Cisco IOS XR Multicast Configuration Guide for the Cisco CRS-1 Router
Implementing Multicast Routing on Cisco IOS XR Software
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Implementing Multicast Routing on Cisco IOS XR Software Cisco ASR 9000 Series Routers

Table Of Contents

Implementing Multicast Routing on Cisco IOS XR Software Cisco ASR 9000 Series Routers

Contents

Prerequisites for Implementing Multicast Routing

Information About Implementing Multicast Routing

Key Protocols and Features Supported in the Cisco IOS XR Software Multicast Routing Implementation

Multicast Routing Functional Overview

Cisco IOS XR Multicast Routing Implementation

Internet Group Management Protocol and Multicast Listener Discovery

IGMP and MLD Versions

IGMP Routing Example

Protocol Independent Multicast

PIM-Sparse Mode

PIM-Source Specific Multicast

PIM Shared Tree and Source Tree (Shortest Path Tree)

Multicast-Intact

Designated Routers

Rendezvous Points

Auto-RP

PIM Bootstrap Router

Reverse-Path Forwarding

Multicast VPN

Multicast VPN Routing and Forwarding

Multicast Distribution Tree Tunnels

BGP Requirements

Multitopology Routing

Multicast Source Discovery Protocol

Multicast Nonstop Forwarding

Multicast Configuration Submodes

Multicast-Routing Configuration Submode

PIM Configuration Submode

IGMP Configuration Submode

MLD Configuration Submode

MSDP Configuration Submode

Understanding Interface Configuration Inheritance

Understanding Interface Configuration Inheritance Disablement

Understanding Enabling and Disabling Interfaces

Multicast Routing Information Base

Multicast Forwarding Information Base

MSDP MD5 Password Authentication

How to Implement Multicast Routing

Configuring PIM-SM and PIM-SSM

PIM-SM Operations

PIM-SSM Operations

Restrictions for PIM-SM and SSM

Configuring a Static RP and Allowing Backward Compatibility

Configuring Auto-RP to Automate Group-to-RP Mappings

Configuring the Bootstrap Router

Calculating Rates per Route

Configuring Multicast Nonstop Forwarding

Prerequisites for Multicast Nonstop Forwarding

Configuring Multicast VPN

Prerequisites for Multicast VPN

Restrictions for Multicast VPN for Multicast Routing

Enabling a VPN for Multicast Routing

Specifying the PIM VRF Instance

Specifying the IGMP VRF Instance

Configuring the MDT Source per VRF

Configuring Multitopology Routing

Restrictions for Configuring Multitopology Routing

Information About Multitopology Routing

Configuring an RPF Topology in PIM

Interconnecting PIM-SM Domains with MSDP

Prerequisites for Interconnecting PIM-SM Domains with MSDP

Controlling Source Information on MSDP Peer Routers

Configuring MSDP MD5 Password Authentication

Multicast only fast reroute (MoFRR)

Feature Overview

Operating Modes of MoFRR

Configuring MoFRR

RIB-based MoFRR

Point-to-Multipoint Traffic Engineering Label-Switched Multicast

Point to Multipoint LSP(P2MP)

Multicast Routing Protocol support for P2MP

Enabling Multicast Forwarding over tunnel interface (at ingress node)

P2MP configurations at egress node and bud node

Configuring Static Reverse Path Forwarding (RPF)

Configuring core tree protocol

Configuration Examples for Implementing Multicast Routing on Cisco IOS XR Software

MSDP Anycast RP Configuration on Cisco IOS XR Software: Example

Bidir-PIM Configuration on Cisco IOS XR Software: Example

Calculating Rates per Route: Example

Preventing Auto-RP Messages from Being Forwarded on Cisco IOS XR Software: Example

Inheritance in MSDP on Cisco IOS XR Software: Example

Configuring IPv4 Multicast VPN: Example

Configuring MVPN to Advertise Routes Between the CE and the PE Using OSPF: Example

Configuring MVPN to Advertise Routes Between the CE and the PE Using BGP: Example

Configuring Multitopology Routing: Example

Additional References

Related Documents

Standards

MIBs

RFCs

Technical Assistance


Implementing Multicast Routing on Cisco IOS XR Software Cisco ASR 9000 Series Routers


Multicast routing is a bandwidth-conserving technology that reduces traffic by simultaneously delivering a single stream of information to potentially thousands of corporate recipients and homes. Applications that take advantage of multicast include video conferencing; corporate communications; distance learning; and distribution of software, stock quotes, and news.

This document assumes that you are familiar with IPv4 and IPv6 multicast routing configuration tasks and concepts for Cisco IOS XR software.

Multicast routing allows a host to send packets to a subset of all hosts as a group transmission rather than to a single host, as in unicast transmission, or to all hosts, as in broadcast transmission. The subset of hosts is known as group members and are identified by a single multicast group address that falls under the IP Class D address range from 224.0.0.0 through 239.255.255.255.

For detailed conceptual information about multicast routing and complete descriptions of the multicast routing commands listed in this module, you can refer to the "Related Documents" section. To locate documentation for other commands that might appear in the course of executing a configuration task, search online in the Cisco IOS XR software master command index.

Feature History for Configuring Multicast Routing on the Cisco CRS-1 Router Software

Release
Modification

Release 2.0

This feature was introduced on the Cisco CRS-1.

Release 3.0

No modification.

Release 3.2

Support was added for the for IPv6 routing protocol on the Cisco CRS-1 and for the bootstrap router (BSR) feature.

Release 3.3.0

No modification.

Release 3.4.0

No modification.

Release 3.5.0

Multicast VPNv4 was supported.

Release 3.6.0

No modification.

Release 3.7.0

The following new features or functionality were added:

Support was added for multitopology routing within a default VRF table.

A new configuration procedure was added for calculating rate per route.

Release 3.8.0

No modification.

Release 3.9.0

Support was added for the following features:

Multicast-only fast reroutes (MoFRR) .

Point-to-multipoint MPLS label-switched multicast routing.


Contents

Prerequisites for Implementing Multicast Routing

Information About Implementing Multicast Routing

How to Implement Multicast Routing

Configuration Examples for Implementing Multicast Routing on Cisco IOS XR Software

Additional References

Prerequisites for Implementing Multicast Routing

The following prerequisites are required to implement multicast routing on your multicast network:

You must install and activate a Package Installation Envelope (PIE) for the multicast routing software. For detailed information about optional PIE installation, see Cisco IOS XR Getting Started Guide.

To perform these configuration tasks, your Cisco IOS XR software system administrator must assign you to a user group associated with a task group that includes the corresponding command task IDs. All command task IDs are listed in individual command references and in the Cisco IOS XR Task ID Reference Guide.

If you need assistance with your task group assignment, contact your system administrator. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of Cisco IOS XR Software System Security Configuration Guide.

You must be familiar with IPv4 and IPv6 multicast routing configuration tasks and concepts.

Unicast routing must be operational.

Information About Implementing Multicast Routing

To implement the multicast routing features described in this document you must understand the following concepts:

Key Protocols and Features Supported in the Cisco IOS XR Software Multicast Routing Implementation

Multicast Routing Functional Overview

Internet Group Management Protocol and Multicast Listener Discovery

Protocol Independent Multicast

PIM Shared Tree and Source Tree (Shortest Path Tree)

Multicast-Intact

Designated Routers

Rendezvous Points

Auto-RP

PIM Bootstrap Router

Reverse-Path Forwarding

Multicast VPN

Multitopology Routing

Multicast Source Discovery Protocol

Multicast Nonstop Forwarding

Multicast Configuration Submodes

Understanding Interface Configuration Inheritance

Understanding Interface Configuration Inheritance Disablement

Understanding Enabling and Disabling Interfaces

Multicast Routing Information Base

MSDP MD5 Password Authentication

Key Protocols and Features Supported in the Cisco IOS XR Software Multicast Routing Implementation

Table 1lists the supported features for IPv4 and IPv6 multicast routing in Cisco IOS XR software

Table 1 Supported Features for IPv4 and IPv6 on the Cisco CRS-1 and Cisco XR 12000 Series Router

Feature
IPv4 Support
IPv6 Support

Dynamic host registration

Yes (IGMP v1/2/3)

Yes (MLD v1/2)

Explicit tracking of hosts, groups, and channels

Yes (IGMP v3)

Yes (MLD v2)

PIM-SM1

Yes

Yes

PIM-SSM2

Yes

Yes

PIM-Bidir3

Yes

No

Auto-RP

Yes

No

Multicast VPN

Yes

Yes4

BSR5

Yes

Yes

MSDP6

Yes

No

BGP7

Yes

Yes

Multicast NSF8

Yes

Yes

OOR handling9

Yes

No

1 Protocol Independent Multicast in sparse mode

2 Protocol Independent Multicast in Source-Specific Multicast

3 Protocol Independent Multicast Bidirectional

4 IPv6 support on Cisco XR 12000 Series Router only

5 PIM bootstrap router

6 Multicast Source Discovery Protocol

7 Multiprotocol Border Gateway Protocol

8 Nonstop forwarding

9 Out of resource


Multicast Routing Functional Overview

Traditional IP communication allows a host to send packets to a single host (unicast transmission) or to all hosts (broadcast transmission). Multicast provides a third scheme, allowing a host to send a single data stream to a subset of all hosts (group transmission) at about the same time. IP hosts 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 IP 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 group 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 and what members it has can vary from group to group and from time to time. A multicast group can be active for a long time, or it may be very short-lived. Membership in a group can change constantly. A group that has members may have no activity.

Routers use the Internet Group Management Protocol (IGMP) (IPv4) and Multicast Listener Discovery (MLD) (IPv6) to learn whether members of a group are present on their directly attached subnets. Hosts join multicast groups by sending IGMP or MLD report messages.

Many multimedia applications involve multiple participants. Multicast is naturally suitable for this communication paradigm.

Cisco IOS XR Multicast Routing Implementation

Cisco IOS XR software supports the following protocols to implement multicast routing:

IGMP and MLD are used (depending on the IP protocol) between hosts on a LAN and the routers on that LAN to track the multicast groups of which hosts are members.

Protocol Independent Multicast in sparse mode (PIM-SM) is used between routers so that they can track which multicast packets to forward to each other and to their directly connected LANs.

Protocol Independent Multicast in Source-Specific Multicast (PIM-SSM) is similar to PIM-SM with the additional ability to report interest in receiving packets from specific source addresses (or from all but the specific source addresses), to an IP multicast address.

PIM-SSM is made possible by IGMPv3 and MLDv2. Hosts can now indicate interest in specific sources using IGMPv3 and MLDv2. SSM does not require a rendezvous point (RP) to operate.

Figure 1 shows IGMP/MLD and PIM-SM operating in a multicast environment.

Figure 1 Multicast Routing Protocols Supported for Cisco IOS XR Software

Internet Group Management Protocol and Multicast Listener Discovery

Cisco IOS XR software provides support for Internet Group Management Protocol (IGMP) over IPv4 and Multicast Listener Discovery (MLD) over IPv6.

IGMP and MLD provide a means for hosts to indicate which multicast traffic they are interested in and for routers to control and limit the flow of multicast traffic throughout the network. Routers build state by means of IGMP and MLD messages; that is, router queries and host reports.

A set of queries and hosts that receive multicast data streams from the same source is called a multicast group. Hosts use IGMP and MLD messages to join and leave multicast groups.


Note IGMP messages use group addresses, which are Class D IP addresses. The high-order four bits of a Class D address are 1110. Host group addresses can be in the range 224.0.0.0 to 239.255.255.255. The address 224.0.0.0 is guaranteed not to be assigned to any group. The address 224.0.0.1 is assigned to all systems on a subnet. The address 224.0.0.2 is assigned to all routers on a subnet.


IGMP and MLD Versions

The following points describe IGMP versions 1, 2, and 3:

IGMP Version 1 provides for the basic query-response mechanism that allows the multicast router to determine which multicast groups are active and for other processes that enable hosts to join and leave a multicast group.

IGMP Version 2 extends IGMP allowing such features as the IGMP query timeout and the maximum query-response time. See RFC 2236.


Note MLDv1 provides the same functionality (under IPv6) as IGMP Version 2.


IGMP Version 3 permits joins and leaves for certain source and group pairs instead of requesting traffic from all sources in the multicast group.


Note MLDv2 provides the same functionality (under IPv6) as IGMP Version 3.


IGMP Routing Example

Figure 2 illustrates two sources, 10.0.0.1 and 10.0.1.1, that are multicasting to group 239.1.1.1. The receiver wants to receive traffic addressed to group 239.1.1.1 from source 10.0.0.1 but not from source 10.0.1.1. The host must send an IGMPv3 message containing a list of sources and groups (S, G) that it wants to join and a list of sources and groups (S, G) that it wants to leave. Router C can now use this information to prune traffic from Source 10.0.1.1 so that only Source 10.0.0.1 traffic is being delivered to
Router C.

Figure 2 IGMPv3 Signaling


Note When configuring IGMP, ensure that all systems on the subnet support the same IGMP version. The router does not automatically detect Version 1 systems. Configure the router for Version 2 if your hosts do not support Version 3.


Protocol Independent Multicast

Protocol Independent Multicast (PIM) is a routing protocol designed to send and receive multicast routing updates. Proper operation of multicast depends on knowing the unicast paths towards a source or an RP. PIM relies on unicast routing protocols to derive this reverse-path forwarding (RPF) information. As the name PIM implies, it functions independently of the unicast protocols being used. PIM relies on the Routing Information Base (RIB) for RPF information. If the multicast subsequent address family identifier (SAFI) is configured for Border Gateway Protocol (BGP), or if multicast intact is configured, a separate multicast unicast RIB is created and populated with the BGP multicast SAFI routes, the intact information, and any IGP information in the unicast RIB. Otherwise, PIM gets information directly from the unicast SAFI RIB. Both multicast unicast and unicast databases are outside of the scope of PIM.

The Cisco IOS XR implementation of PIM is based on RFC 4601 Protocol Independent Multicast - Sparse Mode (PIM-SM): Protocol Specification. For more information, see RFC 4601 and the Protocol Independent Multicast (PIM): Motivation and Architecture Internet Engineering Task Force (IETF) Internet draft.


Note Cisco IOS XR software supports PIM-SM, PIM-SSM, PIM Bidir, and PIM Version 2 only. PIM Version 1 hello messages that arrive from neighbors are rejected.


PIM-Sparse Mode

Typically, PIM in sparse mode (PIM-SM) operation is used in a multicast network when relatively few routers are involved in each multicast. Routers do not forward multicast packets for a group, unless there is an explicit request for traffic. Requests are accomplished using PIM join messages, which are sent hop by hop toward the root node of the tree. The root node of a tree in PIM-SM is the rendezvous point (RP) in the case of a shared tree or the first-hop router that is directly connected to the multicast source in the case of a shortest path tree (SPT). The RP keeps track of multicast groups, and the sources that send multicast packets are registered with the RP by the first-hop router of the source.

As a PIM join travels up the tree, routers along the path set up the multicast forwarding state so that the requested multicast traffic is forwarded back down the tree. When multicast traffic is no longer needed, a router sends a PIM prune message up the tree toward the root node to prune (or remove) the unnecessary traffic. As this PIM prune travels hop by hop up the tree, each router updates its forwarding state appropriately. Ultimately, the forwarding state associated with a multicast group or source is removed. Additionally, if prunes are not explicitly sent, the PIM state will timeout and be removed in the absence of any further join messages.

PIM-SM is the best choice for multicast networks that have potential members at the end of WAN links.

PIM-Source Specific Multicast

In many multicast deployments where the source is known, protocol-independent multicast-source-specific multicast (PIM-SSM) mapping is the obvious multicast routing protocol choice to use because of its simplicity. Typical multicast deployments that benefit from PIM-SSM consist of entertainment-type solutions like the ETTH space, or financial deployments that completely rely on static forwarding.

PIM-SSM is derived from PIM-SM. However, whereas PIM-SM allows for the data transmission of all sources sending to a particular group in response to PIM join messages, the SSM feature forwards traffic to receivers only from those sources that the receivers have explicitly joined. Because PIM joins and prunes are sent directly towards the source sending traffic, an RP and shared trees are unnecessary and are disallowed. SSM is used to optimize bandwidth utilization and deny unwanted Internet broadcast traffic. The source is provided by interested receivers through IGMPv3 membership reports.

In SSM, delivery of datagrams is based on (S,G) channels. Traffic for one (S,G) channel consists of datagrams with an IP unicast source address S and the multicast group address G as the IP destination address. Systems receive traffic by becoming members of the (S,G) channel. Signaling is not required, but receivers must subscribe or unsubscribe to (S,G) channels to receive or not receive traffic from specific sources. Channel subscription signaling uses IGMP to include mode membership reports, which are supported only in Version 3 of IGMP (IGMPv3).

To run SSM with IGMPv3, SSM must be supported on the multicast router, the host where the application is running, and the application itself. Cisco IOS XR software allows SSM configuration for an arbitrary subset of the IP multicast address range 224.0.0.0 through 239.255.255.255. When an SSM range is defined, existing IP multicast receiver applications do not receive any traffic when they try to use addresses in the SSM range, unless the application is modified to use explicit (S,G) channel subscription.

PIM Shared Tree and Source Tree (Shortest Path Tree)

In PIM-SM, the rendezvous point (RP) is used to bridge sources sending data to a particular group with receivers sending joins for that group. In the initial setup of state, interested receivers receive data from senders to the group across a single data distribution tree rooted at the RP. This type of distribution tree is called a shared tree or rendezvous point tree (RPT) as illustrated in Figure 3. Data from senders is delivered to the RP for distribution to group members joined to the shared tree.

Figure 3 Shared Tree and Source Tree (Shortest Path Tree)

Unless the spt-threshold infinity command is configured, this initial state gives way as soon as traffic is received on the leaf routers (designated router closest to the host receivers). When the leaf router receives traffic from the RP on the RPT, the router initiates a switch to a data distribution tree rooted at the source sending traffic. This type of distribution tree is called a shortest path tree or source tree. By default, the Cisco IOS XR software switches to a source tree when it receives the first data packet from a source.

The following process describes the move from shared tree to source tree in more detail:

1. Receiver joins a group; leaf Router C sends a join message toward RP.

2. RP puts link to Router C in its outgoing interface list.

3. Source sends data; Router A encapsulates data in Register and sends it to RP.

4. RP forwards data down the shared tree to Router C and sends a join message toward Source. At this point, data may arrive twice at the RP, once encapsulated and once natively.

5. When data arrives natively (unencapsulated) at RP, RP sends a register-stop message to Router A.

6. By default, receipt of the first data packet prompts Router C to send a join message toward Source.

7. When Router C receives data on (S,G), it sends a prune message for Source up the shared tree.

8. RP deletes the link to Router C from outgoing interface of (S,G). RP triggers a prune message toward Source.

Join and prune messages are sent for sources and RPs. They are sent hop by hop and are processed by each PIM router along the path to the source or RP. Register and register-stop messages are not sent hop by hop. They are exchanged using direct unicast communication between the designated router that is directly connected to a source and the RP for the group.


Tip The spt-threshold infinity command lets you configure the router so that it never switches to the shortest path tree (SPT).


Multicast-Intact

The multicast-intact feature provides the ability to run multicast routing (PIM) when Interior Gateway Protocol (IGP) shortcuts are configured and active on the router. Both Open Shortest Path First, version 2 (OSPFv2), and Intermediate System-to-Intermediate System (IS-IS) support the multicast-intact feature. Multiprotocol Label Switching Traffic Engineering (MPLS-TE) and IP multicast coexistence is supported in Cisco IOS XR software by using the mpls traffic-eng multicast-intact IS-IS or OSPF router command. See Cisco IOS XR Routing Configuration Guide for the Cisco CRS-1 Router for information on configuring multicast intact using IS-IS and OSPF commands.

You can enable multicast-intact in the IGP when multicast routing protocols (PIM) are configured and IGP shortcuts are configured on the router. IGP shortcuts are MPLS tunnels that are exposed to IGP. The IGPs route the IP traffic over these tunnels to destinations that are downstream from the egress router of the tunnel (from an SPF perspective). PIM cannot use IGP shortcuts for propagating PIM joins because reverse path forwarding (RPF) cannot work across a unidirectional tunnel.

When you enable multicast-intact on an IGP, the IGP publishes a parallel or alternate set of equal-cost next-hops for use by PIM. These next-hops are called mcast-intact next-hops. The mcast-intact next-hops have the following attributes:

They are guaranteed not to contain any IGP shortcuts.

They are not used for unicast routing but are used only by PIM to look up an IPv4 next hop to a PIM source.

They are not published to the Forwarding Information Base (FIB).

When multicast-intact is enabled on an IGP, all IPv4 destinations that were learned through link-state advertisements are published with a set equal-cost mcast-intact next-hops to the RIB. This attribute applies even when the native next-hops have no IGP shortcuts.

In IS-IS, the max-paths limit is applied by counting both the native and mcast-intact next-hops together. (In OSPFv2, the behavior is slightly different.)

Designated Routers

Cisco routers use PIM-SM to forward multicast traffic and follow an election process to select a designated router (DR) when there is more than one router on a LAN segment.

The designated router is responsible for sending PIM register and PIM join and prune messages toward the RP to inform it about host group membership.

If there are multiple PIM-SM routers on a LAN, a designated router must be elected to avoid duplicating multicast traffic for connected hosts. The PIM router with the highest IP address becomes the DR for the LAN unless you choose to force the DR election by use of the dr-priority command. The DR priority option allows you to specify the DR priority of each router on the LAN segment (default priority = 1) so that the router with the highest priority is elected as the DR. If all routers on the LAN segment have the same priority, the highest IP address is again used as the tiebreaker.

Figure 4 illustrates what happens on a multiaccess segment. Router A (10.0.0.253) and Router B (10.0.0.251) are connected to a common multiaccess Ethernet segment with Host A (10.0.0.1) as an active receiver for Group A. As the Explicit Join model is used, only Router A, operating as the DR, sends joins to the RP to construct the shared tree for Group A. If Router B were also permitted to send (*, G) joins to the RP, parallel paths would be created and Host A would receive duplicate multicast traffic. When Host A begins to source multicast traffic to the group, the DR's responsibility is to send register messages to the RP. Again, if both routers were assigned the responsibility, the RP would receive duplicate multicast packets.

If the DR fails, the PIM-SM provides a way to detect the failure of Router A and to elect a failover DR. If the DR (Router A) were to become inoperable, Router B would detect this situation when its neighbor adjacency with Router A timed out. Because Router B has been hearing IGMP membership reports from Host A, it already has IGMP state for Group A on this interface and immediately sends a join to the RP when it becomes the new DR. This step reestablishes traffic flow down a new branch of the shared tree using Router B. Additionally, if Host A were sourcing traffic, Router B would initiate a new register process immediately after receiving the next multicast packet from Host A. This action would trigger the RP to join the SPT to Host A, using a new branch through Router B.


Tip Two PIM routers are neighbors if there is a direct connection between them. To display your PIM neighbors, use the show pim neighbor command in EXEC mode.


Figure 4 Designated Router Election on a Multiaccess Segment


Note DR election process is required only on multiaccess LANs. The last-hop router directly connected to the host is the DR.


Rendezvous Points

When PIM is configured in sparse mode, you must choose one or more routers to operate as a rendezvous point (RP). A rendezvous point is a single common root placed at a chosen point of a shared distribution tree, as illustrated in Figure 3. A rendezvous point can be either configured statically in each box or learned through a dynamic mechanism.

PIM DRs forward data from directly connected multicast sources to the rendezvous point for distribution down the shared tree. Data is forwarded to the rendezvous point in one of two ways:

Encapsulated in register packets and unicast directly to the rendezvous point by the first-hop router operating as the DR.

Multicast forwarded by the RPF forwarding algorithm, described in the "Reverse-Path Forwarding" section, if the rendezvous point has itself joined the source tree.

The rendezvous point address is used by first-hop routers to send PIM register messages on behalf of a host sending a packet to the group. The rendezvous point address is also used by last-hop routers to send PIM join and prune messages to the rendezvous point to inform it about group membership. You must configure the rendezvous point address on all routers (including the rendezvous point router).

A PIM router can be a rendezvous point for more than one group. Only one rendezvous point address can be used at a time within a PIM domain. The conditions specified by the access list determine for which groups the router is a rendezvous point.

You can either manually configure a PIM router to function as a rendezvous point or allow the rendezvous point to learn group-to-RP mappings automatically by configuring Auto-RP or BSR. (For more information, see the "Auto-RP" section that follows and "PIM Bootstrap Router" section.)

Auto-RP

Automatic route processing (Auto-RP) is a feature that automates the distribution of group-to-RP mappings in a PIM network. This feature has the following benefits:

It is easy to use multiple RPs within a network to serve different group ranges.

It allows load splitting among different RPs and arrangement of RPs according to the location of group participants.

It avoids inconsistent, manual RP configurations that can cause connectivity problems.

Multiple RPs can be used to serve different group ranges or to serve as hot backups of each other. To ensure that Auto-RP functions, configure routers as candidate RPs so that they can announce their interest in operating as the RP for certain group ranges. Additionally, a router must be designated as an RP-mapping agent that receives the RP-announcement messages from the candidate RPs and arbitrates conflicts. The RP-mapping agent sends the consistent group-to-RP mappings to all remaining routers. Thus, all routers automatically discover which RP to use for the groups they support.


Tip By default, if a given group address is covered by group-to-RP mappings from both static RP configuration and is discovered using Auto-RP or PIM BSR, the Auto-RP or PIM BSR range is preferred. To override the default to use RP mapping only, use the rp-address override keyword.



Note If you configure PIM in sparse mode and do not configure Auto-RP, you must statically configure an RP as described in the "Configuring a Static RP and Allowing Backward Compatibility" section.

When router interfaces are configured in sparse mode, Auto-RP can still be used if all routers are configured with a static RP address for the Auto-RP groups.



Note Auto-RP is supported in the IPv4 address family only.


PIM Bootstrap Router

The PIM bootstrap router (BSR) provides a fault-tolerant, automated RP discovery and distribution mechanism that simplifies the Auto-RP process. This feature is enabled by default allowing routers to dynamically learn the group-to-RP mappings.

PIM uses the BSR to discover and announce RP-set information for each group prefix to all the routers in a PIM domain. This is the same function accomplished by Auto-RP, but the BSR is part of the PIM Version 2 specification. The BSR mechanism interoperates with Auto-RP on Cisco routers.

To avoid a single point of failure, you can configure several candidate BSRs in a PIM domain. A BSR is elected among the candidate BSRs automatically. Candidates use bootstrap messages to discover which BSR has the highest priority. The candidate with the highest priority sends an announcement to all PIM routers in the PIM domain that it is the BSR.

Routers that are configured as candidate RPs unicast to the BSR the group range for which they are responsible. The BSR includes this information in its bootstrap messages and disseminates it to all PIM routers in the domain. Based on this information, all routers are able to map multicast groups to specific RPs. As long as a router is receiving the bootstrap message, it has a current RP map.

Reverse-Path Forwarding

Reverse-path forwarding (RPF) is an algorithm used for forwarding multicast datagrams. It functions as follows:

If a router receives a datagram on an interface it uses to send unicast packets to the source, the packet has arrived on the RPF interface.

If the packet arrives on the RPF interface, a router forwards the packet out the interfaces present in the outgoing interface list of a multicast routing table entry.

If the packet does not arrive on the RPF interface, the packet is silently discarded to prevent loops.

PIM uses both source trees and RP-rooted shared trees to forward datagrams; the RPF check is performed differently for each, as follows:

If a PIM router has an (S,G) entry present in the multicast routing table (a source-tree state), the router performs the RPF check against the IP address of the source for the multicast packet.

If a PIM router has no explicit source-tree state, this is considered a shared-tree state. The router performs the RPF check on the address of the RP, which is known when members join the group.

Sparse-mode PIM uses the RPF lookup function to determine where it needs to send joins and prunes. (S,G) joins (which are source-tree states) are sent toward the source. (*,G) joins (which are shared-tree states) are sent toward the RP.

Multicast VPN

To be able to offer Layer 3 multicast services to customers with multiple distributed sites, service providers are looking for a secure and scalable mechanism to transmit customer multicast traffic across the provider network. Multicast VPN (MVPN) provides such services over a shared service provider backbone using native multicast technology similar to BGP/MPLS VPN.

MVPN emulates MPLS VPN technology in its adoption of the multicast domain (MD) concept, in which provider edge (PE) routers establish virtual PIM neighbor connections with other PE routers connected to the same customer VPN. These PE routers thereby form a secure, virtual multicast domain over the provider network. Multicast traffic is then transmitted across the core network from one site to another as if the traffic were going through a dedicated provider network.

Separate multicast routing and forwarding tables are maintained for each individual VPN routing and forwarding (VRF) instance, with traffic being sent through VPN tunnels across the service provider backbone.

Multicast VPN Routing and Forwarding

Dedicated multicast routing and forwarding tables are created for each VPN to separate traffic in one VPN from another.

The VPN-specific multicast routing and forwarding database is referred to as MVRF. On a PE router, an MVRF is created when multicast is enabled for a VRF. Protocol Independent Multicast (PIM), and Internet Group Management Protocol (IGMP) protocols run in the context of MVRF, and all routes created by an MVRF protocol instance are associated with the corresponding MVRF. In addition to VRFs, which hold VPN-specific protocol states, a PE router always has a global VRF instance, containing all the routing and forwarding information for the provider network.

Multicast Distribution Tree Tunnels

The multicast distribution tree (MDT) can span multiple customer sites and the provider network, allowing traffic to flow from one source to multiple receivers.

Secure data transmission is achieved by encapsulating multicast packets in a provider header from the sending customer edge (CE) router at the ingress PE router and transmitting the packets across the core. At the egress PE router, the encapsulated packets are decapsulated then sent to the CE receiving routers.

Multicast distribution tree (MDT) tunnels are point-to-multipoint. Packets sent to an MDT tunnel interface are received by multiple receiving routers. Packets sent to an MDT tunnel interface are encapsulated, and packets received from a MDT tunnel interface are decapsulated. Figure 5 shows a virtual peer connection between two PE routers over an MDT tunnel interface.

Figure 5 Virtual PIM Peer Connection over an MDT Tunnel Interface

Encapsulating multicast packets in a provider header allows PE routers to be unaware of the packet origin—all VPN packets passing through the provider network are viewed as native multicast packets and are routed based on the routing information in the core network. PE routers only need to support native multicast routing to support MVPN.

MVPN also supports optimized VPN traffic forwarding for high-bandwidth applications that have sparsely distributed receivers. A dedicated multicast group can be used to encapsulate packets from a specific source, and an optimized MDT can be created to send traffic only to PE routers with interested receivers. This is referred to as data MDT.

BGP Requirements

PE routers are the only routers that need to be MVPN-aware and able to signal remote PEs with information regarding the MVPN. It is fundamental that all PE routers have a BGP relationship with each other, either directly or through a route reflector, because the PE routers use the BGP peering address information to derive the RPF PE peer within a given VRF.

PIM-SSM MDT tunnels cannot be set up without a configured BGP MDT address-family, because you establish the tunnels, using the BGP connector attribute.

See the Implementing BGP on Cisco IOS XR Software module of the Cisco IOS XR Routing Configuration Guide for information on BGP support for Multicast VPN.

Multitopology Routing

Multitopology routing allows you to manipulate network traffic flow when desirable (for example, to broadcast duplicate video streams) to flow over non-overlapping paths.

At the core of multitopology routing technology is router space infrastructure (RSI). RSI manages the global configuration of routing tables. These tables are hierarchically organized into VRF tables under logical routers. By default, RSI creates tables for unicast and multicast for both IPv4 and IPv6 under the default VRF. Using multitopology routing, you can configure named topologies for the default VRF.

PIM uses a routing policy that supports matching on source or group address to select the topology in which to look up the reverse-path forwarding (RPF) path to the source. If you do not configure a policy, the existing behavior (to select a default table) remains in force.

Currently, IS-IS and PIM routing protocols alone support multitopology-enabled network.

For information on how to configure multitopology routing, see Configuring Multitopology Routing.

Multicast Source Discovery Protocol

Multicast Source Discovery Protocol (MSDP) is a mechanism to connect multiple PIM sparse-mode domains. MSDP allows multicast sources for a group to be known to all rendezvous points (RPs) in different domains. Each PIM-SM domain uses its own RPs and need not depend on RPs in other domains.

An RP in a PIM-SM domain has MSDP peering relationships with MSDP-enabled routers in other domains. Each peering relationship occurs over a TCP connection, which is maintained by the underlying routing system.

MSDP speakers exchange messages called Source Active (SA) messages. When an RP learns about a local active source, typically through a PIM register message, the MSDP process encapsulates the register in an SA message and forwards the information to its peers. The message contains the source and group information for the multicast flow, as well as any encapsulated data. If a neighboring RP has local joiners for the multicast group, the RP installs the S, G route, forwards the encapsulated data contained in the SA message, and sends PIM joins back towards the source. This process describes how a multicast path can be built between domains.


Note Although you should configure BGP or Multiprotocol BGP for optimal MSDP interdomain operation, this is not considered necessary in the Cisco IOS XR software implementation. For information about how BGP or Multiprotocol BGP may be used with MSDP, see the MSDP RPF rules listed in the Multicast Source Discovery Protocol (MSDP), Internet Engineering Task Force (IETF) Internet draft.


Multicast Nonstop Forwarding

The Cisco IOS XR nonstop forwarding (NSF) feature for multicast enhances high availability (HA) of multicast packet forwarding. NSF prevents hardware or software failures on the control plane from disrupting the forwarding of existing packet flows through the router.

How does multicast NSF work? The contents of the Multicast Forwarding Information Base (MFIB) are frozen during a control plane failure. Subsequently, PIM attempts to recover normal protocol processing and state before the neighboring routers time out the PIM hello neighbor adjacency for the problematic router. This behavior prevents the NSF-capable router from being transferred to neighbors that will otherwise detect the failure through the timed-out adjacency. Routes in MFIB are marked as stale after entering NSF, and traffic continues to be forwarded (based on those routes) until NSF completion. On completion, MRIB notifies MFIB and MFIB performs a mark-and-sweep to synchronize MFIB with the current MRIB route info.


Note Nonstop forwarding is not supported for PIM bidirectional routes. If a PIM or MRIB failure (including RP failover) happens with multicast-routing NSF enabled, PIM bidirectional routes in the MFIBs are purged immediately and forwarding on these routes stops. Routes are reinstalled and forwarding recommences after NSF recovery has ended. This affects only bidirectional routes. PIM-SM and PIM-SSM routes are forwarded with NSF during the failure. This exception is designed to prevent possible multicast routing loops from forming when the control plane is not able to participate in the BiDir Designated Forwarder election.


Multicast Configuration Submodes

Cisco IOS XR software moves control plane CLI configurations to protocol-specific submodes to provide mechanisms for enabling, disabling, and configuring multicast features on a large number of interfaces.

Cisco IOS XR software allows you to issue most commands available under submodes as one single command string from global configuration mode.

For example, the ssm command could be executed from the multicast-routing configuration submode like this:

RP/0/RP0/CPU0:router(config)# multicast-routing
RP/0/RP0/CPU0:router(config-mcast-ipv4)# ssm range
 
   

Alternatively, you could issue the same command from global configuration mode like this:

RP/0/RP0/CPU0:router(config)# multicast-routing ssm range
 
   

The following multicast protocol-specific submodes are available through these configuration submodes:

Multicast-Routing Configuration Submode

PIM Configuration Submode

IGMP Configuration Submode

MLD Configuration Submode

MSDP Configuration Submode

Multicast-Routing Configuration Submode

When you issue the multicast-routing ipv4 or multicast-routing ipv6 command, all default multicast components (PIM, IGMP, MLD, MFWD, and MRIB) are automatically started, and the CLI prompt changes to "config-mcast-ipv4" or "config-mcast-ipv6", indicating that you have entered multicast-routing configuration submode.

PIM Configuration Submode

When you issue the router pim command, the CLI prompt changes to "config-pim-ipv4," indicating that you have entered the default pim address-family configuration submode. To enter pim address-family configuration submode for IPv6, type the address-family ipv6 keyword together with the router pim command before pressing Enter.

IGMP Configuration Submode

When you issue the router igmp command, the CLI prompt changes to "config-igmp," indicating that you have entered IGMP configuration submode.

MLD Configuration Submode

When you issue the router mld command, the CLI prompt changes to "config-mld," indicating that you have entered MLD configuration submode.

MSDP Configuration Submode

When you issue the router msdp command, the CLI prompt changes to "config-msdp," indicating that you have entered router MSDP configuration submode.

Understanding Interface Configuration Inheritance

Cisco IOS XR software allows you to configure commands for a large number of interfaces by applying command configuration within a multicast routing submode that could be inherited by all interfaces. To override the inheritance mechanism, you can enter interface configuration submode and explicitly enter a different command parameter.

For example, in the following configuration you could quickly specify (under router PIM configuration mode) that all existing and new PIM interfaces on your router will use the hello interval parameter of 420 seconds. However, Packet-over-SONET/SDH (POS) interface 0/1/0/1 overrides the global interface configuration and uses the hello interval time of 210 seconds.

RP/0/RP0/CPU0:router(config)# router pim
RP/0/RP0/CPU0:router(config-pim-default-ipv4)# hello-interval 420
RP/0/RP0/CPU0:router(config-pim-default-ipv4)# interface pos 0/1/0/1
RP/0/RP0/CPU0:router(config-pim-ipv4-if)# hello-interval 210
 
   

The following is a listing of commands (specified under the appropriate router submode) that use the inheritance mechanism:

router pim
  dr-priority
  hello-interval
  join-prune-interval
 
   
multicast-routing
  version
  query-interval
  query-max-response-time
  explicit-tracking
router mld
  interface all disable
  version
  query-interval
  query-max-response-time
  explicit-tracking
 
   
router msdp
  connect-source
  sa-filter
  filter-sa-request list
  remote-as
  ttl-threshold

Understanding Interface Configuration Inheritance Disablement

As stated elsewhere, Cisco IOS XR software allows you to configure multiple interfaces by applying configurations within a multicast routing submode that can be inherited by all interfaces.

To override the inheritance feature on specific interfaces or on all interfaces, you can enter the address-family IPv4 or IPv6 submode of multicast routing configuration mode, and enter the interface-inheritance disable command together with the interface type interface-path-id or interface all command. This causes PIM or IGMP protocols to disallow multicast routing and to allow only multicast forwarding on those interfaces specified. However, routing can still be explicitly enabled on specified individual interfaces.

The following configuration disables multicast routing interface inheritance under PIM and IGMP generally, although forwarding enablement continues. The example shows interface enablement under IGMP of GigabitEthernet 0/6/0/3:

RP/0/RP0/CPU0:router# multicast-routing address-family ipv4
RP/0/RP0/CPU0:router(config-mcast-default-ipv4)# interface all enable
RP/0/RP0/CPU0:router(config-mcast-default-ipv4)# interface-inheritance disable
!
!
RP/0/RP0/CPU0:router(config)# router igmp
RP/0/RP0/CPU0:router(config-igmp)# vrf default
RP/0/RP0/CPU0:router(config-igmp)# interface GigabitEthernet0/6/0/0
RP/0/RP0/CPU0:router(config-igmp-name-if)# router enable

For related information, see "Understanding Enabling and Disabling Interfaces"

Understanding Enabling and Disabling Interfaces

When the Cisco IOS XR multicast routing feature is configured on your router, by default, no interfaces are enabled.

To enable multicast routing and protocols on a single interface or multiple interfaces, you must explicitly enable interfaces using the interface command in multicast routing configuration mode.

To set up multicast routing on all interfaces, enter the interface all command in multicast routing configuration mode. For any interface to be fully enabled for multicast routing, it must be enabled specifically (or be default) in multicast routing configuration mode, and it must not be disabled in the PIM and IGMP/MLD configuration modes.

For example, in the following configuration, all interfaces are explicitly configured from multicast routing configuration submode:

RP/0/RP0/CPU0:router(config)# multicast-routing
RP/0/RP0/CPU0:router(config-mcast)# interface all enable

To disable an interface that was globally configured from the multicast routing configuration submode, enter interface configuration submode, as illustrated in the following example:

RP/0/RP0/CPU0:router(config-mcast)# interface pos 0/1/0/0
RP/0/RP0/CPU0:router(config-mcast-default-ipv4-if)# disable

Multicast Routing Information Base

The Multicast Routing Information Base (MRIB) is a protocol-independent multicast routing table that describes a logical network in which one or more multicast routing protocols are running. The tables contain generic multicast routes installed by individual multicast routing protocols. There is an MRIB for every logical network (VPN) in which the router is configured. MRIBs do not redistribute routes among multicast routing protocols; they select the preferred multicast route from comparable ones, and they notify their clients of changes in selected attributes of any multicast route.

Multicast Forwarding Information Base

Multicast Forwarding Information Base (MFIB) is a protocol-independent multicast forwarding system that contains unique multicast forwarding entries for each source or group pair known in a given network. There is a separate MFIB for every logical network (VPN) in which the router is configured. Each MFIB entry resolves a given source or group pair to an incoming interface (IIF) for reverse forwarding (RPF) checking and an outgoing interface list (olist) for multicast forwarding.

MSDP MD5 Password Authentication

MSDP MD5 password authentication is an enhancement to support Message Digest 5 (MD5) signature protection on a TCP connection between two Multicast Source Discovery Protocol (MSDP) peers. This feature provides added security by protecting MSDP against the threat of spoofed TCP segments being introduced into the TCP connection stream.

MSDP MD5 password authentication verifies each segment sent on the TCP connection between MSDP peers. The password command is used to enable MD5 authentication for TCP connections between two MSDP peers. When MD5 authentication is enabled between two MSDP peers, each segment sent on the TCP connection between the peers is verified.


Note MD5 authentication must be configured with the same password on both MSDP peers; otherwise, the connection between them will not be made.


MSDP MD5 password authentication uses an industry-standard MD5 algorithm for improved reliability and security.

How to Implement Multicast Routing

This section contains instructions for both building a basic multicast configuration, as well as optional tasks to help you to optimize, debug, and discover the routers in your multicast network.

Configuring PIM-SM and PIM-SSM (required)

Configuring a Static RP and Allowing Backward Compatibility (required)

Configuring Auto-RP to Automate Group-to-RP Mappings (optional)

Configuring the Bootstrap Router (optional)

Calculating Rates per Route (optional)

Configuring Multicast Nonstop Forwarding (optional)

Configuring Multicast VPN (optional)

Configuring Multitopology Routing (optional)

Interconnecting PIM-SM Domains with MSDP (optional)

Controlling Source Information on MSDP Peer Routers (optional)

Configuring MSDP MD5 Password Authentication (optional)

Configuring PIM-SM and PIM-SSM

PIM is an efficient IP routing protocol that is "independent" of a routing table, unlike other multicast protocols such as Multicast Open Shortest Path First (MOSPF) or Distance Vector Multicast Routing Protocol (DVMRP).

Cisco IOS XR software supports Protocol Independent Multicast in sparse mode (PIM-SM) and Protocol Independent Multicast in Source-Specific Multicast (PIM-SSM), permitting both to operate on your router at the same time.

PIM-SM Operations

PIM in sparse mode operation is used in a multicast network when relatively few routers are involved in each multicast and these routers do not forward multicast packets for a group, unless there is an explicit request for the traffic.

For more information about PIM-SM, see the "PIM-Sparse Mode" section.

PIM-SSM Operations

PIM in Source-Specific Multicast operation uses information found on source addresses for a multicast group provided by receivers and performs source filtering on traffic.

By default, PIM-SSM operates in the 232.0.0.0/8 multicast group range for IPv4 and ff3x::/32 (where x is any valid scope) in IPv6. To configure these values, use the ssm range command.

If SSM is deployed in a network already configured for PIM-SM, only the last-hop routers must be upgraded with Cisco IOS XR software that supports the SSM feature.

No MSDP SA messages within the SSM range are accepted, generated, or forwarded.

For more information about PIM-SSM, see the "PIM-Source Specific Multicast" section.

Restrictions for PIM-SM and SSM

Interoperability with SSM

PIM-SM operations within the SSM range of addresses change to PIM-SSM. In this mode, only PIM (S,G) join and prune messages are generated by the router, and no (S,G) RP shared tree or (*,G) shared tree messages are generated.

IGMP Version

To report multicast memberships to neighboring multicast routers, hosts use IGMP and all routers on the subnet must be configured with the same version of IGMP.

A router running Cisco IOS XR software does not automatically detect Version 1 systems. You must use the version command in router IGMP configuration submode to configure the IGMP version.

MLD Version

To report multicast memberships to neighboring multicast routers, routers use MLD, and all routers on the subnet must be configured with the same version of MLD.

SUMMARY STEPS

1. configure

2. multicast-routing [address-family {ipv4 | ipv6}]

3. interface all enable

4. exit

5. router {igmp | mld}

6. version {1 | 2 | 3}

7. end
or
commit

8. show pim [ipv4 | ipv6] group-map [ip-address-name] [info-source]

9. show pim [vrf vrf-name] [ipv4 | ipv6] topology [source-ip-address [group-ip-address] | entry-flag flag | interface-flag | summary] [route-count]

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

configure

Example:

RP/0/RP0/CPU0:router# configure

Enters global configuration mode.

Step 2 

multicast-routing [address-family {ipv4 | ipv6}]

Example:

RP/0/RP0/CPU0:router(config)# multicast-routing

Enters multicast routing configuration mode.

The following multicast processes are started: MRIB, MFWD, PIM, IGMP, and MLD.

For IPv4, IGMP version 3 is enabled by default; for IPv6, MLD version 1 is enabled by default.

Step 3 

interface all enable

Example:

RP/0/RP0/CPU0:router(config-mcast-ipv4)# interface all enable

Enables multicast routing and forwarding on all new and existing interfaces.

Step 4 

exit

Example:

RP/0/RP0/CPU0:router(config-mcast-ipv4)# exit

Exits multicast routing configuration mode, and returns the router to the source configuration mode.

Step 5 

router {igmp | mld}

Example:
RP/0/RP0/CPU0:router(config)# router igmp 

(Optional) Enters router IGMP or MLD configuration mode.

Step 6 

version {1 | 2 | 3}

Example:

RP/0/RP0/CPU0:router(config-igmp)# version 3

(Optional) Selects the IGMP or MLD version that the router interface uses.

The default for IGMP is version 3; the default for MLD is version 1.

Host receivers must support IGMPv3 for PIM-SSM operation.

If this command is configured in router IGMP or router MLD configuration mode, parameters are inherited by all new and existing interfaces. You can override these parameters on individual interfaces from interface configuration mode.

Step 7 

end
or

commit

Example:

RP/0/RP0/CPU0:router(config-igmp)# end

or

RP/0/RP0/CPU0:router(config-igmp)# commit

Saves configuration changes.

When you issue the end command, the system prompts you to commit changes:

Uncommitted changes found, commit them 
before exiting(yes/no/cancel)? 
[cancel]:
 
        

Entering yes saves configuration changes to the running configuration file, exits the configuration session, and returns the router to EXEC mode.

Entering no exits the configuration session and returns the router to EXEC mode without committing the configuration changes.

Entering cancel leaves the router in the current configuration session without exiting or committing the configuration changes.

Use the commit command to save the configuration changes to the running configuration file and remain within the configuration session.

Step 8 

show pim [ipv4 | ipv6] group-map [ip-address-name] [info-source]

Example:

RP/0/RP0/CPU0:router# show pim ipv4 group-map

(Optional) Displays group-to-PIM mode mapping.

Step 9 

show pim [vrf vrf-name] [ipv4 | ipv6] topology [source-ip-address [group-ip-address] | entry-flag flag | interface-flag | summary] [route-count]

Example:

RP/0/RP0/CPU0:router# show pim topology

(Optional) Displays PIM topology table information for a specific group or all groups.

Configuring a Static RP and Allowing Backward Compatibility

When PIM is configured in sparse mode, you must choose one or more routers to operate as a rendezvous point (RP) for a multicast group. An RP is a single common root placed at a chosen point of a shared distribution tree. An RP can either be configured statically in each router, or learned through Auto-RP or BSR.

This task configures a static RP. For more information about RPs, see the "Rendezvous Points" section. For configuration information for Auto-RP, see the "Configuring Auto-RP to Automate Group-to-RP Mappings" section.

SUMMARY STEPS

1. configure

2. router pim [address-family {ipv4 | ipv6}]

3. rp-address ip-address [group-access-list] [bidir] [override]

4. old-register-checksum

5. exit

6. {ipv4 | ipv6} access-list name

7. [sequence-number] permit source [source-wildcard]

8. end
or
commit

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

configure

Example:

RP/0/RP0/CPU0:router# configure

Enters global configuration mode.

Step 2 

router pim [address-family {ipv4 | ipv6}]

Example:

RP/0/RP0/CPU0:router(config)# router pim

Enters PIM configuration mode, or PIM address-family configuration submode.

Step 3 

rp-address ip-address [group-access-list] [bidir] [override]

Example:

RP/0/RP0/CPU0:router(config-pim-default-ipv4)# rp-address 172.16.6.22 rp-access

Assigns an RP to multicast groups.

If you specify a group-access-list-number value, you must configure that access list using the ipv4 access-list command.

Step 4 

old-register-checksum

Example:

RP/0/RP0/CPU0:router(config-pim-ipv4)# old-register-checksum

(Optional) Allows backward compatibility on the RP that uses old register checksum methodology.

Step 5 

exit

Example:

RP/0/RP0/CPU0:router(config-pim-ipv4)# exit

Exits PIM configuration mode, and returns the router to the source configuration mode.

Step 6 

{ipv4 | ipv6} access-list name

Example:

RP/0/RP0/CPU0:router(config)# ipv4 access-list rp-access

(Optional) Enters access list configuration mode and configures the RP access list.

The access list called "rp-access" permits multicast group 239.1.1.0 0.0.255.255.

Step 7 

[sequence-number] permit source [source-wildcard]

Example:

RP/0/RP0/CPU0:router(config-ipv4-acl)# permit 239.1.1.0 0.0.255.255

(Optional) Permits multicast group 239.1.1.0 0.0.255.255 for the "rp-access" list.

Tip The commands in Step 6 and Step 7 can be combined in one command string and entered from global configuration mode like this: ipv4 access-list rp-access permit 239.1.1.0 0.0.255.255.

Step 8 

end

or

commit

Example:

RP/0/RP0/CPU0:router(config-ipv4-acl)# end

or

RP/0/RP0/CPU0:router(config-ipv4-acl)#
 commit

Saves configuration changes.

When you issue the end command, the system prompts you to commit changes:

Uncommitted changes found, commit them before 
exiting(yes/no/cancel)? 
[cancel]:
 
        

Entering yes saves configuration changes to the running configuration file, exits the configuration session, and returns the router to EXEC mode.

Entering no exits the configuration session and returns the router to EXEC mode without committing the configuration changes.

Entering cancel leaves the router in the current configuration session without exiting or committing the configuration changes.

Use the commit command to save the configuration changes to the running configuration file and remain within the configuration session.

Configuring Auto-RP to Automate Group-to-RP Mappings

This task configures the Auto-RP mechanism to automate the distribution of group-to-RP mappings in your network. In a network running Auto-RP, at least one router must operate as an RP candidate and another router must operate as an RP mapping agent.

For more information about Auto-RP, see the "Auto-RP" section.

SUMMARY STEPS

1. configure

2. router pim [address-family ipv4]

3. auto-rp candidate-rp type instance scope ttl-value [group-list access-list-name] [interval seconds]

4. auto-rp mapping-agent type number scope ttl-value [interval seconds]

5. exit

6. ipv4 access-list name

7. [sequence-number] permit source [source-wildcard]

8. end
or
commit

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

configure

Example:

RP/0/RP0/CPU0::router# configure

Enters global configuration mode.

Step 2 

router pim [address-family ipv4]

Example:

RP/0/RP0/CPU0:router(config)# router pim

Enters PIM configuration mode, or PIM address-family configuration submode.

Step 3 

auto-rp candidate-rp type instance scope ttl-value [group-list access-list-name] [interval seconds]

Example:

RP/0/RP0/CPU0:router(config-pim-ipv4)# auto-rp candidate-rp GigabitEthernet0/1/0/1 scope 31 group-list 2

Configures an RP candidate that sends messages to the CISCO-RP-ANNOUNCE multicast group (224.0.1.39).

This example sends RP announcements out all PIM-enabled interfaces for a maximum of 31 hops. The IP address by which the router wants to be identified as an RP is the IP address associated with GigabitEthernet interface 0/1/0/1.

Access list 2 designates the groups this router serves as RP.

If you specify group-list, you must configure the optional access-list command.

Step 4 

auto-rp mapping-agent type number scope ttl-value [interval seconds]

Example:

RP/0/RP0/CPU0::router(config-pim-ipv4)# auto-rp mapping-agent GigabitEthernet0/1/0/1 scope 20

Configures the router to be an RP mapping agent on a specified interface.

After the router is configured as an RP mapping agent and determines the RP-to-group mappings through the CISCO-RP-ANNOUNCE (224.0.1.39) group, the router sends the mappings in an Auto-RP discovery message to the well-known group CISCO-RP-DISCOVERY (224.0.1.40).

A PIM DR listens to this well-known group to determine which RP to use.

This example limits Auto-RP discovery messages to 20 hops.

Step 5 

exit

Example:

RP/0/RP0/CPU0::router(config-pim-ipv4)# exit

Exits PIM configuration mode and returns the router to the source configuration mode.

Step 6 

ipv4 access-list name

Example:

RP/0/RP0/CPU0:router(config)# ipv4 access-list 2

(Optional) Defines the RP access list.

Step 7 

[sequence-number] permit source [source-wildcard]

Example:

RP/0/RP0/CPU0:router(config-ipv4-acl)# permit 239.1.1.1 0.0.0.0

(Optional) Permits multicast group 239.1.1.1 for the RP access list.

Tip The commands in Step 6 and Step 7 can be combined in one command string and entered from global configuration mode like this: ipv4 access-list rp-access permit 239.1.1.1 0.0.0.0

Step 8 

end

or

commit

Example:

RP/0/RP0/CPU0:router(config-ipv4-acl)# end

or

RP/0/RP0/CPU0:router(config-ipv4-acl)# commit

Saves configuration changes.

When you issue the end command, the system prompts you to commit changes:

Uncommitted changes found, commit them before 
exiting (yes/no/cancel)? 
[cancel]:
 
        

Entering yes saves configuration changes to the running configuration file, exits the configuration session, and returns the router to EXEC mode.

Entering no exits the configuration session and returns the router to EXEC mode without committing the configuration changes.

Entering cancel leaves the router in the current configuration session without exiting or committing the configuration changes.

Use the commit command to save the configuration changes to the running configuration file and remain within the configuration session.

Configuring the Bootstrap Router

This task configures one or more candidate bootstrap routers (BSRs) and a BSR mapping agent. This task also connects and locates the candidate BSRs in the backbone portion of the network.

For more information about BSR see the "PIM Bootstrap Router" section.

SUMMARY STEPS

1. configure

2. router pim [address-family {ipv4 | ipv6}]

3. bsr candidate-bsr ip-address [hash-mask-len length] [priority value]

4. bsr candidate-rp ip-address [group-list access-list] [interval seconds] [priority value]

5. interface type interface-path-id

6. bsr border

7. exit

8. exit

9. {ipv4 | ipv6} access-list name

10. [sequence-number] permit source [source-wildcard]

or

[sequence-number] permit source-prefix dest-prefix

11. end
or
commit

12. clear pim [vrf vrf-name] [ipv4 | ipv6] bsr

13. show pim [vrf vrf-name] [ipv4 | ipv6] bsr candidate-rp

14. show pim [vrf vrf-name] [ipv4 | ipv6] bsr election

15. show pim [vrf vrf-name] [ipv4 | ipv6] bsr rp-cache

16. show pim [vrf vrf-name] [ipv4 | ipv6] group-map [ip-address-name] [info-source]

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

configure

Example:

RP/0/RP0/CPU0:router# configure

Enters global configuration mode.

Step 2 

router pim [address-family {ipv4 | ipv6}]

Example:

RP/0/RP0/CPU0:router(config)# router pim

Enters PIM configuration mode, or address-family configuration submode.

Step 3 

bsr candidate-bsr ip-address [hash-mask-len length] [priority value]

Example:

RP/0/RP0/CPU0:router(config-pim-default-ipv4)# bsr candidate-bsr 10.0.0.1 hash-mask-len 30

Configures the router to announce its candidacy as a BSR.

Step 4 

bsr candidate-rp ip-address [group-list access-list] [interval seconds] [priority value]

Example:

RP/0/RP0/CPU0:router(config-pim-default-ipv4)# bsr candidate-rp 172.16.0.0 group-list 4

Configures the router to advertise itself as a PIM Version 2 candidate RP to the BSR.

See Step 9 for group list 4 configuration.

Step 5 

interface type interface-path-id

Example:

RP/0/RP0/CPU0:router(config-pim-default-ipv4)# interface GigE 0/1/0/0

(Optional) Enters interface configuration mode for the PIM protocol.

Step 6 

bsr-border

Example:

RP/0/RP0/CPU0:router(config-pim-ipv4-if)# bsr-border

(Optional) Stops the forwarding of bootstrap router (BSR) messages on a Protocol Independent Multicast (PIM) router interface.

Step 7 

exit

Example:

RP/0/RP0/CPU0:router(config-pim-ipv4-if)# exit

(Optional) Exits PIM interface configuration mode, and returns the router to PIM configuration mode.

Step 8 

exit

Example:

RP/0/RP0/CPU0:router(config-pim-default-ipv4)# exit

Exits PIM configuration mode, and returns the router to global configuration mode.

Step 9 

{ipv4 | ipv6} access-list name

Example:

RP/0/RP0/CPU0:router(config)# ipv4
access-list 4

(Optional) Defines the candidate group list to the BSR.

Access list number 4 specifies the group prefix associated with the candidate RP address 172.16.0.0. (See Step 4).

This RP is responsible for the groups with the prefix 239.

Step 10 

[sequence-number] permit source [source-wildcard]

or

[sequence-number] permit source-prefix dest-prefix

Example:

RP/0/RP0/CPU0:router(config-ipv4-acl)# permit 239.1.1.1 0.255.255.255

(Optional) Permits multicast group 239.1.1.1 for the candidate group list.

Tip The commands in Step 6 and Step 7 can be combined in one command string and entered from global configuration mode like this: ipv4 access-list rp-access permit 239.1.1.1 0.255.255.255

Step 11 

end

or

commit

Example:

RP/0/RP0/CPU0:router(config-ipv4-acl)# end

or

RP/0/RP0/CPU0:router(config-ipv4-acl)# commit

Saves configuration changes.

When you issue the end command, the system prompts you to commit changes:

Uncommitted changes found, commit them before 
exiting(yes/no/cancel)? 
[cancel]:
 
        

Entering yes saves configuration changes to the running configuration file, exits the configuration session, and returns the router to EXEC mode.

Entering no exits the configuration session and returns the router to EXEC mode without committing the configuration changes.

Entering cancel leaves the router in the current configuration session without exiting or committing the configuration changes.

Use the commit command to save the configuration changes to the running configuration file and remain within the configuration session.

Step 12 

clear pim [vrf vrf-name] [ipv4 | ipv6] bsr

Example:

RP/0/RP0/CPU0:router# clear pim bsr

(Optional) Clears BSR entries from the PIM RP group mapping cache.

Step 13 

show pim [vrf vrf-name] [ipv4 | ipv6] bsr candidate-rp

Example:

RP/0/RP0/CPU0:router# show pim bsr candidate-rp

(Optional) Displays PIM candidate RP information for the BSR.

Step 14 

show pim [vrf vrf-name] [ipv4 | ipv6] bsr election

Example:

RP/0/RP0/CPU0:router# show pim bsr election

(Optional) Displays PIM candidate election information for the BSR.

Step 15 

show pim [vrf vrf-name][ipv4 | ipv6] bsr rp-cache

Example:

RP/0/RP0/CPU0:router# show pim bsr rp-cache

(Optional) Displays PIM RP cache information for the BSR.

Step 16 

show pim [vrf vrf-name][ipv4 | ipv6] group-map [ip-address-name] [info-source]

Example:

RP/0/RP0/CPU0:router# show pim ipv4 group-map

(Optional) Displays group-to-PIM mode mapping.

Calculating Rates per Route

This procedure enables multicast hardware forward-rate counters on a per-VRF-family basis.

SUMMARY STEPS

1. configure

2. multicast-routing [vrf vrf-name] [address-family {ipv4 | ipv6}]

3. rate-per-route

4. interface {type interface-path-id | all} enable

5. accounting per-prefix
or
accounting per-prefix forward-only

6. end
or
commit

7. show mfib [vrf vrf-name] [ipv4 | ipv6] route [rate | statistics] [* | source-address] [group-address [/prefix-length] [detail | old-output] | summary] [location node-id]

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

configure

Example:

RP/0/RP0/CPU0:router# configure

Enters global configuration mode.

Step 2 

multicast-routing [vrf vrf-name] [address-family {ipv4 | ipv6}]

Example:

RP/0/RP0/CPU0:router(config)# multicast-routing address-family ipv4

Enters multicast routing configuration mode.

The following multicast processes are started: MRIB, MFWD, PIM, IGMP, and MLD.

For IPv4, IGMP version 3 is enabled by default; for IPv6, MLD version 1 is enabled by default.

Step 3 

rate-per-route

Example:

RP/0/RP0/CPU0:router(config-mcast-default-ipv4) # rate-per-route

Enables a per (S,G) rate calculation for a particular route.

Step 4 

interface {type interface-path-id | all} enable

Example:

RP/0/RP0/CPU0:router(config-mcast-default-ipv4) # interface all enable

or

RP/0/RP0/CPU0:router(config-mcast-default-ipv4) # interface FastEthernet0/3/3/1 enable

Enables multicast routing on all interfaces.

Step 5 

accounting per-prefix

or

accounting per-prefix forward-only

Example:

RP/0/RP0/CPU0:router(config-mcast-default-ipv)# accounting per-prefix

Enables per-prefix counters present in hardware:accounting per-prefix—Enables three counters on ingress (forward, punt and drop, and two on egress (forward and punt) on every existing and new (S, G) route. The (*, G) routes are assigned a single counter.

accounting per-prefix forward-only—Enables one counter on ingress and one on egress in hardware to conserve hardware statistics resources. (Recommended for configuration of multicast VPN routing or for any line card that has a route-intensive configuration.)

Step 6 

end

or

commit

Example:

RP/0/RP0/CPU0:router(config-mcast-default-
ipv4)# end

or

RP/0/RP0/CPU0:router(config-mcast-default-
ipv4)# commit

Saves configuration changes.

When you issue the end command, the system prompts you to commit changes:

Uncommitted changes found, commit them before 
exiting(yes/no/cancel)? 
[cancel]:
 
        

Entering yes saves configuration changes to the running configuration file, exits the configuration session, and returns the router to EXEC mode.

Entering no exits the configuration session and returns the router to EXEC mode without committing the configuration changes.

Entering cancel leaves the router in the current configuration session without exiting or committing the configuration changes.

Use the commit command to save the configuration changes to the running configuration file and remain within the configuration session.

Step 7 

show mfib [vrf vrf-name] [ipv4 | ipv6] route [rate | statistics] [* | source-address] [group-address [/prefix-length] [detail | old-output] | summary] [location node-id]

Example:

RP/0/RP0/CPU0:router# show mfib vrf 12 route statistics location 0/1/cpU0

Displays route entries in the Multicast Forwarding Information Base (MFIB) table.

When the rate keyword is used with the source- and group-address, the command displays the cumulative rates per route for all line cards in the Multicast Forwarding Information Base (MFIB) table.

When the statistics keyword is used, the command displays the rate per route for one line card in the Multicast Forwarding Information Base (MFIB) table.

Configuring Multicast Nonstop Forwarding

This task configures the nonstop forwarding (NSF) feature for multicast packet forwarding for the purpose of alleviating network failures, or software upgrades and downgrades.

Although we strongly recommend that you use the NSF lifetime default values, the optional Step 4 through Step 9 allow you to modify the NSF timeout values for Protocol Independent Multicast (PIM) and Internet Group Management Protocol (IGMP) or Multicast Listener Discovery (MLD). Use these commands when PIM and IGMP or MLD are configured with nondefault interval or query intervals for join and prune operations.

Generally, configure the IGMP NSF and PIM NSF lifetime values to equal or exceed the query or join query interval. For example, if you set the IGMP query interval to 120 seconds, set the IGMP NSF lifetime to 120 seconds (or greater).

If the Cisco IOS XR software control plane does not converge and reconnect after NSF is enabled on your router, multicast packet forwarding continues for up to 15 minutes, then packet forwarding stops.

Prerequisites for Multicast Nonstop Forwarding

For NSF to operate in your multicast network, you must also enable NSF for the unicast protocols (such as IS-IS, OSPF, and BGP) that PIM relies on for Reverse Path Forwarding (RPF) information. See the appropriate configuration modules to learn how to configure NSF for unicast protocols.

SUMMARY STEPS

1. configure

2. multicast-routing [address-family {ipv4 | ipv6}]

3. nsf [lifetime seconds]

4. exit

5. router pim [address-family {ipv4| ipv6}]

6. nsf lifetime seconds

7. exit

8. router {igmp | mld}

9. nsf lifetime seconds

10. end
or
commit

11. show {igmp | mld} [old-output] nsf

12. show mfib [ipv4| ipv6] nsf [location node-id]

13. show mrib [ipv4| ipv6] [old-output] nsf

14. show pim [ipv4| ipv6] nsf

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

configure

Example:

RP/0/RP0/CPU0:router# configure

Enters global configuration mode.

Step 2 

multicast-routing [address-family {ipv4 | ipv6}]

Example:

RP/0/RP0/CPU0:router(config)# multicast-routing

Enters multicast routing configuration mode.

The following multicast processes are started: MRIB, MFWD, PIM, IGMP, and MLD.

For IPv4, IGMP version 3 is enabled by default; for IPv6, MLD version 1 is enabled by default.

Step 3 

nsf [lifetime seconds]

Example:

RP/0/RP0/CPU0:router(config-mcast)# nsf

Turns on NSF capability for the multicast routing system.

Step 4 

exit

Example:

RP/0/RP0/CPU0:router(config-mcast)# exit

(Optional) Exits multicast routing configuration mode, and returns the router to the source configuration mode.

Step 5 

router pim [address-family {ipv4 | ipv6}]

Example:

RP/0/RP0/CPU0:router(config)# router pim address-family ipv4

(Optional) Enters PIM address-family configuration submode.

Step 6 

nsf lifetime seconds

Example:

RP/0/RP0/CPU0:router(config-pim-default-ipv4)# nsf lifetime 30

(Optional) Configures the NSF timeout value for multicast forwarding route entries under the PIM process.

Note If you configure the PIM hello interval to a nondefault value, configure the PIM NSF lifetime to a value less than the hello hold time. Typically the value of the hold-time field is 3.5 times the interval time value, or 120 seconds if the PIM hello interval time is 30 seconds.

Step 7 

exit

Example:

RP/0/RP0/CPU0:router(config-pim-default-ipv4)# exit

(Optional) Exits PIM configuration mode and returns the router to the source configuration mode.

Step 8 

router {igmp | mld}

Example:
RP/0/RP0/CPU0:router(config)# router igmp

(Optional) Enters router IGMP or MLD configuration mode.

Step 9 

nsf lifetime seconds

Example:

RP/0/RP0/CPU0:router(config-igmp)# nsf lifetime 30

(Optional) Configures the NSF timeout value for multicast forwarding route entries under the IGMP or MLD process.

Step 10 

end

or

commit

Example:

RP/0/RP0/CPU0:router(config-igmp)# end

or

RP/0/RP0/CPU0:router(config-igmp)# commit

Saves configuration changes.

When you issue the end command, the system prompts you to commit changes:

Uncommitted changes found, commit them before 
exiting(yes/no/cancel)? 
[cancel]:
 
        

Entering yes saves configuration changes to the running configuration file, exits the configuration session, and returns the router to EXEC mode.

Entering no exits the configuration session and returns the router to EXEC mode without committing the configuration changes.

Entering cancel leaves the router in the current configuration session without exiting or committing the configuration changes.

Use the commit command to save the configuration changes to the running configuration file and remain within the configuration session.

Step 11 

show {igmp | mld} [old-output] nsf

Example:

RP/0/RP0/CPU0:router# show igmp nsf

(Optional) Displays the state of NSF operation in IGMP or MLD.

Step 12 

show mfib [ipv4 | ipv6] nsf [location node-id]

Example:

RP/0/RP0/CPU0:router# show mfib nsf

(Optional) Displays the state of NSF operation for the MFIB line cards.

Step 13 

show mrib [ipv4 | ipv6] [old-output] nsf

Example:

RP/0/RP0/CPU0:router# show mrib nsf

(Optional) Displays the state of NSF operation in the MRIB.

Step 14 

show pim [ipv4 | ipv6] nsf

Example:

RP/0/RP0/CPU0:router# show pim nsf

(Optional) Displays the state of NSF operation for PIM.

Configuring Multicast VPN

The following tasks configure multicast VPN (MVPN):

Enabling a VPN for Multicast Routing (required)

"Configuring BGP to Advertise VRF Routes for Multicast VPN from PE to PE" (required)
See the module "Implementing BGP on Cisco IOS XR Software" in Cisco IOS XR Routing Configuration Guide.

Configuring an MDT Address Family Session in BGP as a PE-to- PE Protocol (optional for PIM-SM MDT groups; required for PIM-SSM MDT groups)

See the "Configuring an MDT Address Family Session in BGP" section inCisco IOS XR Routing Configuration Guide.

Configuring a provider-edge-to-customer-edge protocol (optional)

See the "Configuring BGP as a PE-CE Protocol," "Configuring OSPF as a PE-to-CE Protocol," and "Configuring EIGRP as a PE-to CE Protocol" sections in Cisco IOS XR Routing Configuration Guide.

Specifying the PIM VRF Instance (optional)

Specifying the IGMP VRF Instance (optional)

Configuring the MDT Source per VRF (optional)

For an examples of end-to-end MVPN configuration, see Configuring IPv4 Multicast VPN: Example.

Prerequisites for Multicast VPN

When configuring MVPN, you must meet the following prerequisites:

PIM and multicast forwarding must be configured on all interfaces used by multicast traffic. In an MVPN, you must enable PIM and multicast forwarding for the following interfaces:

Physical interface on a provider edge (PE) router that is connected to the backbone.

Interface used for BGP peering source address.

Any interfaces configured as PIM rendezvous points.


Note PIM and multicast forwarding are enabled in multicast routing configuration mode. No additional configuration is required in router pim mode to enable the PIM protocol.


Interfaces in the VPN intended for use in forwarding multicast traffic must be enabled for PIM and multicast forwarding.

BGP should already be configured and operational on all routers that are sending or receiving multicast traffic.

To enable MVPN, you must include a VPN IPv4 address-family (AFI) in your BGP configuration. See Restrictions for Multicast VPN for Multicast Routing. (See also the "Enabling BGP Routing" section in Cisco IOS XR Routing Configuration Guide.)

All PE routers in the multicast domain must be running a Cisco IOS XR software image that supports MVPN.

Multicast forwarding must be configured for the global IPv4 address family.

Each multicast SM VRF domain must have an associated PIM rendezvous point (RP) definition. Using Auto-RP and the bootstrap router (BSR), you may configure RP services in the MVPN on the customer-edge (CE) device because the MVPN learns about the RP dynamically. The VRF interface can be used as a listener on the PE device.

To enable static RP services, you must configure each and every device in the domain for this purpose.

Restrictions for Multicast VPN for Multicast Routing

Configuration of the MDT source on a per-VRF basis is only supported on IPv4.

Enabling a VPN for Multicast Routing

This task enables multicast VPN routing for IPv4.

The MDT group address is used by provider edge (PE) routers to form a virtual PIM "neighborship" for the MDT. This enables the PEs to communicate with other PEs in the VRF as if they shared a LAN.

When sending customer VRF traffic, PEs encapsulate the traffic in their own (S,G) state, where the G is the MDT group address, and the S is the MDT source for the PE. By joining the (S,G) MDT of its PE neighbors, a PE router is able to receive the encapsulated multicast traffic for that VRF.

Although the VRF itself may have many multicast sources sending to many groups, the provider network needs only to install state for one group per VRF, in other words, the MDT group.

SUMMARY STEPS

1. configure

2. multicast-routing

3. address-family ipv4

4. nsf

5. mdt source type interface-path-id

6. interface all enable

7. vrf vrf-name [address-family {ipv4]

8. mdt default mdt-group-address

9. mdt data mdt-group-address/prefix-length threshold threshold acl-name

10. interface all enable

11. end
or
commit

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

configure

Example:

RP/0/CP0/CPU0:router# configure

Enters global configuration mode.

Step 2 

multicast-routing

Example:
RP/0/CP0/CPU0:router(config)# multicast-routing 

Enters multicast routing configuration mode.

Step 3 

address-family ipv4

Example:

RP/0/CP0/CPU0:router(config-mcast)# address-family ipv4

Note Enters ipv4 address-family submode.

Step 4 

nsf

Example:

RP/0/CP0/CPU0:router(config-mcast-default-ipv4) # nsf

Specifies that nonstop forwarding (NSF) maintains the forwarding state in case of a disruption to a multicast process.

Step 5 

mdt source type interface-path-id

Example:
RP/0/CP0/CPU0:router(config-mcast-default-ipv4)
# mdt source GigE 0/1/0/0

Specifies the MDT source address.

Note The MDT source interface is recommended to use BGP peering update-source interface, however, can also use another interface in default VRF.

Step 6 

interface all enable

Example:
RP/0/CP0/CPU0:router(config-mcast-default-ipv4)
# interface all enable

Enables multicast routing and forwarding on all new and existing interfaces. You can also enable individual interfaces.


Caution To avoid any possibility of a reverse-path forwarding (RPF) failure, you should proactively enable any interfaces that might possibly carry multicast traffic.

Step 7 

vrf vrf_A [address-family {ipv4}]

Specifies the virtual routing and forwarding instance for the ipv4 address family.

Step 8 

mdt default mdt-group-address

Example:
RP/0/CP0/CPU0:router(config-mcast-vrf_A-ipv4)# 
mdt default 239.23.2.1

Note Specifies the multicast distribution tree (MDT) default group address.

Step 9 

mdt data mdt-group-address/prefix-length threshold threshold acl-name

Example:
RP/0/CP0/CPU0:router(config-mcast-vrf_A-ipv4)# 
mdt data 239.23.3.0/24 threshold 1200 acl-A

(IPv4 MVPN configuration only) Specifies the multicast group address range to be used for data MDT traffic.

Note This group range should not overlap the MDT default group.

This is an optional command. The default threshold beyond which traffic is sent using a data MDT group is 1 kbps. However, you may configure a higher threshold, if desired.

You may also, optionally, configure an access list to limit the number of groups to be tunneled through a data MDT group. Traffic from groups not on the access-list continues to be tunneled using the default MDT group.

Step 10 

interface all enable

Example:
RP/0/CP0/CPU0:router(config-mcast-default-ipv4)
# interface all enable

Enables multicast routing and forwarding on all new and existing interfaces.

Step 11 

end

or

commit

Example:

RP/0/CP0/CPU0:router(config-mcast-default-ipv4) # end

or

RP/0/CP0/CPU0:router(config-mcast-default-ipv4) # commit

Saves configuration changes.

When you issue the end command, the system prompts you to commit changes:

Uncommitted changes found, commit them before 
exiting (yes/no/cancel)? 
[cancel]:
 
        

Entering yes saves configuration changes to the running configuration file, exits the configuration session, and returns the router to EXEC mode.

Entering no exits the configuration session and returns the router to EXEC mode without committing the configuration changes.

Entering cancel leaves the router in the current configuration session without exiting or committing the configuration changes.

Use the commit command to save the configuration changes to the running configuration file and remain within the configuration session.

Specifying the PIM VRF Instance

If you are configuring Protocol Independent Multicast in sparse mode (PIM-SM) in the MVPN, you may also need to configure a rendezvous point (RP). This task specifies the optional PIM VPN instance.

SUMMARY STEPS

1. configure

2. router pim vrf vrf-name address-family{ipv4 | ipv6}

3. rp-address ip-address [group-access-list-number] [override]

4. end
or
commit

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

configure

Example:

RP/0/RP0/CPU0:router# configure

Enters global configuration mode.

Step 2 

router pim vrf vrf-name address-family {ipv4 | ipv6}

Example:
RP/0/RP0/CPU0:router(config)# router pim vrf 
vrf_A address-family ipv4

Enters PIM address-family configuration submode and configures the PIM VRF for either an IPv4 or IPv6 address family.

Step 3 

rp-address ip-address [group-access-list-name] [bidir] [override]

Example:
RP/0/RP0/CPU0:router(config-pim-vrf_A-ipv4)# 
rp-address 10.0.0.0 

Configures the PIM rendezvous point (RP) address:

group-access-list-name = Specifies an access list of groups to be mapped to a given RP.

bidir = Specifies a bidirectional RP.

override = Specifies that a static RP configuration should override auto-RP and the bootstrap router (BSR).

Step 4 

end

or

commit

Example:

RP/0/RP0/CPU0:router(config-pim-vrf_A-ipv4)#  end

or

RP/0/RP0/CPU0:router(config-pim-vrf_A-ipv4)# commit

Saves configuration changes.

When you issue the end command, the system prompts you to commit changes:

Uncommitted changes found, commit them before 
exiting (yes/no/cancel)? 
[cancel]:
 
        

Entering yes saves configuration changes to the running configuration file, exits the configuration session, and returns the router to EXEC mode.

Entering no exits the configuration session and returns the router to EXEC mode without committing the configuration changes.

Entering cancel leaves the router in the current configuration session without exiting or committing the configuration changes.

Use the commit command to save the configuration changes to the running configuration file and remain within the configuration session.

Specifying the IGMP VRF Instance

This task specifies the IGMP VPN routing and forwarding (VRF) instance.

SUMMARY STEPS

1. configure

2. router igmp

3. vrf vrf-name

4. end
or
commit

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

configure

Example:

RP/0/RP0/CPU0:router# configure

Enters global configuration mode.

Step 2 

router igmp

Example:
RP/0/RP0/CPU0:router(config)# router igmp

Enters IGMP configuration mode.

Step 3 

vrf vrf-name

Example:
RP/0/RP0/CPU0:router(config-igmp)# vrf vrf_B

Configures a VRF instance.

Step 4 

end

or

commit

Example:

RP/0/RP0/CPU0:router(config-igmp-vrf_B)# end

or

RP/0/RP0/CPU0:router(config-igmp-vrf_B)# commit

Saves configuration changes.

When you issue the end command, the system prompts you to commit changes:

Uncommitted changes found, commit them before 
exiting (yes/no/cancel)? 
[cancel]:
 
        

Entering yes saves configuration changes to the running configuration file, exits the configuration session, and returns the router to EXEC mode.

Entering no exits the configuration session and returns the router to EXEC mode without committing the configuration changes.

Entering cancel leaves the router in the current configuration session without exiting or committing the configuration changes.

Use the commit command to save the configuration changes to the running configuration file and remain within the configuration session.

Configuring the MDT Source per VRF

This optional feature lets you change the default routing mechanism in a multicast VPN network topology, which routes all unicast traffic through a BGP peering loopback configured on a default VRF. Instead, you may configure a loopback that allows you to specify the MDT source using a specific VRF, as opposed to the default VRF. This overrides the current behavior and updates BGP as part of a MDT group. BGP then modifies the source and connector attributes in the MDT SAFI and VPN IPv4 updates.

For VRFs on which the MDT source is not configured, the MDT source for the default VRF is applied. Also, when the MDT source on a VRF is unconfigured, the configuration of the MDT source default VRF takes effect.


Note In the configuration below, the default VRF does not require explicit reference in Step 3.


SUMMARY STEPS

1. configure

2. multicast-routing

3. mdt source interface type interface-path-id


Note This is the default VRF.


4. vrf vrf-name mdt source loopback interface-path-id


Note This is the first specified VRF.


5. Repeat the foregoing step as many times as needed to create other VRFs.

6. end
or
commit

7. show pim vrf all mdt interface

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

configure

Example:

RP/0/RP0/CPU0:router# configure

Enters global configuration mode.

Step 2 

multicast-routing

Example:

RP/0/RP0/CPU0:router(config)# multicast-routing

RP/0/RP0/CPU0:router(config-mcast)#

Enables IP multicast routing and forwarding.

Step 3 

mdt source loopback interface-path-id

Example:

RP/0/RP0/CPU0:router(config-mcast)# mdt source loopback 0

Configures the interface used to set the MDT source address for MVPN, using the default VRF.

Note The MDT source command under default VRF is required to enable MVPN.

Step 4 

vrf vrf-name mdt source loopback interface-path-id

Example:

RP/0/RP0/CPU0:router(config-mcast)# vrf 101 mdt source loopback 1

Configures a second interface by specifying a particular VRF on a loopback to override the default VRF.

Step 5 

Repeat the foregoing step as many times as needed to create other VRFs.

Example:

RP/0/RP0/CPU0:router(config-mcast)# vrf 102 mdt source loopback 2

Step 6 

end
or
commit

Example:

RP/0/RP0/CPU0:router(config-mcast)# commit

Saves configuration changes.

When you issue the end command, the system prompts you to commit changes:

Uncommitted changes found, commit them 
before exiting (yes/no/cancel)? 
[cancel]:
 
        

Entering yes saves configuration changes to the running configuration file, exits the configuration session, and returns the router to EXEC mode.

Entering no exits the configuration session and returns the router to EXEC mode without committing the configuration changes.

Entering cancel leaves the router in the current configuration session without exiting or committing the configuration changes.

Use the commit command to save the configuration changes to the running configuration file and remain within the configuration session.

Step 7 

show pim vrf all mdt interface

Example:

RP/0/RP0/CPU0:router# show pim vrf

all mdt interface

multicast-routing

vrf default address-family ipv4

mdt source Loopback0

!

vrf 101 address-family ipv4

mdt default ipv4 239.1.1.1

mdt source Loopback1

!

vrf 102 address-family ipv4

mdt default ipv4 239.1.1.2

mdt source Loopback2

!

vrf 103 address-family ipv4

mdt default ipv4 239.1.1.3

!

Displays all MDT data streams.

In this example, loopback 1 is the per-VRF MDT source.

Configuring Multitopology Routing

This set of procedures configures multitopology routing, which is used by PIM for reverse-path forwarding (RPF) path selection.

"Configuring a Global Topology and Associating It with an Interface" (required)
For information, see Cisco IOS XR Routing Configuration Guide.

"Enabling an IS-IS Topology" (required)
For information, see Cisco IOS XR Routing Configuration Guide.

"Placing an Interface in a Topology in IS-IS" (required)
For information, see Cisco IOS XR Routing Configuration Guide.

"Configuring a Routing Policy" (required)
For information, see Cisco IOS XR Routing Configuration Guide.

"Configuring an RPF Topology in PIM" section (required)

For an example of multitopology routing, see Configuring Multitopology Routing: Example.

Restrictions for Configuring Multitopology Routing

Only the default VRF is currently supported in a multitopology solution.

Only protocol-independent multicast (PIM) and intermediate system-intermediate system (IS-IS) routing protocols are currently supported.

Topology selection is restricted solely to (S, G) route sources for both SM and SSM. Static and IS-IS are the only interior gateway protocols (IGPs) that support multitopology deployment.

For non-(S, G) route sources like a rendezvous point or bootstrap router (BSR), or when a route policy is not configured, the current policy default remains in effect. In other words, either a unicast-default or multicast-default table is selected for all sources based on any of the following configurations:

Open Shortest Path First (OSPF)

Intermediate System-to-Intermediate System (IS-IS)

Multiprotocol Border Gateway Protocol (MBGP)


Note Although both multicast and unicast keywords are available when using the address-family {ipv4 | ipv6} command in routing policy language (RPL), only topologies under multicast SAFI can be configured globally.


Information About Multitopology Routing

Configuring multitopology networks requires the following tasks:

"Configuring a Global Topology and Associating It with an Interface" (required)
For information, see Cisco IOS XR Routing Configuration Guide.

"Enabling an IS-IS Topology" (required)
For information, see Cisco IOS XR Routing Configuration Guide.

"Placing an Interface in a Topology in IS-IS" (required)
For information, see Cisco IOS XR Routing Configuration Guide.

"Configuring a Routing Policy" (required)
For information, see Cisco IOS XR Routing Configuration Guide.

"Configuring an RPF Topology in PIM" section (required)

For an example of multitopology routing, see Configuring Multitopology Routing: Example

Configuring an RPF Topology in PIM

SUMMARY STEPS

1. configure

2. router pim address-family {ipv4 | ipv6}

3. rpf topology route-policy policy-name

4. exit

5. multicast-routing address family {ipv4 | ipv6}

6. interface all enable

7. end
or
commit

8. show pim [vrf vrf-name] [ipv4 | ipv6] [{unicast | multicast | safi-all} topology {table-name | all}] rpf [ip-address | hash | summary | route-policy]

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

configure

Example:

RP/0/RP0/CPU0:router# configure

Enters global configuration mode.

Step 2 

router pim address-family {ipv4 | ipv6}

Example:

RP/0/RP0/CPU0:router(config)#

RP/0/RP0/CPU0:router(config-pim-default-ipv64)#

Enters PIM address-family configuration submode for the IP prefix you select.

Step 3 

rpf topology route-policy policy-name

Example:

RP/0/RP0/CPU0:router(config-pim-default-ipv4)# rpf topology route-policy mtpolicy

Assigns a given routing policy to an RPF topology table.

Step 4 

exit

Example:

RP/0/RP0/CPU0:router(config-pim-default-ipv64)# exit

RP/0/RP0/CPU0:router(config)#

Exits pim address-family configuration submode and returns you to global configuration mode.

Step 5 

multicast-routing address-family {ipv4 | ipv6}

Example:

RP/0/RP0/CPU0:router(config)# multicast-routing address-family ipv4

Enters multicast address-family configuration submode.

Step 6 

interface all enable

Example:

RP/0/RP0/CPU0::router(config-mcast-default-
ipv4)# interface all enable

Enables multicast routing and forwarding on all new and existing interfaces.

Step 7 

end

or

commit

Example:

RP/0/RP0/CPU0:router(config-mcast-default-ipv4) # end

or

RP/0/RP0/CPU0:router(config-mcast-default-ipv4) # commit

Saves configuration changes.

When you issue the end command, the system prompts you to commit changes:

Uncommitted changes found, commit them before 
exiting(yes/no/cancel)? 
[cancel]:
 
        

Entering yes saves configuration changes to the running configuration file, exits the configuration session, and returns the router to EXEC mode.

Entering no exits the configuration session and returns the router to EXEC mode without committing the configuration changes.

Entering cancel leaves the router in the current configuration session without exiting or committing the configuration changes.

Use the commit command to save the configuration changes to the running configuration file and remain within the configuration session.

Step 8 

show pim [vrf vrf-name] [ipv4 | ipv6] [{unicast | multicast | safi-all} topology {table-name | all}] rpf [ip-address | hash | summary | route-policy]

Example:

RP/0/RP0/CPU0:router# show pim vrf mtt rpf ipv4 multicast topology all rpf

Shows PIM RPF entries for one or more tables.

Interconnecting PIM-SM Domains with MSDP

To set up an MSDP peering relationship with MSDP-enabled routers in another domain, you configure an MSDP peer to the local router.

If you do not want to have or cannot have a BGP peer in your domain, you could define a default MSDP peer from which to accept all Source-Active (SA) messages.

Finally, you can change the Originator ID when you configure a logical RP on multiple routers in an MSDP mesh group.

Prerequisites for Interconnecting PIM-SM Domains with MSDP

You must configure MSDP default peering, if the addresses of all MSDP peers are not known in BGP or multiprotocol BGP.

SUMMARY STEPS

1. configure

2. interface type interface-path-id

3. ipv4 address address mask

4. end

5. router msdp

6. default-peer ip-address [prefix-list list]

7. originator-id type interface-path-id

8. peer peer-address

9. connect-source type interface-path-id

10. mesh-group name

11. remote-as as-number

12. end
or
commit

13. show msdp [ipv4] globals

14. show msdp [ipv4] peer [peer-address]

15. show msdp [ipv4] rpf rpf-address

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

configure

Example:

RP/0/RP0/CPU0:router# configure

Enters global configuration mode.

Step 2 

interface type interface-path-id

Example:

RP/0/RP0/CPU0:router(config)# interface loopback 0

(Optional) Enters interface configuration mode to define the IPv4 address for the interface.

Note This step is required if you specify an interface type and number whose primary address becomes the source IP address for the TCP connection.

Step 3 

ipv4 address address mask

Example:

RP/0/RP0/CPU0:router(config-if)# ipv4 address 10.0.1.3 255.255.255.0

(Optional) Defines the IPv4 address for the interface.

Note This step is required only if you specify an interface type and number whose primary address becomes the source IP address for the TCP connection. See optional for information about configuring the connect-source command.

Step 4 

exit

Example:

RP/0/RP0/CPU0:router(config-if)# end

Exits interface configuration mode, and returns the router to global configuration mode.

Step 5 

router msdp
Example:
RP/0/RP0/CPU0:router(config)# router msdp

Enters MSDP protocol configuration mode.

Step 6 

default-peer ip-address [prefix-list list]

Example:

RP/0/RP0/CPU0:router(config-msdp)# default-peer 172.23.16.0

(Optional) Defines a default peer from which to accept all MSDP SA messages.

Step 7 

originator-id type interface-path-id

Example:

RP/0/RP0/CPU0:router(config-msdp)# originator-id pos 0/1/1/0

(Optional) Allows an MSDP speaker that originates a (Source-Active) SA message to use the IP address of the interface as the RP address in the SA message.

Step 8 

peer peer-address

Example:

RP/0/RP0/CPU0:router(config-msdp)# peer 172.31.1.2

Enters MSDP peer configuration mode and configures an MSDP peer.

Configure the router as a BGP neighbor.

If you are also BGP peering with this MSDP peer, use the same IP address for MSDP and BGP. You are not required to run BGP or multiprotocol BGP with the MSDP peer, as long as there is a BGP or multiprotocol BGP path between the MSDP peers.

Step 9 

connect-source type interface-path-id

Example:

RP/0/RP0/CPU0:router(config-msdp-peer)# connect-source loopback 0

(Optional) Configures a source address used for an MSDP connection.

Step 10 

mesh-group name

Example:

RP/0/RP0/CPU0:router(config-msdp-peer)# mesh-group internal

(Optional) Configures an MSDP peer to be a member of a mesh group.

Step 11 

remote-as as-number

Example:

RP/0/RP0/CPU0:router(config-msdp-peer)# remote-as 250

(Optional) Configures the remote autonomous system number of this peer.

Step 12 

end

or

commit

Example:

RP/0/RP0/CPU0:router(config-msdp-peer)# 
end

or

RP/0/RP0/CPU0:router(config-msdp-peer)# commit

Saves configuration changes.

When you issue the end command, the system prompts you to commit changes:

Uncommitted changes found, commit them before 
exiting(yes/no/cancel)? 
[cancel]:
 
        

Entering yes saves configuration changes to the running configuration file, exits the configuration session, and returns the router to EXEC mode.

Entering no exits the configuration session and returns the router to EXEC mode without committing the configuration changes.

Entering cancel leaves the router in the current configuration session without exiting or committing the configuration changes.

Use the commit command to save the configuration changes to the running configuration file and remain within the configuration session.

Step 13 

show msdp [ipv4] globals

Example:

RP/0/RP0/CPU0:router# show msdp globals

Displays the MSDP global variables.

Step 14 

show msdp [ipv4] peer [peer-address]

Example:

RP/0/RP0/CPU0:router# show msdp peer 172.31.1.2

Displays information about the MSDP peer.

Step 15 

show msdp [ipv4] rpf rpf-address

Example:

RP/0/RP0/CPU0:router# show msdp rpf 172.16.10.13

Displays the RPF lookup.

Controlling Source Information on MSDP Peer Routers

Your MSDP peer router can be customized to control source information that is originated, forwarded, received, cached, and encapsulated.

When originating Source-Active (SA) messages, you can control to whom you will originate source information, based on the source that is requesting information.

When forwarding SA messages you can do the following:

Filter all source/group pairs

Specify an extended access list to pass only certain source/group pairs

Filter based on match criteria in a route map

When receiving SA messages you can do the following:

Filter all incoming SA messages from an MSDP peer

Specify an extended access list to pass certain source/group pairs

Filter based on match criteria in a route map

In addition, you can use time to live (TTL) to control what data is encapsulated in the first SA message for every source. For example, you could limit internal traffic to a TTL of eight hops. If you want other groups to go to external locations, you send those packets with a TTL greater than eight hops.

By default, MSDP automatically sends SA messages to peers when a new member joins a group and wants to receive multicast traffic. You are no longer required to configure an SA request to a specified MSDP peer.

SUMMARY STEPS

1. configure

2. router msdp

3. sa-filter {in | out} {ip-address | peer-name} [list access-list-name] [rp-list access-list-name]

4. cache-sa-state [list access-list-name] [rp-list access-list-name]

5. ttl-threshold ttl-value

6. exit

7. ipv4 access-list name [sequence-number] permit source [source-wildcard]

8. end
or
commit

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

configure

Example:

RP/0/RP0/CPU0:router# configure

Enters global configuration mode.

Step 2 

router msdp

Example:
RP/0/RP0/CPU0:router(config)# router msdp

Enters MSDP protocol configuration mode.

Step 3 

sa-filter {in | out} {ip-address | peer-name} [list access-list-name] [rp-list access-list-name]

Example:

RP/0/RP0/CPU0:router(config-msdp)# sa-filter out router.cisco.com list 100

Configures an incoming or outgoing filter list for messages received from the specified MSDP peer.

If you specify both the list and rp-list keywords, all conditions must be true to pass any source, group (S, G) pairs in outgoing Source-Active (SA) messages.

You must configure the ipv4 access-list command in Step 7.

If all match criteria are true, a permit from the route map passes routes through the filter. A deny filters routes.

This example allows only (S, G) pairs that pass access list 100 to be forwarded in an SA message to the peer named router.cisco.com.

Step 4 

cache-sa-state [list access-list-name] [rp-list access-list-name]

Example:

RP/0/RP0/CPU0:router(config-msdp)# cache-sa-state 100

Creates and caches source/group pairs from received Source-Active (SA) messages and controls pairs through access lists.

Step 5 

ttl-threshold ttl-value

Example:

RP/0/RP0/CPU0:router(config-msdp)# ttl-threshold 8

(Optional) Limits which multicast data is sent in SA messages to an MSDP peer.

Only multicast packets with an IP header TTL greater than or equal to the ttl-value argument are sent to the MSDP peer specified by the IP address or name.

Use this command if you want to use TTL to examine your multicast data traffic. For example, you could limit internal traffic to a TTL of 8. If you want other groups to go to external locations, send those packets with a TTL greater than 8.

This example configures a TTL threshold of eight hops.

Step 6 

exit

Example:
RP/0/RP0/CPU0:router(config-msdp)# exit

Exits the current configuration mode.

Step 7 

ipv4 access-list name [sequence-number] permit source [source-wildcard]

Example:

RP/0/RP0/CPU0:router(config)# ipv4 access-list 100 20 permit 239.1.1.1 0.0.0.0

Defines an IPv4 access list to be used by SA filtering.

In this example, the access list 100 permits multicast group 239.1.1.1.

The ipv4 access-list command is required if the keyword list is configured for SA filtering in Step 3.

Step 8 

end

or

commit

Example:

RP/0/RP0/CPU0:router(config-ipv4-acl)# end

or

RP/0/RP0/CPU0:router(config-ipv4-acl)# commit

Saves configuration changes.

When you issue the end command, the system prompts you to commit changes:

Uncommitted changes found, commit them before 
exiting(yes/no/cancel)? 
[cancel]:
 
        

Entering yes saves configuration changes to the running configuration file, exits the configuration session, and returns the router to EXEC mode.

Entering no exits the configuration session and returns the router to EXEC mode without committing the configuration changes.

Entering cancel leaves the router in the current configuration session without exiting or committing the configuration changes.

Use the commit command to save the configuration changes to the running configuration file and remain within the configuration session.

Configuring MSDP MD5 Password Authentication

This task describes how to configure Multicast Source Discovery Protocol (MSDP) MD5 password authentication.

SUMMARY STEPS

1. configure

2. router msdp

3. peer peer-address

4. password {clear | encrypted} password

5. end
or
commit

6. show mfib [vrf vrf-name] [ipv4 | ipv6] hardware route {* | source-address | group-address [/prefix-length]} location node-id

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

configure

Example:

RP/0/RP0/CPU0:router# configure

Enters global configuration mode.

Step 2 

router msdp

Example:

RP/0/RP0/CPU0:router(config)# router msdp

Enters MSDP configuration mode.

Step 3 

peer peer-address

Example:

RP/0/RP0/CPU0:router(config-msdp)# peer 10.0.5.4

Configures the MSDP peer.

Step 4 

password {clear | encrypted} password

Example:

RP/0/RP0/CPU0:router(config-msdp-peer)# password encrypted a34bi5m

Configures the password.

Step 5 

end

or

commit

Example:

RP/0/RP0/CPU0:router(config-msdp-peer)# 
end

or

RP/0/RP0/CPU0:router(config-msdp-peer)# commit

Saves configuration changes.

When you issue the end command, the system prompts you to commit changes:

Uncommitted changes found, commit them before 
exiting(yes/no/cancel)? 
[cancel]:
 
        

Entering yes saves configuration changes to the running configuration file, exits the configuration session, and returns the router to EXEC mode.

Entering no exits the configuration session and returns the router to EXEC mode without committing the configuration changes.

Entering cancel leaves the router in the current configuration session without exiting or committing the configuration changes.

Use the commit command to save the configuration changes to the running configuration file and remain within the configuration session.

Step 6 

show mfib [vrf vrf-name] [ipv4 | ipv6] hardware route {* | source-address | group-address [/prefix-length]} location node-id

Example:

RP/0/RP0/CPU0:router# show mfib hardware route * location 0/1/cpu0

Displays multicast routes configured with multicast QoS and the associated parameters.

Multicast only fast reroute (MoFRR)

Feature Overview

MoFRR allows fast reroute for multicast traffic on a multicast router. MoFRR minimizes packet loss in a network when node or link failures occur(at the topology merge point). It works by making simple enhancements to multicast routing protocols.

MoFRR involves transmitting a multicast join message from a receiver towards a source on a primary path and transmitting a secondary multicast join message from the receiver towards the source on a backup path. Data packets are received from the primary and secondary paths. The redundant packets are discarded at topology merge points with the help of Reverse Path Forwarding (RPF) checks. When a failure is detected on the primary path, the repair occurs locally by changing the interface on which packets are accepted to the secondary interface, thus improving the convergence times in the event of a node or link failure on the primary path.

Currently MoFRR is supported on Equal Cost MultiPath (ECMP) topologies only. XML support is available for MoFRR.

Operating Modes of MoFRR

RIB-based MoFRR—Supports Cisco CRS-1 and XR12000 series routers; the RIB version is configured at the software level and is based on routing convergence. RIB events are used as trigger for switchover.

Flow-based MoFRR—Supports the Cisco ASR 9000 Series Aggregation Services Router. Flow-based exposes the primary and secondary RPF interfaces to the forwarding plane, with switchover occurring entirely at the hardware level.

Faster convergence is obtainable in Flow-based MoFRR by monitoring the packet counts of the primary stream. If no activity is detected for 30 ms, the switch over is triggered to the backup stream and the traffic loss is within 50 ms.

Configuring MoFRR

RIB-based MoFRR

SUMMARY STEPS

1. configure

2. router pim

3. mofrr rib acl-name

4. end or commit

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

configure

Example:

RP/0/RP0/CPU0:router# configure

Enters global configuration mode.

Step 2 

router pim

RP/0/RP0/CPU0:router(config)# router pim

Enters the PIM configuration mode.

Step 3 

mofrr rib acl-name

Example:

RP/0/RP0/CPU0:router(pim)# mofrr rib acl1

Enter the ACL name.

Step 4 

end or commit class-map

Example:

RP/0/RP0/CPU0:router(pim)# commit

Saves the configuration changes.

Point-to-Multipoint Traffic Engineering Label-Switched Multicast

IP multicast was traditionally used for IPTV broadcasting and content delivery services. MPLS-TE (traffic engineering) is fast replacing the IP multicast technique because of the various advantages of MPLS-TE, such as:

Fast re-routing and restoration in case of link/ node failure

Bandwidth guarantee

Explicit path setting along with off-line computation

MPLS supports point-to-point path. However, in order to use MPLS for multicast service, MPLS has to be extended to handle point-to-multipoint paths. A reliable solution to signal Point-to-Multipoint (P2MP) label switched paths(LSP) is the Point-to-Multipoint TE LSP. This solution uses the Resource Reservation Protocol- Traffic Engineering (RSVP-TE) extension as the signaling protocol for establishing P2MP TE LSPs.

Point to Multipoint LSP(P2MP)

P2MP LSP is unidirectional. In case of native IP multicast, the multicast forwarding always has to perform an acceptance check. This check ensures all multicast packets undergo a RPF check to ensure that the packets have arrived on the correct interface in the direction of the source. However, the acceptance check with MPLS forwarding may be different in case of an unicast or upstream label.

Depending on the multicast signaling protocol, the labeled packet may require an additional L3 lookup at the P and PE routers in order to forward the multicast packet to the physical interfaces according to multicast routing. In this case, the incoming P2MP LSP as the incoming interface for the received multicast packet must also be available to the multicast forwarding plane during the L3 lookup.

Multicast Routing Protocol support for P2MP

All multicast routing protocols support P2MP TE LSP. At ingress node, a multicast protocol must make a mapping between the multicast traffic and the P2MP TE LSP with the configuration of static-join. At egress node, the multicast protocol must conduct a special RPF check for the multicast packet which is received from MPLS core and forward it to the customer facing interface. The RPF check is based on the configuration of static-rpf. These multicast groups which are forwarded over the P2MP TE LSPs can be specified with the static-rpf configuration in case of PIM-SSM.

Enabling Multicast Forwarding over tunnel interface (at ingress node)

This configuration is used for allowing the forwarding of the multicast packet over the specified interface.

SUMMARY STEPS

1. configure

2. multicast-routing

3. address-family {ipv4 | ipv6}

4. interface tunnel-mte range

5. enable | disable

6. end or commit

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

configure

Example:

RP/0/RP0/CPU0:router# configure

Enters global configuration mode.

Step 2 

multicast-routing

Example:
RP/0/RP0/CPU0:router(config)# multicast-routing 

Enters multicast routing configuration mode.

Step 3 

address-family {ipv4|ipv6}

Example:

RP/0/RP0/CPU0:router(config-mcast)# address-family ipv4

Enters ipv4 or ipv6 address-family submode.

Step 4 

interface tunnel-mte range

Example:

RP/0/RP0/CPU0:router(config-mcast-default-ipv4) # interface tunnel-mte 100

Specify the range. The range is 0 to 65535.

Step 5 

enable | disbale

Example:
RP/0/RP0/CPU0:router(config-mcast-default-ipv4)
# enable

If enable is set, MFIB forwards multicast packets over the interface. If disable is set, MFIB stops forwarding multicast packets over the interface.

Step 6 

end

or

commit

Example:

RP/0/RP0/CPU0:router(config-mcast-default-ipv4) # end

or

RP/0/RP0/CPU0:router(config-mcast-default-ipv4) # commit

Saves configuration changes.

When you issue the end command, the system prompts you to commit changes:

Uncommitted changes found, commit them before 
exiting (yes/no/cancel)? 
[cancel]:
 
        

Entering yes saves configuration changes to the running configuration file, exits the configuration session, and returns the router to EXEC mode.

Entering no exits the configuration session and returns the router to EXEC mode without committing the configuration changes.

Entering cancel leaves the router in the current configuration session without exiting or committing the configuration changes.

Use the commit command to save the configuration changes to the running configuration file and remain within the configuration session.

P2MP configurations at egress node and bud node

Configuring Static Reverse Path Forwarding (RPF)

SUMMARY STEPS

1. configure

2. multicast-routing

3. address-family {ipv4 | ipv6}

4. static-rpf address range prefix

5. mpls address

6. end or commit

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

configure

Example:

RP/0/RP0/CPU0:router# configure

Enters global configuration mode.

Step 2 

multicast-routing

Example:
RP/0/RP0/CPU0:router(config)# multicast-routing 

Enters multicast routing configuration mode.

Step 3 

address-family {ipv4 | ipv6}

Example:

RP/0/RP0/CPU0:router(config-mcast)# address-family ipv4

Enters ipv4 (or ipv6) address-family submode.

Step 4 

static-rpf address range prefix

Example:

RP/0/RP0/CPU0:router(config-mcast-default-ipv4) # static-rpf 10.1.1.1 32

Enter the source and prefix length.

Step 5 

mpls address

Example:
RP/0/RP0/CPU0:router(config-mcast-default-ipv4)
# mpls 10.2.2.2

Enter the source PE address of the MPLS P2MP tunnel.

Step 6 

end

or

commit

Example:

RP/0/RP0/CPU0:router(config-mcast-default-ipv4) # end

or

RP/0/RP0/CPU0:router(config-mcast-default-ipv4) # commit

Saves configuration changes.

When you issue the end command, the system prompts you to commit changes:

Uncommitted changes found, commit them before 
exiting (yes/no/cancel)? 
[cancel]:
 
        

Entering yes saves configuration changes to the running configuration file, exits the configuration session, and returns the router to EXEC mode.

Entering no exits the configuration session and returns the router to EXEC mode without committing the configuration changes.

Entering cancel leaves the router in the current configuration session without exiting or committing the configuration changes.

Use the commit command to save the configuration changes to the running configuration file and remain within the configuration session.

Configuring core tree protocol

SUMMARY STEPS

1. configure

2. multicast-routing

3. address-family {ipv4 | ipv6}

4. core-tree-protocol rsvp-te group-list name

5. end or commit

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

configure

Example:

RP/0/RP0/CPU0:router# configure

Enters global configuration mode.

Step 2 

multicast-routing

Example:
RP/0/RP0/CPU0:router(config)# multicast-routing 

Enters multicast routing configuration mode.

Step 3 

address-family {ipv4 | ipv6}

Example:

RP/0/RP0/CPU0:router(config-mcast)# address-family ipv4

Enters ipv4 (or ipv6)address-family submode.

Step 4 

core-tree-protocol rsvp-te group-list name

Example:

RP/0/RP0/CPU0:router(config-mcast-default-ipv4) # core-tree-protocol rsvp-te group-list acl1

Enters the core-tree-protocol configuration mode.

Step 5 

end

or

commit

Example:

RP/0/RP0/CPU0:router(config-mcast-default-ipv4) # end

or

RP/0/RP0/CPU0:router(config-mcast-default-ipv4) # commit

Saves configuration changes.

When you issue the end command, the system prompts you to commit changes:

Uncommitted changes found, commit them before 
exiting (yes/no/cancel)? 
[cancel]:
 
        

Entering yes saves configuration changes to the running configuration file, exits the configuration session, and returns the router to EXEC mode.

Entering no exits the configuration session and returns the router to EXEC mode without committing the configuration changes.

Entering cancel leaves the router in the current configuration session without exiting or committing the configuration changes.

Use the commit command to save the configuration changes to the running configuration file and remain within the configuration session.

Configuration Examples for Implementing Multicast Routing on Cisco IOS XR Software

This section provides the following configuration examples:

MSDP Anycast RP Configuration on Cisco IOS XR Software: Example

Bidir-PIM Configuration on Cisco IOS XR Software: Example

Calculating Rates per Route: Example

Preventing Auto-RP Messages from Being Forwarded on Cisco IOS XR Software: Example

Inheritance in MSDP on Cisco IOS XR Software: Example

Configuring IPv4 Multicast VPN: Example

Configuring Multitopology Routing: Example

MSDP Anycast RP Configuration on Cisco IOS XR Software: Example

Anycast RP allows two or more rendezvous points (RPs) to share the load for source registration and to act as hot backup routers for each other. MSDP is the key protocol that makes Anycast RP possible.

In Anycast RP, two or more RPs are configured with the same IP address on loopback interfaces. Configure the Anycast RP loopback address with a 32-bit mask, making it a host address. Configure all downstream routers to "know" that the Anycast RP loopback address is the IP address of the local RP. IP routing automatically selects the topologically closest RP for each source and receiver.

As a source may register with one RP and receivers may join to a different RP, a method is needed for the RPs to exchange information about active sources. This information exchange is done with MSDP.

In Anycast RP, all the RPs are configured to be MSDP peers of each other. When a source registers with one RP, a Source-Active (SA) message is sent to the other RPs, informing them that there is an active source for a particular multicast group. The result is that each RP knows about the active sources in the area of the other RPs. If any of the RPs fails, IP routing converges and one of the RPs becomes the active RP in more than one area. New sources register with the backup RP, and receivers join the new RP.

Note that the RP is usually needed only to start new sessions with sources and receivers. The RP facilitates the shared tree so that sources and receivers can directly establish a multicast data flow. If a multicast data flow is already directly established between a source and the receiver, an RP failure does not affect that session. Anycast RP ensures that new sessions with sources and receivers can begin at any time.

The following Anycast RP example configures Router A and Router B as Anycast RPs. The Anycast RP IP address assignment is 10.0.0.1.

Router A

interface loopback 0 
 ipv4 address 10.0.0.1/32 
 no shutdown
interface loopback 1 
 ipv4 address 10.2.0.1/32 
 no shutdown
multicast-routing 
 interfaces all enable 
router pim 
 rp-address 10.0.0.1 
router msdp 
 connect-source loopback 1 
 peer 10.2.0.2

Router B

interface loopback 0
 ipv4 address 10.0.0.1/32 
 no shutdown
interface loopback 1 
 ipv4 address 10.2.0.2/32 
 no shutdown
multicast-routing 
 interfaces all enable 
router pim 
 rp-address 10.0.0.1 
router msdp 
 connect-source loopback 1 
 peer 10.2.0.1
 
   

Apply the following configuration to all network routers:

multicast-routing 
router pim 
 rp-address 10.0.0.1 

Bidir-PIM Configuration on Cisco IOS XR Software: Example

An access list on the RP can be used to specify a list of groups to be advertised as bidirectional PIM (bidir-PIM).

The following example shows how to configure an RP for both PIM-SM and the bidir-PIM mode groups. The bidir-PIM groups are configured as 224/8 and 227/8, with the remaining multicast group range (224/4) configured as PIM-SM.

interface loopback 0 
 ipv4 address 10.0.0.1/24 
 no shutdown
interface loopback 1 
 ipv4 address 10.2.0.1/24 
 no shutdown
ipv4 access-list bidir_acl 
 10 permit 224.0.0.0 0.255.255.255 any 
 20 permit 225.0.0.0 0.255.255.255 any 
multicast-routing 
 interface all enable
router pim 
 auto-rp mapping-agent loopback 0 scope 15 interval 60 
 auto-rp candidate-rp loopback 0 scope 15 group-list bidir_acl interval 60 bidir 
 auto-rp candidate-rp loopback 1 scope 15 group-list 224/4 interval 60

Tip Issue the show pim group-map command and verify the output to ensure that the configured mappings are learned correctly.


Calculating Rates per Route: Example

The following example illustrates output from hardware counters based on rate per route for a specific source and group address location:

RP/0/RP0/CPU0:router# configure
RP/0/RP0/CPU0:router(config)# multicast-routing vrf vpn12 address-family ipv4
RP/0/RP0/CPU0:router(config-mcast-default-ipv4)# rate-per-route
RP/0/RP0/CPU0:router(config-mcast-default-ipv4)# interface all enable
RP/0/RP0/CPU0:router(config-mcast-default-ipv4)# accounting per-prefix 
RP/0/RP0/CPU0:router(config-mcast-default-ipv4)# commit
RP/0/RP0/CPU0:router(config-mcast-default-ipv4)# exit 
RP/0/RP0/CPU0:router(config-mcast)# exit
RP/0/RP0/CPU0:router(config)# exit
RP/0/RP0/CPU0:router# show mfib route rate 
 
   
IP Multicast Forwarding Rates Source Address, Group Address HW Forwarding Rates: bps 
In/pps In/bps Out/pps Out
 
   
(*,224.0.0.0/24)
bps_in /pps_in /bps_out /pps_out
N/A / N/A / N/A / N/A 
 
(*,224.0.1.39)
bps_in /pps_in /bps_out /pps_out
N/A / N/A / N/A / N/A 
 
(*,224.0.1.40)
bps_in /pps_in /bps_out /pps_out
N/A / N/A / N/A / N/A 
 
(*,232.0.0.0/8)
bps_in /pps_in /bps_out /pps_out
N/A / N/A / N/A / N/A
(30.0.70.2,225.0.0.0)
bps_in /pps_in /bps_out /pps_out
22649 / 50 / 22951 / 50
 
(30.0.70.2,225.0.0.1)
bps_in /pps_in /bps_out /pps_out
22649 / 50 / 22951 / 50
 
(30.0.70.2,225.0.0.2)
bps_in /pps_in /bps_out /pps_out
22649 / 50 / 22951 / 50
 
(30.0.70.2,225.0.0.3)
bps_in /pps_in /bps_out /pps_out
22649 / 50 / 22951 / 50
 
(30.0.70.2,225.0.0.4)
bps_in /pps_in /bps_out /pps_out
22649 / 50 / 22951 / 50
 
(30.0.70.2,225.0.0.5)
bps_in /pps_in /bps_out /pps_out
22649 / 50 / 22951 / 50
 
(30.0.70.2,225.0.0.6)
bps_in /pps_in /bps_out /pps_out
 
   

Preventing Auto-RP Messages from Being Forwarded on Cisco IOS XR Software: Example

The following example shows that Auto-RP messages are prevented from being sent out of the Packet over SONET/SDH (POS) interface 0/3/0/0. It also shows that access list 111 is used by the Auto-RP candidate and access list 222 is used by the boundary command to contain traffic on POS interface 0/3/0/0.

ipv4 access-list 111 
 10 permit 224.1.0.0 0.0.255.255 any 
 20 permit 224.2.0.0 0.0.255.255 any 
! 
!Access list 111 is used by the Auto-RP candidate.
!
ipv4 access-list 222 
 10 deny any host 224.0.1.39 
 20 deny any host 224.0.1.40 
! 
!Access list 222 is used by the boundary command to contain traffic (on POS0/3/0/0) that 
is sent to groups 224.0.1.39 and 224.0.1.40.
!
router pim
 auto-rp mapping-agent loopback 2 scope 32 interval 30 
 auto-rp candidate-rp loopback 2 scope 15 group-list 111 interval 30 
multicast-routing
 interface pos 0/3/0/0 
 boundary 222
!

Inheritance in MSDP on Cisco IOS XR Software: Example

The following MSDP commands can be inherited by all MSDP peers when configured under router MSDP configuration mode. In addition, commands can be configured under the peer configuration mode for specific peers to override the inheritance feature.

connect-source

sa-filter

ttl-threshold

If a command is configured in both the router msdp and peer configuration modes, the peer configuration takes precedence.

In the following example, MSDP on Router A filters Source-Active (SA) announcements on all peer groups in the address range 226/8 (except IP address 172.16.0.2); and filters SAs sourced by the originator RP 172.16.0.3 to 172.16.0.2.

MSDP peers (172.16.0.1, 172.16.0.2, and 172.17.0.1) use the loopback 0 address of Router A to set up peering. However, peer 192.168.12.2 uses the IPv4 address configured on the Packet-over-SONET/SDH (POS) interface to peer with Router A.

Router A

! 
ipv4 access-list 111 
 10 deny ip host 172.16.0.3 any 
 20 permit any any 
! 
 
   
ipv4 access-list 112 
 10 deny any 226.0.0.0 0.255.255.255 
 30 permit any any 
! 
router msdp 
 connect-source loopback 0 
 sa-filter in rp-list 111 
 sa-filter out rp-list 111 
 peer 172.16.0.1 
! 
peer 172.16.0.2 
 sa-filter out list 112 
! 
peer 172.17.0.1 
! 
peer 192.168.12.2 
 connect-source pos 0/2/0/0 
! 

Configuring IPv4 Multicast VPN: Example

Cisco CRS-1 Router supports only IPv4 addressing.

This end-to-end configuration example shows how to establish a multicast VPN topology (Figure 6), using two different routing protocols (OSPF or BGP) to broadcasting traffic between customer-edge(CE) routers and provider-edge (PE) routers:

Configuring MVPN to Advertise Routes Between the CE and the PE Using OSPF: Example

Configuring MVPN to Advertise Routes Between the CE and the PE Using BGP: Example

Figure 6 Topology in

MVPN Configuration on the Cisco CRS-1 Router Example

For more configuration information, see the "Configuring Multicast VPN" section of this module and also related configuration information in Cisco IOS XR Routing Configuration Guide.

Configuring MVPN to Advertise Routes Between the CE and the PE Using OSPF: Example

PE1:

!
vrf vpn1
 address-family ipv4 unicast
  import route-target
   1:1
  !
  export route-target
   1:1
  !
 !
!
interface Loopback0
 ipv4 address 1.1.1.1 255.255.255.255
!
interface Loopback1
 vrf vpn1
 ipv4 address 2.2.2.2 255.255.255.255
!
interface GigabitEthernet0/5/0/0
 vrf vpn1
 ipv4 address 101.1.1.1 255.255.255.0
!
interface TenGigE0/6/0/0
 ipv4 address 12.1.1.1 255.255.255.0
!
mpls ldp
 router-id 1.1.1.1
 interface TenGigE0/6/0/0
 !
!
multicast-routing
 vrf vpn1 address-family ipv4
  mdt data 233.1.0.0/16 threshold 3
  mdt default ipv4 232.1.1.1
  rate-per-route
  interface all enable
  accounting per-prefix
 !
 address-family ipv4
  nsf
  mdt source Loopback0
  interface all enable
  accounting per-prefix
 !
!
router bgp 100
 bgp router-id 1.1.1.1
 address-family ipv4 unicast
 !
 address-family vpnv4 unicast
 !
 address-family ipv4 mdt
 !
 neighbor 9.9.9.9
  remote-as 100
  update-source Loopback0
  address-family ipv4 unicast
  !
  address-family vpnv4 unicast
  !
  address-family ipv4 mdt
  !
 !
 vrf vpn1
  rd 1:1
  address-family ipv4 unicast
   redistribute ospf 1
  !
 !
!
router ospf 1
 vrf vpn1
  router-id 2.2.2.2
  redistribute bgp 100
  area 0
   interface Loopback1
   !
   interface GigabitEthernet0/5/0/0
   !
  !
 !
!
router ospf 100
 router-id 1.1.1.1
 area 0
  interface Loopback0
  !
  interface TenGigE0/6/0/0
  !
 !
!
router pim vrf vpn1 address-family ipv4
 rp-address 2.2.2.2
 log neighbor changes
!
router pim vrf default address-family ipv4
 rp-address 1.1.1.1
!
end

PE2:

!
vrf vpn1
 address-family ipv4 unicast
  import route-target
   1:1
  !
  export route-target
   1:1
  !
 !
!
interface Loopback0
 ipv4 address 9.9.9.9 255.255.255.255
!
interface Loopback1
 vrf vpn1
 ipv4 address 10.10.10.10 255.255.255.255
!
interface GigabitEthernet0/2/2/7
 vrf vpn1
 ipv4 address 122.1.1.1 255.255.255.0
 negotiation auto
!
interface TenGigE0/3/0/0
 ipv4 address 12.1.1.2 255.255.255.0
!
mpls ldp
 router-id 9.9.9.9
 interface TenGigE0/3/0/0
 !
!
multicast-routing
 vrf vpn1 address-family ipv4
  mdt data 233.1.0.0/16 threshold 3
  mdt default ipv4 232.1.1.1
  rate-per-route
  interface all enable
  accounting per-prefix
 !
 address-family ipv4
  nsf
  mdt source Loopback0
  interface all enable
  accounting per-prefix
 !
!
router bgp 100
 bgp router-id 9.9.9.9
 address-family ipv4 unicast
 !
 address-family vpnv4 unicast
 !
 address-family ipv4 mdt
 !
 neighbor 1.1.1.1
  remote-as 100
  update-source Loopback0
  address-family ipv4 unicast
  !
  address-family vpnv4 unicast
  !
  address-family ipv4 mdt
  !
 !
 vrf vpn1
  rd 1:1
  address-family ipv4 unicast
   redistribute ospf 1
  !
 !
!
router ospf 1
 vrf vpn1
  router-id 10.10.10.10
  redistribute bgp 100
  area 0
   interface Loopback1
   !
   interface GigabitEthernet0/2/2/7
   !
  !
 !
!
router ospf 100
 router-id 9.9.9.9
 area 0
  interface Loopback0
  !
  interface TenGigE0/3/0/0
  !
 !
!
router pim vrf vpn1 address-family ipv4
 rp-address 2.2.2.2
!
router pim vrf default address-family ipv4
 rp-address 1.1.1.1
!
end

CE4:

For information about configuring the CE router, using Cisco IOS software, see the appropriate Cisco IOS software configuration documentation.

!
interface Loopback0
 ipv4 address 101.101.101.101 255.255.255.255
!
interface GigabitEthernet0/0/0/0
 ipv4 address 101.1.1.2 255.255.255.0
!
interface GigabitEthernet0/0/0/3
 ipv4 address 11.1.1.1 255.255.255.0
!
multicast-routing
 address-family ipv4
  interface all enable
 !
!
router ospf 1
 router-id 101.101.101.101
 area 0
  interface Loopback0
  !
  interface GigabitEthernet0/0/0/0
  !
  interface GigabitEthernet0/0/0/3
  !
 !
!
router pim vrf default address-family ipv4
 rp-address 2.2.2.2
 interface Loopback0
 !
 interface GigabitEthernet0/0/0/0
 !
 interface GigabitEthernet0/0/0/3
 !
!
end

CE3:

For information about configuring the CE router, using Cisco IOS software, see the appropriate Cisco IOS software configuration documentation.

interface Loopback0
 ipv4 address 122.122.122.122 255.255.255.255
!
 
interface GigabitEthernet0/1/3/0
 ipv4 address 22.1.1.1 255.255.255.0
!
 
interface GigabitEthernet0/2/3/0
 ipv4 address 122.1.1.2 255.255.255.0
 
multicast-routing
 address-family ipv4
  interface all enable
!
router ospf 1
 router-id 122.122.122.122
 area 0 
  interface Loopback0
  !
  interface GigabitEthernet0/1/3/0
  !
  interface GigabitEthernet0/2/3/0
  !
 !
!
router pim vrf default address-family ipv4
 rp-address 2.2.2.2
 interface Loopback0
 !
 interface GigabitEthernet0/1/3/0
 !
 interface GigabitEthernet0/2/3/0
 !
!
end 

Configuring MVPN to Advertise Routes Between the CE and the PE Using BGP: Example

PE1:

vrf vpn1
 address-family ipv4 unicast
  import route-target
   1:1
  !
  export route-target
   1:1
  !
 !
!
interface Loopback0
 ipv4 address 1.1.1.1 255.255.255.255
!
interface Loopback1
 vrf vpn1
 ipv4 address 2.2.2.2 255.255.255.255
!
interface GigabitEthernet0/5/0/0
 vrf vpn1
 ipv4 address 101.1.1.1 255.255.255.0
!
interface TenGigE0/6/0/0
 ipv4 address 12.1.1.1 255.255.255.0
!
mpls ldp
 router-id 1.1.1.1
 interface TenGigE0/6/0/0
 !
!
multicast-routing
 vrf vpn1 address-family ipv4
  mdt data 233.1.0.0/16 threshold 3
  mdt default ipv4 232.1.1.1
  rate-per-route
  interface all enable
  accounting per-prefix
 !
 address-family ipv4
  nsf
  mdt source Loopback0
  interface all enable
  accounting per-prefix
 !
!
!
route-policy pass-all
  pass
end-policy
!
router bgp 100
 bgp router-id 1.1.1.1
 address-family ipv4 unicast
 !
 address-family vpnv4 unicast
 !
 address-family ipv4 mdt
 !
 neighbor 9.9.9.9
  remote-as 100
  update-source Loopback0
  address-family ipv4 unicast
  !
  address-family vpnv4 unicast
  !
  address-family ipv4 mdt
  !
 !
 vrf vpn1
  rd 1:1
  address-family ipv4 unicast
   redistribute connected
  !
  neighbor 101.1.1.2
   remote-as 400
   address-family ipv4 unicast
    route-policy pass-all in
    route-policy pass-all out
   !
  !
 !
!
router ospf 100
 router-id 1.1.1.1
 area 0
  interface Loopback0
  !
  interface TenGigE0/6/0/0
  !
 !
!
router pim vrf vpn1 address-family ipv4
 rp-address 2.2.2.2
 log neighbor changes
!
router pim vrf default address-family ipv4
 rp-address 1.1.1.1
!
end
 
   

PE2:

!
vrf vpn1
 address-family ipv4 unicast
  import route-target
   1:1
  !
  export route-target
   1:1
  !
 !
!
interface Loopback0
 ipv4 address 9.9.9.9 255.255.255.255
!
interface Loopback1
 vrf vpn1
 ipv4 address 10.10.10.10 255.255.255.255
!
interface GigabitEthernet0/2/2/7
 vrf vpn1
 ipv4 address 122.1.1.1 255.255.255.0
 negotiation auto
!
interface TenGigE0/3/0/0
 ipv4 address 12.1.1.2 255.255.255.0
!
mpls ldp
 router-id 9.9.9.9
 interface TenGigE0/3/0/0
 !
!
multicast-routing
 vrf vpn1 address-family ipv4
  mdt data 233.1.0.0/16 threshold 3
  mdt default ipv4 232.1.1.1
  rate-per-route
  interface all enable
  accounting per-prefix
 !
 address-family ipv4
  nsf
  mdt source Loopback0
  interface all enable
  accounting per-prefix
 !
!
!
route-policy pass-all
  pass
end-policy
!
router bgp 100
 bgp router-id 9.9.9.9
 address-family ipv4 unicast
 !
 address-family vpnv4 unicast
 !
 address-family ipv4 mdt
 !
 neighbor 1.1.1.1
  remote-as 100
  update-source Loopback0
  address-family ipv4 unicast
  !
  address-family vpnv4 unicast
  !
  address-family ipv4 mdt
  !
 !
 vrf vpn1
  rd 1:1
  address-family ipv4 unicast
   redistribute connected
  !
  neighbor 122.1.1.2
   remote-as 500
   address-family ipv4 unicast
    route-policy pass-all in
    route-policy pass-all out
   !
  !
 !
!
router ospf 100
 router-id 9.9.9.9
 area 0
  interface Loopback0
  !
  interface TenGigE0/3/0/0
  !
 !
!
router pim vrf vpn1 address-family ipv4
 rp-address 2.2.2.2
!
router pim vrf default address-family ipv4
 rp-address 1.1.1.1
!
end

CE4:

For information about configuring the CE router, using Cisco IOS software, see the appropriate Cisco IOS software configuration documentation.

interface Loopback0
 ipv4 address 101.101.101.101 255.255.255.255
!
interface GigabitEthernet0/0/0/0
 ipv4 address 101.1.1.2 255.255.255.0
!
interface GigabitEthernet0/0/0/3
 ipv4 address 11.1.1.1 255.255.255.0
!
multicast-routing
 address-family ipv4
  interface all enable
 !
!
!
route-policy pass-all
  pass
end-policy
!
router bgp 400
 bgp router-id 101.101.101.101
 address-family ipv4 unicast
  redistribute connected
 !
 neighbor 101.1.1.1
  remote-as 100
  address-family ipv4 unicast
   route-policy pass-all in
   route-policy pass-all out
  !
 !
!
router pim vrf default address-family ipv4
 rp-address 2.2.2.2
 interface Loopback0
 !
 interface GigabitEthernet0/0/0/0
 !
 interface GigabitEthernet0/0/0/3
 !
!
end

CE3:

For information about configuring the CE router, using Cisco IOS software, see the appropriate Cisco IOS software configuration documentation.

interface Loopback0
 ipv4 address 122.122.122.122 255.255.255.255
!
 
interface GigabitEthernet0/1/3/0
 ipv4 address 22.1.1.1 255.255.255.0
!
 
interface GigabitEthernet0/2/3/0
 ipv4 address 122.1.1.2 255.255.255.0
 
multicast-routing
 address-family ipv4
  interface all enable
!
!
!
route-policy pass-all
  pass
end-policy
!
router bgp 500
 bgp router-id 122.122.122.122
 address-family ipv4 unicast
  redistribute connected
 !
 neighbor 122.1.1.1 
  remote-as 100
  address-family ipv4 unicast
   route-policy pass-all in
   route-policy pass-all out
  !
 !
!
!
router pim vrf default address-family ipv4
 rp-address 2.2.2.2
 interface Loopback0
 !
 interface GigabitEthernet0/1/3/0
 !
 interface GigabitEthernet0/2/3/0
 !
!
end 


Configuring Multitopology Routing: Example

The following example shows the configuration required to enable a dual multicast topology. The two topologies defined are named BLUE and GREEN. Each contains one interface. IS-IS is configured so that each interface is only in the IS-IS topology, and the interfaces themselves are configured so that their connected and local routes are placed only within the appropriate routing tables.

The routing policy was configured to select which topology should be used based on the source address of the multicast flow.

!
interface GigabitEthernet0/1/0/0
 address-family ipv4 multicast topology BLUE
!
interface GigabitEthernet0/1/0/1
 address-family ipv4 multicast topology GREEN
!
router isis 1
 net 00.0000.0000.0001.00
 interface GigabitEthernet0/1/0/0
  address-family ipv4 multicast topology BLUE
 interface GigabitEthernet0/1/0/1
  address-family ipv4 multicast topology GREEN
!
 
   
route-policy mtp1
  if destination in (230.5.1.2) then
    if source in (10.10.10.10) then
      set rpf-topology ipv4 multicast topology BLUE
    else
      set rpf-topology ipv4 multicast topology GREEN
    endif
  endif
end-policy
!
 
   
router pim
 address-family ipv4
  rpf topology route-policy mtp1
 !
!
 
   
multicast-routing
 address-family ipv4 
  interface all enable
 !
!

Examples 1 and 2 illustrate routing policies that you can use in configuring PIM RPF topologies:

Example 1

route-policy mtp1
  if destination in (225.0.0.1, 225.0.0.11) then
    set rpf-topology ipv4 multicast topology t201
  elseif destination in (225.0.0.2, 225.0.0.12) then
    set rpf-topology ipv4 multicast topology t202
  elseif destination in (225.0.0.3, 225.0.0.13) then
    pass
  endif
end-policy
!

Example 2

route-policy mtp2
  if destination in (225.0.0.8) then
    set rpf-topology ipv4 multicast topology t208
  elseif destination in (225.0.0.9) then
    set rpf-topology ipv4 multicast topology t209
  elseif destination in (225.0.0.10) then
    set rpf-topology ipv4 multicast topology t210
  else
    drop
  endif
end-policy
!

Additional References

The following sections provide references related to implementing multicast routing on Cisco IOS XR software.

Related Documents

Related Topic
Document Title

Multicast command reference document

Cisco IOS XR Multicast Command Reference

Routing command reference and configuration documents

Cisco IOS XR Routing Command Reference and Cisco IOS XR Routing Configuration Guide

Information about user groups and task IDs

Configuring AAA Services on Cisco IOS XR Software module of Cisco IOS XR System Security Configuration Guide

Modular quality of service command reference document

Cisco IOS XR Modular Quality of Service Command Reference


Standards

Standards
Title

draft-ietf-pim-sm-v2-new

Protocol Independent Multicast - Sparse Mode (PIM-SM): Protocol Specification


MIBs

MIBs
MIBs Link

To locate and download MIBs using Cisco IOS XR software, use the Cisco MIB Locator found at the following URL and choose a platform under the Cisco Access Products menu: http://cisco.com/public/sw-center/netmgmt/cmtk/mibs.shtml


RFCs

RFCs
Title

RFC 2362

Protocol-Independent Multicast-Sparse Mode (PIM-SM): Protocol Specification

RFC 2385

Protection of BGP Sessions via the TCP MD5 Signature Option

RFC 2547

BGP/MPLS VPNs

RFC 2710

Multicast Listener Discovery (MLD) for IPv6

RFC 3376

Internet Group Management Protocol, Version 3

RFC 3446

Anycast Rendezvous Point (RP) mechanism using Protocol Independent Multicast (PIM) and Multicast Source Discovery Protocol (MSDP)

RFC 3618

Multicast Source Discovery Protocol (MSDP)

RFC 3810

Multicast Listener Discovery Version 2 (MLDv2) for IPv6

RFC4875

Extensions to Resource Reservation Protocol - Traffic Engineering (RSVP-TE) for Point-to-Multipoint TE Label-Switched Paths (LSPs)


Technical Assistance

Description
Link

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http://www.cisco.com/techsupport