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play_arrow Overview
- play_arrow Understanding Multicast
play_arrow Managing Group Membership
play_arrow Configuring Protocol Independent Multicast
- play_arrow Understanding PIM
  - PIM Overview
  - PIM on Aggregated Interfaces
- play_arrow Configuring PIM Basics
- play_arrow Routing Content to Densely Clustered Receivers with PIM Dense Mode
- play_arrow Routing Content to Larger, Sparser Groups with PIM Sparse Mode
- play_arrow Configuring Designated Routers
  - Understanding Designated Routers
  - Configuring a Designated Router for PIM
- play_arrow Receiving Content Directly from the Source with SSM
- play_arrow Minimizing Routing State Information with Bidirectional PIM
  - Example: Configuring Bidirectional PIM
- play_arrow Rapidly Detecting Communication Failures with PIM and the BFD Protocol
  - Configuring PIM and the Bidirectional Forwarding Detection (BFD) Protocol
- play_arrow Configuring PIM Options
  - Example: Configuring Nonstop Active Routing for PIM
  - Configuring PIM-to-IGMP and PIM-to-MLD Message Translation
- play_arrow Verifying PIM Configurations
play_arrow Configuring Multicast Routing Protocols
- play_arrow Connecting Routing Domains Using MSDP
  - Examples: Configuring MSDP
  - Configuring Multiple Instances of MSDP
- play_arrow Handling Session Announcements with SAP and SDP
  - Configuring the Session Announcement Protocol
  - Verifying SAP and SDP Addresses and Ports
- play_arrow Facilitating Multicast Delivery Across Unicast-Only Networks with AMT
  - Example: Configuring Automatic IP Multicast Without Explicit Tunnels
- play_arrow Routing Content to Densely Clustered Receivers with DVMRP
  - Examples: Configuring DVMRP
play_arrow Configuring Multicast VPNs
play_arrow General Multicast Options
- play_arrow Bit Index Explicit Replication (BIER)
- play_arrow Prevent Routing Loops with Reverse Path Forwarding
  - Examples: Configuring Reverse Path Forwarding
- play_arrow Use Multicast-Only Fast Reroute (MoFRR) to Minimize Packet Loss During Link Failures
- play_arrow Enable Multicast Between Layer 2 and Layer 3 Devices Using Snooping
- play_arrow Configure Multicast Routing Options
- play_arrow Controller-Based BGP Multicast Signaling
  - Controller-Based BGP Multicast Signaling
play_arrow Troubleshooting
- play_arrow Knowledge Base
  - Knowledge Search
  - JTAC Certified Step-by-Step Troubleshooting: Junos OS Multicast
play_arrow Configuration Statements and Operational Commands
- Junos CLI Reference Overview

list Table of Contents

English

Example: Configuring Multicast-Only Fast Reroute in a PIM Domain

date_range 23-Nov-23

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This example shows how to configure multicast-only fast reroute (MoFRR) to minimize packet loss in a network when there is a link failure. It works by enhancing the multicast routing protocol, Protocol Independent Multicast (PIM).

MoFRR transmits a multicast join message from a receiver toward a source on a primary path, while also transmitting a secondary multicast join message from the receiver toward the source on a backup path. Data packets are received from both the primary path and the backup paths. The redundant packets are discarded at topology merge points , based on priority (weights assigned to primary and backup paths). When a failure is detected on the primary path, the repair is made by changing the interface on which packets are accepted to the secondary interface. Because the repair is local, it is fast—greatly improving convergence times in the event of a link failure on the primary path.

Requirements

No special configuration beyond device initialization is required before configuring this example.

In this example, only the egress provider edge (PE) router has MoFRR enabled,MoFRR in a PIM domain can be enabled on any of the routers.

MoFRR is supported on MX Series platforms with MPC line cards. As a prerequisite, the router must be set to network-services enhanced-ip mode, and all the line-cards in the platform must be MPCs.

This example requires Junos OS Release 14.1 or later on the egress PE router.

Overview

In this example, Device R3 is the egress edge router. MoFRR is enabled on this device only.

OSPF or IS-IS is used for connectivity, though any interior gateway protocol (IGP) or static routes can be used.

PIM sparse mode version 2 is enabled on all devices in the PIM domain. Device R1 serves as the rendezvous point (RP).

Device R3, in addition to MoFRR, also has PIM join load balancing enabled.

For testing purposes, routers are used to simulate the source and the receiver. Device R3 is configured to statically join the desired group by using the set protocols igmp interface fe-1/2/15.0 static group 225.1.1.1 command. It is just joining, not listening. The fe-1/2/15.0 interface is the Device R3 interface facing the receiver. In the case when a real multicast receiver host is not available, as in this example, this static IGMP configuration is useful. On the receiver, to make it listen to the multicast group address, this example uses set protocols sap listen 225.1.1.1. To make the source send multicast traffic, a multicast ping is issued from the source router. The ping command is ping 225.1.1.1 bypass-routing interface fe-1/2/10.0 ttl 10 count 1000000000. The fe-1/2/10.0 interface is the source interface facing Device R1.

MoFRR configuration includes multiple options that are not shown in this example, but are explained separately. The options are as follows:

stream-protection {
    mofrr-asm-starg;
    mofrr-disjoint-upstream-only;
    mofrr-no-backup-join;
    mofrr-primary-path-selection-by-routing;
    policy policy-name; 
}

Topology

Figure 1 shows the sample network.

Figure 1: MoFRR in a PIM Domain

CLI Quick Configuration shows the configuration for all of the devices in Figure 1.

The section Step-by-Step Configuration describes the steps on Device R3.

CLI Quick Configuration

To quickly configure this example, copy the following commands, paste them into a text file, remove any line breaks, change any details necessary to match your network configuration, and then copy and paste the commands into the CLI at the [edit] hierarchy level.

Device R1

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set interfaces fe-1/2/10 unit 0 family inet address 10.0.0.2/30
set interfaces fe-1/2/11 unit 0 family inet address 10.0.0.5/30
set interfaces fe-1/2/12 unit 0 family inet address 10.0.0.17/30
set interfaces lo0 unit 0 family inet address 192.168.0.1/32
set protocols ospf area 0.0.0.0 interface fe-1/2/10.0
set protocols ospf area 0.0.0.0 interface fe-1/2/11.0
set protocols ospf area 0.0.0.0 interface lo0.0 passive
set protocols ospf area 0.0.0.0 interface fe-1/2/12.0
set protocols pim rp local family inet address 192.168.0.1
set protocols pim interface all mode sparse
set protocols pim interface all version 2

Device R2

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set interfaces fe-1/2/11 unit 0 family inet address 10.0.0.6/30
set interfaces fe-1/2/13 unit 0 family inet address 10.0.0.9/30
set interfaces lo0 unit 0 family inet address 192.168.0.2/32
set protocols ospf area 0.0.0.0 interface fe-1/2/11.0
set protocols ospf area 0.0.0.0 interface fe-1/2/13.0
set protocols ospf area 0.0.0.0 interface lo0.0 passive
set protocols pim rp static address 192.168.0.1
set protocols pim interface all mode sparse
set protocols pim interface all version 2

Device R3

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set chassis network-services enhanced-ip
set interfaces fe-1/2/13 unit 0 family inet address 10.0.0.10/30
set interfaces fe-1/2/15 unit 0 family inet address 10.0.0.13/30
set interfaces fe-1/2/14 unit 0 family inet address 10.0.0.22/30
set interfaces lo0 unit 0 family inet address 192.168.0.3/32
set protocols igmp interface fe-1/2/15.0 static group 225.1.1.1
set protocols ospf area 0.0.0.0 interface fe-1/2/13.0
set protocols ospf area 0.0.0.0 interface fe-1/2/15.0
set protocols ospf area 0.0.0.0 interface lo0.0 passive
set protocols ospf area 0.0.0.0 interface fe-1/2/14.0
set protocols pim rp static address 192.168.0.1
set protocols pim interface all mode sparse
set protocols pim interface all version 2
set protocols pim join-load-balance automatic
set policy-options policy-statement load-balancing-policy then load-balance per-packet
set routing-options forwarding-table export load-balancing-policy
set routing-options multicast stream-protection

Device R6

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set interfaces fe-1/2/12 unit 0 family inet address 10.0.0.18/30
set interfaces fe-1/2/14 unit 0 family inet address 10.0.0.21/30
set interfaces lo0 unit 0 family inet address 192.168.0.6/32
set protocols ospf area 0.0.0.0 interface fe-1/2/12.0
set protocols ospf area 0.0.0.0 interface fe-1/2/14.0
set protocols ospf area 0.0.0.0 interface lo0.0 passive
set protocols pim rp static address 192.168.0.1
set protocols pim interface all mode sparse
set protocols pim interface all version 2

Device Source

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set interfaces fe-1/2/10 unit 0 family inet address 10.0.0.1/30
set interfaces lo0 unit 0 family inet address 192.168.0.4/32
set protocols ospf area 0.0.0.0 interface fe-1/2/10.0
set protocols ospf area 0.0.0.0 interface lo0.0 passive

Device Receiver

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set interfaces fe-1/2/15 unit 0 family inet address 10.0.0.14/30
set interfaces lo0 unit 0 family inet address 192.168.0.5/32
set protocols sap listen 225.1.1.1
set protocols ospf area 0.0.0.0 interface fe-1/2/15.0
set protocols ospf area 0.0.0.0 interface lo0.0 passive

Step-by-Step Configuration

Step-by-Step Procedure

The following example requires that you navigate various levels in the configuration hierarchy. For information about navigating the CLI, see Using the CLI Editor in Configuration Mode in the Junos OS CLI User Guide.

To configure Device R3:

Enable enhanced IP mode.

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[edit chassis]
user@R3# set network-services enhanced-ip

Configure the device interfaces.

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[edit interfaces]
user@R3# set fe-1/2/13 unit 0 family inet address 10.0.0.10/30
user@R3# set fe-1/2/15 unit 0 family inet address 10.0.0.13/30
user@R3# set fe-1/2/14 unit 0 family inet address 10.0.0.22/30
user@R3# set lo0 unit 0 family inet address 192.168.0.3/32

For testing purposes only, on the interface facing Device Receiver, simulate IGMP joins.

If your test environment has receiver hosts, this step is not necessary.
```
[edit protocols igmp interface fe-1/2/15.0]
user@R3# set static group 225.1.1.1
```

Configure an IGP or static routes.

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[edit protocols ospf area 0.0.0.0]
user@R3# set interface fe-1/2/13.0
user@R3# set interface fe-1/2/15.0
user@R3# set interface lo0.0 passive
user@R3# set interface fe-1/2/14.0

Configure PIM.

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[edit protocols pim]
user@R3# set rp static address 192.168.0.1
user@R3# set interface all mode sparse
user@R3# set interface all version 2

(Optional) Configure PIM join load balancing.
```
[edit protocols pim]
user@R3# set join-load-balance automatic
```

(Optional) Configure per-packet load balancing.

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[edit policy-options policy-statement load-balancing-policy]
user@R3# set then load-balance per-packet
[edit routing-options forwarding-table]
user@R3# set export load-balancing-policy

Enable MoFRR.

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[edit routing-options multicast]
user@R3# set stream-protection

Results

From configuration mode, confirm your configuration by entering the show chassis, show interfaces, show protocols, show policy-options, and show routing-options commands. If the output does not display the intended configuration, repeat the instructions in this example to correct the configuration.

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user@R3# show chassis
network-services enhanced-ip;

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user@R3# show interfaces
fe-1/2/13 {
    unit 0 {
        family inet {
            address 10.0.0.10/30;
        }
    }
}
fe-1/2/14 {
    unit 0 {
        family inet {
            address 10.0.0.22/30;
        }
    }
}
fe-1/2/15 {
    unit 0 {
        family inet {
            address 10.0.0.13/30;
        }
    }
}
lo0 {
    unit 0 {
        family inet {
            address 192.168.0.3/32;
        }
    }
}

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user@R3# show protocols
igmp {
    interface fe-1/2/15.0 {
        static {
            group 225.1.1.1;
        }
    }
}
ospf {
    area 0.0.0.0 {
        interface fe-1/2/13.0;
        interface fe-1/2/15.0;
        interface lo0.0 {
            passive;
        }
        interface fe-1/2/14.0;
    }
}
pim {
    rp {
        static {
            address 192.168.0.1;
        }
    }
    interface all {
        mode sparse;
        version 2;
    }
    join-load-balance {
        automatic;
    }
}

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user@R3# show policy-options
policy-statement load-balancing-policy {
    then {
        load-balance per-packet;
    }
}

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user@R3# show routing-options
forwarding-table {
    export load-balancing-policy;
}
multicast {
    stream-protection;
}

If you are done configuring the device, enter commit from configuration mode.

Verification

Confirm that the configuration is working properly.

Sending Multicast Traffic Into the PIM Domain
Verifying the Upstream Interfaces
Checking the Multicast Routes

Sending Multicast Traffic Into the PIM Domain

Purpose
Action
Meaning

Purpose

Use a multicast ping command to simulate multicast traffic.

Action

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user@Source> ping 225.1.1.1 bypass-routing interface fe-1/2/10.0 ttl 10 count 1000000000

PING 225.1.1.1 (225.1.1.1): 56 data bytes
64 bytes from 10.0.0.14: icmp_seq=1 ttl=61 time=0.845 ms
64 bytes from 10.0.0.14: icmp_seq=2 ttl=61 time=0.661 ms
64 bytes from 10.0.0.14: icmp_seq=3 ttl=61 time=0.615 ms
64 bytes from 10.0.0.14: icmp_seq=4 ttl=61 time=0.640 ms

Meaning

The interface on Device Source, facing Device R1, is fe-1/2/10.0. Keep in mind that multicast pings have a TTL of 1 by default, so you must use the ttl option.

Verifying the Upstream Interfaces

Purpose
Action
Meaning

Purpose

Make sure that the egress device has two upstream interfaces for the multicast group join.

Action

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user@R3> show pim join 225.1.1.1 extensive sg
Instance: PIM.master Family: INET
R = Rendezvous Point Tree, S = Sparse, W = Wildcard

Group: 225.1.1.1
    Source: 10.0.0.1
    Flags: sparse,spt
    Active upstream interface: fe-1/2/13.0
    Active upstream neighbor: 10.0.0.9
    MoFRR Backup upstream interface: fe-1/2/14.0
    MoFRR Backup upstream neighbor: 10.0.0.21
    Upstream state: Join to Source, No Prune to RP
    Keepalive timeout: 354
    Uptime: 00:00:06 
    Downstream neighbors:
        Interface: fe-1/2/15.0           
            10.0.0.13 State: Join Flags: S   Timeout: Infinity
            Uptime: 00:00:06 Time since last Join: 00:00:06
    Number of downstream interfaces: 1

Meaning

The output shows an active upstream interface and neighbor, and also an MoFRR backup upstream interface and neighbor.

Checking the Multicast Routes

Purpose
Action
Meaning

Purpose

Examine the IP multicast forwarding table to make sure that there is an upstream RPF interface list, with a primary and a backup interface.

Action

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user@R3> show multicast route extensive

Instance: master Family: INET

Group: 225.1.1.1
    Source: 10.0.0.1/32
    Upstream rpf interface list: 
        fe-1/2/13.0 (P) fe-1/2/14.0 (B)
    Downstream interface list: 
        fe-1/2/15.0
    Session description: Unknown
    Forwarding statistics are not available
    RPF Next-hop ID: 836
    Next-hop ID: 1048585
    Upstream protocol: PIM
    Route state: Active
    Forwarding state: Forwarding
    Cache lifetime/timeout: 171 seconds
    Wrong incoming interface notifications: 0
    Uptime: 00:03:09

Meaning

The output shows an upstream RPF interface list, with a primary and a backup interface.

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Example: Configuring Multicast-Only Fast Reroute in a PIM Domain

Requirements

Overview

Topology

CLI Quick Configuration

CLI Quick Configuration

Step-by-Step Configuration

Procedure

Step-by-Step Procedure

Results

Verification

Sending Multicast Traffic Into the PIM Domain

Purpose

Action

Meaning

Verifying the Upstream Interfaces

Purpose

Action

Meaning

Checking the Multicast Routes

Purpose

Action

Meaning

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Multicast Protocols User Guide

ON THIS PAGE

Example: Configuring Multicast-Only Fast Reroute in a PIM Domain

Requirements

Overview

Topology

CLI Quick Configuration

CLI Quick Configuration

Step-by-Step Configuration

Procedure

Step-by-Step Procedure

Results

Verification

Sending Multicast Traffic Into the PIM Domain

Purpose

Action

Meaning

Verifying the Upstream Interfaces

Purpose

Action

Meaning

Checking the Multicast Routes

Purpose

Action

Meaning

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