address[hash-mask-length] [priority priority-value]

            4.    interface type number

            5.    ipv6 pim bsr border

            6.    end

            7.    show ipv6 pim [vrf vrf-name] bsr {election | rp-cache | candidate-rp}


          DETAILED STEPS
              Command or Action Purpose
            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 pim [vrf vrf-name] bsr candidate bsr ipv6-address[hash-mask-length] [priority priority-value]


            Example:
            Device(config)# ipv6 pim bsr candidate bsr 2001:DB8:3000:3000::42 124 priority 10
             

            Configures a device to be a candidate BSR.

             
            Step 4 interface type number


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

            Specifies an interface type and number, and places the device in interface configuration mode.

             
            Step 5 ipv6 pim bsr border


            Example:
            Device(config-if)# ipv6 pim bsr border
             

            Configures a border for all BSMs of any scope on a specified interface.

             
            Step 6 end


            Example:
            Device(config-if)# end
             

            Exits to privileged EXEC mode.

             
            Step 7 show ipv6 pim [vrf vrf-name] bsr {election | rp-cache | candidate-rp}


            Example:
            Device# show ipv6 pim bsr election
             

            Displays information related to PIM BSR protocol processing.

             

            Sending PIM RP Advertisements to the BSR

            SUMMARY STEPS

              1.    enable

              2.    configure terminal

              3.    ipv6 pim [vrf vrf-name] bsr candidate rp ipv6-address [group-list access-list-name] [priority priority-value] [interval seconds] [scope scope-value] [bidir]

              4.    interface type number

              5.    ipv6 pim bsr border


            DETAILED STEPS
                Command or Action Purpose
              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 pim [vrf vrf-name] bsr candidate rp ipv6-address [group-list access-list-name] [priority priority-value] [interval seconds] [scope scope-value] [bidir]


              Example:
              Device(config)# ipv6 pim bsr candidate rp 2001:DB8:3000:3000::42 priority 0
               

              Sends PIM RP advertisements to the BSR.

               
              Step 4 interface type number


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

              Specifies an interface type and number, and places the device in interface configuration mode.

               
              Step 5 ipv6 pim bsr border


              Example:
              Device(config-if)# ipv6 pim bsr border
               

              Configures a border for all BSMs of any scope on a specified interface.

               

              Configuring BSR for Use Within Scoped Zones

              A user can configure candidate BSRs and a set of candidate RPs for each administratively scoped region in the domain.

              If scope is specified on the candidate RP, then this device will advertise itself as C-RP only to the BSR for the specified scope. If the group list is specified along with the scope, then only prefixes in the access list with the same scope as that configured will be advertised.

              If a scope is specified on the bootstrap device, the BSR will originate BSMs including the group range associated with the scope and accept C-RP announcements for groups that belong to the given scope.

              SUMMARY STEPS

                1.    enable

                2.    configure terminal

                3.    ipv6 pim [vrf vrf-name] bsr candidate bsr ipv6-address [hash-mask-length] [priority priority-value]

                4.    ipv6 pim [vrf vrf-name] bsr candidate rp ipv6-address [group-list access-list-name] [priority priority-value] [interval seconds] [scope scope-value] [bidir]

                5.    interface type number

                6.    ipv6 multicast boundary scope scope-value


              DETAILED STEPS
                  Command or Action Purpose
                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 pim [vrf vrf-name] bsr candidate bsr ipv6-address [hash-mask-length] [priority priority-value]


                Example:
                Device(config)# ipv6 pim bsr candidate bsr 2001:DB8:1:1:4 
                 

                Configures a device to be a candidate BSR.

                 
                Step 4 ipv6 pim [vrf vrf-name] bsr candidate rp ipv6-address [group-list access-list-name] [priority priority-value] [interval seconds] [scope scope-value] [bidir]


                Example:
                Device(config)# ipv6 pim bsr candidate rp 2001:DB8:1:1:1 group-list list scope 6
                 

                Configures the candidate RP to send PIM RP advertisements to the BSR.

                 
                Step 5 interface type number


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

                Specifies an interface type and number, and places the device in interface configuration mode.

                 
                Step 6 ipv6 multicast boundary scope scope-value


                Example:
                Device(config-if)# ipv6 multicast boundary scope 6
                 

                Configures a multicast boundary on the interface for a specified scope.

                 

                Configuring BSR Devices to Announce Scope-to-RP Mappings

                IPv6 BSR devices can be statically configured to announce scope-to-RP mappings directly instead of learning them from candidate-RP messages. A user might want to configure a BSR device to announce scope-to-RP mappings so that an RP that does not support BSR is imported into the BSR. Enabling this feature also allows an RP positioned outside the enterprise’s BSR domain to be learned by the known remote RP on the local candidate BSR devices.

                SUMMARY STEPS

                  1.    enable

                  2.    configure terminal

                  3.    ipv6 pim [vrf vrf-name] bsr announced rp ipv6-address [group-list access-list-name] [priority priority-value] [bidir] [scope scope-value]


                DETAILED STEPS
                    Command or Action Purpose
                  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 pim [vrf vrf-name] bsr announced rp ipv6-address [group-list access-list-name] [priority priority-value] [bidir] [scope scope-value]


                  Example:
                  Device(config)# ipv6 pim bsr announced rp 2001:DB8:3000:3000::42 priority 0
                   

                  Announces scope-to-RP mappings directly from the BSR for the specified candidate RP.

                   

                  Configuration Examples for Configuring IP Multicast Basic in IPv6 Networks

                  Example: Enabling IPv6 Multicast Routing

                  The following example enables multicast routing on all interfaces and also enables multicast forwarding for PIM and MLD on all enabled interfaces of the device.

                  Device> enable
                  Device# configure terminal
                  Device(config)# ipv6 multicast-routing
                  

                  Examples: Disabling IPv6 Multicast Address Group Range Support

                  The following example ensures that the device disables multicast for groups or channels denied by an access list named list2:

                          ipv6 multicast group-range list2

                  The following example shows that the command in the previous example is overridden on an interface specified by int2. On int2, MLD states are created for groups or channels permitted by int-list2 but are not created for groups or channels denied by int-list2. On all other interfaces, the access-list named list2 is used for access control.

                  In this example, list2 can be specified to deny all or most multicast groups or channels, and int-list2 can be specified to permit authorized groups or channels only for interface int2.

                  Device(config)# interface int2
                  Device(config-if)# ipv6 mld access-group int-list2
                  

                  Example: Verifying IPv6 MRIB Information

                  The following example displays information about the IPv6 MRIB client:

                  Device# show ipv6 mrib client
                  
                  IP MRIB client-connections
                  igmp:145        (connection id 0)
                  pim:146 (connection id 1)
                  mfib ipv6:3     (connection id 2)
                  slot 3  mfib ipv6 rp agent:16   (connection id 3)
                  slot 1  mfib ipv6 rp agent:16   (connection id 4)
                  slot 0  mfib ipv6 rp agent:16   (connection id 5)
                  slot 4  mfib ipv6 rp agent:16   (connection id 6)
                  slot 2  mfib ipv6 rp agent:16   (connection id 7)

                  The following example displays summary information about the IPv6 MRIB route:

                  Device# show ipv6 mrib route summary
                  
                  MRIB Route-DB Summary 
                    No. of (*,G) routes = 52
                    No. of (S,G) routes = 0
                    No. of Route x Interfaces (RxI) = 10

                  Example: Configuring PIMv6 Anycast RP

                  RP1
                  Device1(config)# ipv6 pim rp-address 2001:DB8::1:1 acl_sparse1
                  Device1(config)# interface Loopback4
                  Device1(config-if)# ipv6 address 2001:DB8::4:4/64
                  Device1(config-if)# no shut
                  
                  Device1(config)# interface Loopback5
                  Device1(config-if)# ipv6 address 2001:DB8:0:ABCD::1/64
                  Device1(config-if)# no shut
                  Device1(config-if)# exit
                  Device1(config)# ipv6 pim anycast-rp 2001:DB8:0:ABCD::1 2001:DB8::3:3
                  
                  RP2 (Anycast RP Peer)
                  Device2(config)# ipv6 pim rp-address 2001:DB8::1:1 acl_sparse1
                  Device2(config)# interface Loopback4
                  Device2(config-if)# ipv6 address 2001:DB8::3:3/64
                  Device2(config-if)# no shut
                  
                  Device2(config)# interface Loopback5
                  Device2(config-if)# ipv6 address 2001:DB8:0:ABCD::1/64
                  Device2(config-if)# no shut
                  Device2(config)# ipv6 pim anycast-rp 2001:DB8::1:1 2001:DB8::4:4
                  
                  Device2 show ipv6 pim anycast-rp 2001:DB8::1:1
                  
                  Anycast RP Peers For 2001:DB8::1:1   Last Register/Register-Stop received
                    2001:DB8::3:3 00:00:00/00:00:00
                    2001:DB8::4:4 00:00:00/00:00:00
                  

                  Example: Configuring a BSR

                  Device# show ipv6 pim bsr election
                  
                  PIMv2 BSR information
                  BSR Election Information
                  Scope Range List: ff00::/8
                  This system is the Bootstrap Router (BSR)
                  BSR Address: 60::1:1:4
                  Uptime: 00:11:55, BSR Priority: 0, Hash mask length: 126
                  RPF: FE80::A8BB:CCFF:FE03:C400,Ethernet0/0
                  BS Timer: 00:00:07
                  This system is candidate BSR
                  Candidate BSR address: 60::1:1:4, priority: 0, hash mask length: 126
                        

                  Additional References

                  Related Documents

                  Related Topic

                  Document Title

                  IPv6 addressing and connectivity

                  IPv6 Configuration Guide

                  Cisco IOS commands

                  Cisco IOS Master Commands List, All Releases

                  IP multicast commands

                  Cisco IOS IP Multicast Command Reference

                  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 Configuring Basic IP Multicast in IPv6 Networks

                  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 Configuring Basic IP Multicast in IPv6 Networks

                  Feature Name

                  Releases

                  Feature Information

                  IPv6 Multicast

                  12.0(26)S

                  12.2(25)SG

                  12.2(33)SRA

                  12.2(18)SXE

                  12.3(2)T

                  12.4

                  12.4(2)T

                  15.0(2)SE

                  Cisco IOS XE Release 2.1

                  IPv6 multicast allows a host to send a single data stream to a subset of all hosts simultaneously.

                  The following commands were introduced or modified: clear ipv6 pim topology, debug ipv6 mld, debug ipv6 mrib, debug ipv6 pim, debug ipv6 pim neighbor, ipv6 mld join-group, ipv6 mld query-interval, ipv6 mld query-max-response-time, ipv6 mld query-timeout, ipv6 mld router, ipv6 mld static-group, ipv6 multicast-routing , ipv6 pim, ipv6 pim dr-priority, ipv6 pim hello-interval, ipv6 pim rp-address , ipv6 pim spt-threshold infinity , show ipv6 mld groups, show ipv6 mld groups summary, show ipv6 mld interface, show ipv6 mrib client, show ipv6 mrib route, show ipv6 mroute, show ipv6 pim group-map, show ipv6 pim interface, show ipv6 pim neighbor, show ipv6 pim range-list, show ipv6 pim topology, show ipv6 pim tunnel.

                  IPv6 Multicast Address Group Range Support

                  15.0(1)M

                  12.2(40)SG

                  3.2.0SG

                  15.0(2)SG

                  12.2(33)SRE

                  12.2(33)SXI

                  Cisco IOS XE Release 2.6

                  This feature is also known as Disable Group Ranges.

                  This feature provides an access control mechanism for IPv6 multicast edge routing.

                  The following commands were introduced or modified: ipv6 mld access-group, ipv6 multicast boundary scope, ipv6 multicast group-range.

                  IPv6 Multicast: Scope Boundaries

                  12.0(26)S

                  12.2(18)S

                  12.2(25)SG

                  12.2(33)SRA

                  12.3(2)T

                  12.4

                  12.4(2)T

                  15.0(1)S

                  IPv6 includes support for global and nonglobal addresses. This feature describes the usage of IPv6 addresses of different scopes.

                  PIMv6: Anycast RP Solution

                  15.1(3)S

                  Cisco IOS XE Release 3.4S

                  15.2(3)T

                  The anycast RP solution in IPv6 PIM enables an IPv6 network to support anycast services for the PIM-SM RP and allows anycast RP to be used inside a domain that runs PIM only.

                  The following commands were introduced or modified: ipv6 pim anycast-RP, show ipv6 pim anycast-RP.

                  IPv6 Multicast: Bootstrap Router

                  12.0(28)S

                  12.2(25)S

                  12.2(25)SG

                  12.2(33)SRA

                  12.2(33)SXH

                  12.3(11)T

                  12.4

                  12.4(2)T

                  Cisco IOS XE Release 2.4

                  15.0(1)S

                  If an RP becomes unreachable, this feature allows the RP to be detected and the mapping tables modified so that the unreachable RP is no longer used, and the new tables will be rapidly distributed throughout the domain.

                  The following commands were introduced or modified: debug ipv6 pim bsr, ipv6 pim bsr border, ipv6 pim bsr candidate bsr, ipv6 pim bsr candidate rp, show ipv6 pim bsr, show ipv6 pim group-map.

                  IPv6 BSR: Configure RP Mapping

                  12.2(33)SRE

                  12.2(50)SY

                  12.4(2)T

                  Cisco IOS XE Release 2.4

                  15.0(1)S

                  This feature allows IPv6 multicast devices to be statically configured to announce scope-to-RP mappings directly from the BSR instead of learning them from candidate-RP messages.

                  The following commands were introduced or modified: ipv6 multicast-routing, ipv6 pim bsr announced rp, ipv6 pim bsr candidate bsr.

                  IPv6 Multicast: RPF Flooding of BSR Packets

                  Cisco IOS XE Release 2.1

                  The RPF flooding of BSR packets feature enables a Cisco IPv6 device to not disrupt the flow of BSMs.

                  The following command was introduced: show ipv6 pim bsr.

                  IPv6 Multicast VRF Lite

                  15.1(4)M

                  Cisco IOS XE Release 3.4S

                  This feature provides IPv6 multicast support for multiple virtual routing/forwarding contexts (VRFs), the scope of which is limited to the device in which the VRFs are defined.