Cisco ASR 9000 Series User manual

Cisco ASR 9000 Series Aggregation Services Router Multicast
Configuration Guide, Release 6.0.x
First Published: 2016-05-06
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CONTENTS
Preface Preface xiii
Changes to This Document xiii
Obtaining Documentation and Submitting a Service Request xiii
CHAPTER 1 New and Changed Multicast Features 1
New and Changed Multicast Features 1
New and Changed Multicast Features 1
CHAPTER 2 Implementing Layer-2 Multicast with IGMP Snooping 3
Prerequisites for IGMP Snooping 4
Restrictions for IGMP Snooping 4
Information About IGMP Snooping 4
IGMP Snooping Overview 4
Description of Basic Functions 4
High Availability Features 5
Bridge Domain Support 5
Multicast Router and Host Ports 5
Multicast Router Discovery and Static Configuration 6
Multicast Traffic Handling within a Bridge Domain with IGMP Snooping Enabled 6
Multichassis Link Aggregation 8
Bidirectional Internet Group Management Protocol Snoop Synchronization for Satellite
Dual-Homed System 8
Restrictions 9
Information About IGMP Snooping Configuration Profiles 9
Creating Profiles 10
Attaching and Detaching Profiles 10
Changing Profiles 10
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Configuring Access Control 10
Default IGMP Snooping Configuration Settings 12
IGMP Snooping Configuration at the Bridge Domain Level 13
IGMP Minimum Version 13
System IP Address 13
Group Membership Interval, Robustness Variable, and Query Interval 13
Report Suppression (IGMPv2) and Proxy Reporting (IGMPv3) 14
Group Leave Processing 14
Reaction to Topology Change Notifications 16
IGMP Snooping Packet Checks 17
Startup Query Configuration 17
IGMP Snooping Configuration at the Host Port Level 18
Router Guard and Static Mrouter 18
Immediate-Leave 18
Static Groups 18
Internal Querier 19
When to Use an Internal Querier 19
Internal Querier Default Configuration 19
Internal Querier Processing 20
Querier Election for One Active Querier 20
Internal Querier Reaction to TCNs 21
How to Configure IGMP Snooping 21
Creating an IGMP Snooping Profile 21
Where to Go Next 22
Attaching a Profile and Activating IGMP Snooping on a Bridge Domain 22
Detaching a Profile and Deactivating IGMP Snooping on a Bridge Domain 24
Attaching and Detaching Profiles to Ports Under a Bridge 25
Adding Static Mrouter Configuration to a Profile 27
Where to Go Next 28
Adding Router Guard to a Profile 28
Where to Go Next 29
Configuring Immediate-Leave 30
Where to Go Next 31
Configuring Static Groups 31
Where to Go Next 32
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Configuring an Internal Querier 32
Where to Go Next 33
Verifying Multicast Forwarding 33
Configuring Group Limits 34
Configuring route-policy 34
Configuring group limit 35
Configuring access-groups 36
Configuration Examples for IGMP Snooping 37
Configuring IGMP Snooping on Physical Interfaces Under a Bridge: Example 37
Configuring IGMP Snooping on VLAN Interfaces Under a Bridge: Example 38
Configuring IGMP Snooping on Ethernet Bundles Under a Bridge: Example 38
Configuring IGMP Snooping on VFIs Under a Bridge: Example 40
Configuring IGMP access-groups 42
Configuring IGMP Snooping over MCLAG: Example 43
Case 1: Downstream MCLAG 43
Case 2 : Upstream MCLAG 48
Additional References 53
CHAPTER 3 Implementing MLD Snooping 55
MLD Snooping 56
Prerequisites for MLD Snooping 56
Restrictions for MLD Snooping 56
Advantages of MLD Snooping 56
High Availability (HA) features for MLD 57
Bridge Domain Support for MLD 57
Multicast Router and Host Ports 57
Multicast Router Discovery for MLD 58
Multicast Traffic Handling for MLD 58
Creating a MLD Snooping Profile 59
Activating MLD Snooping on a Bridge Domain 60
Deactivating MLD Snooping on a Bridge Domain 61
Configuring Static Mrouter Ports (MLD) 63
Configuring Router Guard (MLD) 63
Configuring Immediate-leave for MLD 65
Configuring Internal Querier for MLD 66
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Configuring Static Groups for MLD 67
Configuring MLD Snooping 68
Configuring MLD Snooping on Ethernet Bundles 68
CHAPTER 4 Implementing Layer-3 Multicast Routing on Cisco IOS XR Software 71
Prerequisites for Implementing Multicast Routing 73
Information About Implementing Multicast Routing 73
Key Protocols and Features Supported in the Cisco IOS XR Software Multicast Routing
Implementation 73
Multicast Routing Functional Overview 74
Multicast Routing Implementation 75
PIM-SM, PIM-SSM, and PIM-BIDIR 76
PIM-SM Operations 76
PIM-SSM Operations 77
PIM-Bidirectional Operations 77
Restrictions for PIM-SM and PIM-SSM, and PIM BIDIR 77
Internet Group Management Protocol 77
IGMP Versions 78
IGMP Routing Example 78
Configuring IGMP Per Interface States Limit 79
Protocol Independent Multicast 80
PIM-Sparse Mode 81
PIM-Source Specific Multicast 81
DNS-based SSM Mapping 81
PIM-Bidirectional Mode 83
Configuring PIM Per Interface States Limit 84
PIM Shared Tree and Source Tree (Shortest Path Tree) 85
Multicast-Intact 86
Designated Routers 87
Rendezvous Points 88
Auto-RP 89
PIM Bootstrap Router 90
Reverse-Path Forwarding 90
Multicast Non-Stop Routing 90
Failure Scenarios in NSR 91
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Multicast VPN 91
Multicast VPN Routing and Forwarding 92
Multicast Distribution Tree Tunnels 92
InterAS Support on Multicast VPN 93
IPv6 Connectivity over MVPN 94
BGP Requirements 95
Segmented Multicast - Overview 95
Segmented Multicast - Examples 96
Segmented Multicast - Examples 97
Segmented Multicast Stitching with inter-AS Solution 99
Configuring Segmented Multicast Stitching 99
Configuration on a PE Router 100
Configuration on a ABR/ASBR 101
Multitopology Routing 101
Multicast VPN Extranet Routing 102
Information About Extranets 102
Information About the Extranet MVPN Routing Topology 103
RPF Policies in an Extranet 105
Multicast VPN Hub and Spoke Topology 105
Realizing the Hub and Spoke Topology 106
Label Switched Multicast (LSM) Multicast Label Distribution Protocol (mLDP) based Multicast
VPN (mVPN) Support 107
Benefits of LSM MLDP based MVPN 107
Configuring MLDP MVPN 107
P2MP and MP2MP Label Switched Paths 108
Packet Flow in mLDP-based Multicast VPN 109
Realizing a mLDP-based Multicast VPN 109
Characteristics of mLDP Profiles 109
Configuration rules for profiles 116
MLDP inband signaling 117
Summary of Supported MVPN Profiles 117
LSP-switch for P2MP-TE 118
Configuration Process for MLDP MVPN (Intranet) 118
MLDP Loop-Free Alternative Fast Reroute 120
Advantages of LFA FRR 122
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MLDP LFA FRR - Features 122
Limitations of LFA FRR 123
MLDP LFA FRR - Working 123
MLDP LFA FRR - Behavior 125
Configurations to Enable LFA FRR 126
Configuring Router OSPF LFA FRR 127
Enabling Per Prefix LFA 128
Adding Interfaces to LFA Candidate List 129
Exclude Interface from Backup 130
Restricting the Backup Interfaces to the LFA Candidate List 131
Limiting the Per-Prefix Calculation by Prefix-Priority 132
Disabling Load Sharing of the Backup Paths 133
Configuring Router ISIS LFA FRR 134
Configuring Bidirectional Forwarding Detection 136
Configuring MPLS LFA FRR 140
Make Before Break Configuration for LFA FRR 141
Configuring Make Before Break Delay and Delete 143
Configuring FRR Time for Scalable Number of mLDP LSPs 145
MLDP Carrier Supporting Carrier Based MVPN 146
MLDP CsC - Restrictions 146
CsC Configuration Example - Overview 147
Configuration Changes for CsC 152
Configuration Changes for IGP for CsC 152
Configuration Changes for Supporting MLDP CsC 153
Configuration Changes for iBGP and eBGP for CsC 154
Configuration Changes for Multicast for CsC 156
Multipoint Label Distribution Protocol Route Policy Map 157
Configuring mLDP User Interface (Opaque Types) Using the Routing Policy 158
Configuring the mLDP User Interface for LDP Opaque Global ID Using the
Routing Policy 159
Configuring the mLDP User Interface for LDP Opaque IPv4 Using the Routing
Policy 160
Configuring the mLDP User Interface for LDP Opaque IPv6 Using the Routing
Policy 161
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Configuring the mLDP User Interface for LDP Opaque MDT Using the Routing
Policy 162
Configuring the mLDP User Interface for LDP Opaque Static ID Using the Routing
Policy 163
Configuring the mLDP User Interface for LDP Opaque Recursive Using the Routing
Policy 164
Configuring the mLDP User Interface for LDP Opaque Recursive-RD Using the
Routing Policy 165
Configuring the mLDP User Interface for LDP Opaque VPNv4 Using the Routing
Policy 166
Configuring the mLDP User Interface for LDP Opaque VPNv6 Using the Routing
Policy 167
Configuring mLDP FEC at the Root Node 168
Configuring the mLDP FEC at the Root Node Using the Route Policy 168
Configuring the mLDP User Interface to Filter Label Mappings 169
Configuring the mLDP User Interface to Filter Label Mappings 170
Configuring the mLDP User Interface for Feature Filtering 171
Configuring the mLDP User Interface for Feature Filtering - MoFRR 171
Configuring the mLDP User Interface for Feature Filtering - Make-before-break 172
Configuring the mLDP User Interface for Feature Filtering - Recursive FEC 174
Limitations of Route Policy Map 175
Next-Generation Multicast VPN 176
Supported Features 176
PE-PE Ingress Replication 179
MVPN over GRE 179
Native Multicast 180
GRE Limitations 181
Signaling and RPF on GRE Tunnels 182
PIM Registration 182
Auto-RP 182
Multicast IRB 183
Supported bridge port types 183
Restrictions 183
Multicast IRB 183
Multicast support for PW-HE interfaces 183
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Multicast Source Discovery Protocol 184
VRF-aware MSDP 184
Multicast Nonstop Forwarding 184
Multicast Configuration Submodes 185
Multicast-Routing Configuration Submode 185
PIM Configuration Submode 185
IGMP Configuration Submode 186
MLD Configuration Submode 186
MSDP Configuration Submode 186
Understanding Interface Configuration Inheritance 186
Understanding Interface Configuration Inheritance Disablement 187
Understanding Enabling and Disabling Interfaces 187
Multicast Routing Information Base 188
Multicast Forwarding Information Base 188
MSDP MD5 Password Authentication 188
Overriding VRFs in IGMP Interfaces 189
VRF support for MLD 189
How to Implement Multicast Routing 189
Configuring PIM-SM and PIM-SSM 190
Configuring PIM-SSM for Use in a Legacy Multicast Deployment 191
Restrictions for PIM-SSM Mapping 192
Configuring a Set of Access Control Lists for Static SSM Mapping 192
Configuring a Set of Sources for SSM Mapping 193
Configuring the DNS-based SSM Mapping 194
Configuring a Static RP and Allowing Backward Compatibility 195
Configuring Auto-RP to Automate Group-to-RP Mappings 196
Configuring the Bootstrap Router 198
Calculating Rates per Route 201
Configuring Multicast Nonstop Forwarding 203
Configuring Multicast VPN 205
Prerequisites for Multicast VPN 206
Restrictions for Multicast VPN for Multicast Routing 206
Enabling a VPN for Multicast Routing 207
Specifying the PIM VRF Instance 209
Specifying the IGMP VRF Instance 210
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Configuring the MDT Source per VRF 211
Configuring Label Switched Multicast 213
Verification of LSM mLDP based MVPN Configuration 218
Configuring Multitopology Routing 221
Restrictions for Configuring Multitopology Routing 221
Information About Multitopology Routing 222
Configuring an RPF Topology in PIM 222
Configuring MVPN Extranet Routing 224
Prerequisites for MVPN Extranet Routing 224
Restrictions for MVPN Extranet Routing 224
Configuring VPN Route Targets 225
Interconnecting PIM-SM Domains with MSDP 226
Controlling Source Information on MSDP Peer Routers 229
Configuring MSDP MD5 Password Authentication 231
Configuring VRF for MSDP 232
Multicast only fast reroute (MoFRR) 233
Operating Modes of MoFRR 233
Restrictions 234
Non-ECMP MoFRR 234
Implementing Non-ECMP MoFRR 234
Configuring MoFRR 235
RIB-based MoFRR 235
Flow-based MoFRR 236
Configuring Head PE Router (for MoFRR) 237
Configuring Tail PE Router (for MoFRR) 238
Enabling multicast on PW-HE interfaces 240
Static join 241
Configuring Route Policy for Static RPF 243
Point-to-Multipoint Traffic Engineering Label-Switched Multicast 244
Point to Multipoint LSP(P2MP) 244
Multicast Routing Protocol support for P2MP 245
Enabling Multicast Forwarding Over Tunnel Interface (at Ingress Node) 245
P2MP configurations at egress node and bud node 246
Configuring Static Reverse Path Forwarding (RPF) 246
Configuring Core Tree Protocol 247
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Configuring IGMP VRF Override 248
Specifying VRF definition 248
Enabling Multicast Routing on default and non-default VRFs 249
Configuring an Interface for a Non-default VRF Instance 250
Configuring route-policy 251
Associating a route policy to PIM configuration for the VRF receiving IGMP reports 252
Configuration Examples for Implementing Multicast Routing on Software 252
DNS-based SSM Mapping: Example 252
Calculating Rates per Route: Example 253
Preventing Auto-RP Messages from Being Forwarded on Software: Example 254
Inheritance in MSDP on Software: Example 254
MSDP-VRF: Example 255
MoFRR Provider Edge Configuration: Example 256
Configuring Route Policy for Static RPF: Example 256
Configuring IPv4 Multicast VPN: Example 256
Configuring MVPN to Advertise Routes Between the CE and the PE Using OSPF:
Example 256
Configuring MVPN to Advertise Routes Between the CE and the PE Using BGP:
Example 261
Configuration Examples for MVPN Profiles 265
Configuration Examples for Inband mLDP profiles 265
Configuration Examples for P2MP-TE profiles 266
Configuration examples for Partitioned mLDP profiles 268
Configuration Examples for Rosen-mGRE profiles 271
Configuration Examples for Rosen mLDP profiles 272
Configuration Examples for multicast support on PW-HE 275
Configuring MVPN Extranet Routing: Example 276
Configuring the Source MVRF on the Receiver PE Router: Example 276
Configuring the Receiver MVRF on the Source PE Router: Example 278
Configuring Multicast Hub and Spoke Topology: Example 281
Hub and Spoke Non-Turnaround Configuration: Example 281
Hub and Spoke with Turnaround: Example 289
Configuring LSM based MLDP: Examples 296
Additional References 306
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Preface
From Release 6.1.2 onwards, Cisco introduces support for the 64-bit Linux-based IOS XR operating system.
Extensive feature parity is maintained between the 32-bit and 64-bit environments. Unless explicitly marked
otherwise, the contents of this document are applicable for both the environments. For more details on Cisco
IOS XR 64 bit, refer to the Release Notes for Cisco ASR 9000 Series Routers, Release 6.1.2 document.
The preface contains these sections:
•Changes to This Document, page xiii
•Obtaining Documentation and Submitting a Service Request, page xiii
Changes to This Document
This table lists the technical changes made to this document since it was first released.
Table 1: Changes to This Document
SummaryDate
Initial release of this document for the 6.0.1 release.April 2016
Obtaining Documentation and Submitting a Service Request
For information on obtaining documentation, using the Cisco Bug Search Tool (BST), submitting a service
request, and gathering additional information, see What's New in Cisco Product Documentation.
To receive new and revised Cisco technical content directly to your desktop, you can subscribe to the What's
New in Cisco Product Documentation RSS feed. RSS feeds are a free service.
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Preface
Obtaining Documentation and Submitting a Service Request

CHAPTER 1
New and Changed Multicast Features
This chapter lists all the features that have been added or modified in this guide. The table also contains
references to these feature documentation sections.
•New and Changed Multicast Features, page 1
•New and Changed Multicast Features, page 1
New and Changed Multicast Features
This table summarizes the new and changed information for Multicast Configuration Guide and provide
information on where they are documented in the guide.
Table 2: New and Changed Multicast Feature Information
Where DocumentedChanged in ReleaseDescriptionFeature
Segmented Multicast -
Overview, on page 95
Release 6.0.1This feature was introduced.Segmented Multicast Stitching
with inter AS
MLDP Carrier Supporting
Carrier Based MVPN, on page
146
Release 6.0.1This feature was introduced.MLDP Carrier Supporting
Carrier Based MVPN
New and Changed Multicast Features
This table summarizes the new and changed information for Multicast Configuration Guide and provide
information on where they are documented in the guide.
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Table 3: New and Changed Multicast Feature Information
Where DocumentedChanged in ReleaseDescriptionFeature
Segmented Multicast -
Overview, on page 95
Release 6.0.1This feature was introduced.Segmented Multicast Stitching
with inter AS
MLDP Carrier Supporting
Carrier Based MVPN, on page
146
Release 6.0.1This feature was introduced.MLDP Carrier Supporting
Carrier Based MVPN
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New and Changed Multicast Features
New and Changed Multicast Features

CHAPTER 2
Implementing Layer-2 Multicast with IGMP
Snooping
Internet Group Management Protocol (IGMP) snooping restricts multicast flows at Layer 2 to only those
segments with at least one interested receiver. This module describes how to implement IGMP snooping on
Cisco ASR 9000 Series Routers.
Feature History for IGMP Snooping
ModificationRelease
This feature was introduced.Release 3.7.2
Support was added for the following features:
•IGMP snooping group limits and access groups.
Release 3.9.2
Support was added for the following features:
•Multicast redundancy using Multi-Chassis Link
Aggregation (MC-LAG).
Release 4.0.0
•Prerequisites for IGMP Snooping, page 4
•Restrictions for IGMP Snooping, page 4
•Information About IGMP Snooping, page 4
•How to Configure IGMP Snooping, page 21
•Configuration Examples for IGMP Snooping, page 37
•Additional References, page 53
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Prerequisites for IGMP Snooping
The following prerequisites must be satisfied before implementing IGMP snooping:
•The network must be configured with a Layer 2 VPN (L2VPN).
•You must be in a user group associated with a task group that includes the proper task IDs. The command
reference guides include the task IDs required for each command. If you suspect user group assignment
is preventing you from using a command, contact your AAA administrator for assistance.
To use this command, you must be in a user group associated with a task group that includes appropriate
task IDs. If the user group assignment is preventing you from using a command, contact your AAA
administrator for assistance.
Restrictions for IGMP Snooping
•IGMP snooping is supported only under L2VPN bridge domains.
•Explicit host tracking (an IGMPv3 snooping feature) is not supported.
•IPv6 Multicast Listener Discovery (MLD) snooping is not supported.
•IGMPv1 is not supported.
Information About IGMP Snooping
IGMP Snooping Overview
Description of Basic Functions
IGMP snooping provides a way to constrain multicast traffic at Layer 2. By snooping the IGMP membership
reports sent by hosts in the bridge domain, the IGMP snooping application can set up Layer 2 multicast
forwarding tables to deliver traffic only to ports with at least one interested member, significantly reducing
the volume of multicast traffic.
Configured at Layer 3, IGMP provides a means for hosts in an IPv4 multicast network to indicate which
multicast traffic they are interested in and for routers to control and limit the flow of multicast traffic in the
network at Layer 3.
IGMP snooping uses the information in IGMP membership report messages to build corresponding information
in the forwarding tables to restrict IP multicast traffic at Layer 2. The forwarding table entries are in the form
<Route, OIF List>, where:
•Route is a <*, G> route or <S, G> route.
•OIF List comprises all bridge ports that have sent IGMP membership reports for the specified route plus
all multicast router (mrouter) ports in the bridge domain.
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Prerequisites for IGMP Snooping

Implemented in a multicast network, IGMP snooping has the following attributes:
•In its basic form, it reduces bandwidth consumption by reducing multicast traffic that would otherwise
flood an entire VPLS bridge domain.
•With the use of some optional configurations, it provides security between bridge domains by filtering
the IGMP reports received from hosts on one bridge port and preventing leakage towards the hosts on
other bridge ports.
•Using optional configurations, reduces the traffic impact on upstream IP multicast routers by suppressing
IGMP membership reports (IGMPv2) or by acting as an IGMP proxy reporter (IGMPv3) to the upstream
IP multicast router.
High Availability Features
All high availability features apply to the IGMP snooping processes with no additional configuration beyond
enabling IGMP snooping. The following high availability features are supported:
•Process restarts
•RP Failover
•Stateful Switch-Over (SSO)
•Non-Stop Forwarding (NSF)—Forwarding continues unaffected while the control plane is restored
following a process restart or route processor (RP) failover.
•Line card online insertion and removal (OIR)
Bridge Domain Support
IGMP snooping operates at the bridge domain level. When IGMP snooping is enabled on a bridge domain,
the snooping functionality applies to all ports under the bridge domain, including:
•Physical ports under the bridge domain.
•Ethernet flow points (EFPs)—An EFP can be a VLAN, VLAN range, list of VLANs, or an entire interface
port.
•Pseudowires (PWs) in VPLS bridge domains.
•Ethernet bundles—Ethernet bundles include IEEE 802.3ad link bundles and Cisco EtherChannel bundles.
From the perspective of the IGMP snooping application, an Ethernet bundle is just another EFP. The
forwarding application in the Cisco ASR 9000 Series Routers randomly nominates a single port from
the bundle to carry the multicast traffic.
Multicast Router and Host Ports
IGMP snooping classifies each port (for example, EFPs, PWs, physical ports, or EFP bundles) as one of the
following:
•Multicast router ports (mrouter ports)—These are ports to which a multicast-enabled router is connected.
Mrouter ports are usually dynamically discovered, but may also be statically configured. Multicast traffic
is always forwarded to all mrouter ports, except when an mrouter port is the ingress port.
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Implementing Layer-2 Multicast with IGMP Snooping
IGMP Snooping Overview

•Host ports—Any port that is not an mrouter port is a host port.
Multicast Router Discovery and Static Configuration
IGMP snooping discovers mrouter ports dynamically. You can also explicitly configure a port as an mrouter
port.
•Discovery—IGMP snooping identifies upstream mrouter ports in the bridge domain by snooping IGMP
query messages and Protocol Independent Multicast Version 2 (PIMv2) hello messages. Snooping PIMv2
hello messages identifies IGMP nonqueriers in the bridge domain.
•Static configuration—You can statically configure a port as an mrouter port with the mrouter command
in a profile attached to the port. Static configuration can help in situations when incompatibilities with
non-Cisco equipment prevent dynamic discovery.
The router-guard command prevents a port from becoming a dynamically discovered mrouter port by filtering
out multicast router messages, including IGMP queries and PIM messages. You can configure a port with the
router-guard command and then configure it as a static mrouter. See the Router Guard and Static Mrouter,
on page 18 for more information about configuring router-guard and mrouter commands on the same port.
Multicast Traffic Handling within a Bridge Domain with IGMP Snooping Enabled
The following tables describe traffic handling behaviors by IGMP snooping mrouter and host ports. Table 4:
Multicast Traffic Handling for an IGMPv2 Querier, on page 6 describes traffic handling for an IGMPv2
querier. Table 5: Multicast Traffic Handling for an IGMPv3 Querier, on page 7 applies to an IGMPv3
querier.
By default, IGMP snooping supports IGMPv2 and IGMPv3. The version of the IGMP querier discovered in
the bridge domain determines the operational version of the snooping processes. If you change the default,
configuring IGMP snooping to support a minimum version of IGMPv3, IGMP snooping ignores any IGMPv2
queriers.
Table 4: Multicast Traffic Handling for an IGMPv2 Querier
Received on Host PortsReceived on MRouter PortsTraffic Type
Forwards to all mrouter ports and
to host ports that indicate interest.
Forwards to all mrouter ports and
to host ports that indicate interest.
IP multicast source traffic
—
Forwards to all ports.IGMP general queries
DroppedForwards to all other mrouter ports.IGMP group-specific queries
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IGMP Snooping Overview