Routing Configuration Guide, Cisco Catalyst SD-WAN Releases 17.x

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Multicast overlay routing for Cisco IOS XE Catalyst SD-WAN

Updated: February 6, 2026

Overview

This overview explains how the system optimizes distribution trees and uses OMP to manage receiver interest and dynamic join/prune actions.

A Cisco IOS XE Catalyst SD-WAN multicast overlay is a routing protocol that:

  • extends Protocol Independent Multicast Source-Specific Multicast (PIM-SSM) over the Cisco Catalyst SD-WAN overlay using Overlay Management Protocol (OMP),

  • integrates PIM-SM in customer VPNs with OMP in the overlay, leverages Cisco IOS XE MVPN, and uses OMP replicators to optimize the multicast distribution tree across the overlay topology, and

  • supports IGMPv2 and IGMPv3 reports, advertising receiver multicast interest to remote Cisco Catalyst SD-WAN routers using OMP and enabling dynamic join or prune actions for optimized and secure multicast delivery over the overlay network.

The Cisco IOS XE Catalyst SD-WAN multicast overlay implementation extends native multicast by creating a secure optimized multicast tree that runs on top of the overlay network.

Protocol Independent Multicast Sparse-Mode (PIM-SM) is deployed in the customer VPNs, and the OMP replicator is used in overlay multicast to optimize the multicast distribution tree.

The Cisco IOS XE Catalyst SD-WAN router advertises receiver's multicast interest using OMP and participates in join or prune actions with replicators, which use OMP to relay these actions to routers providing overlay connectivity to the PIM-RP or source.

Multicast overlay supported features

Note

From Cisco IOS XE Catalyst SD-WAN Release 17.3.2, TLOC extension with multicast and multicast application-aware route policy features are supported.

  • IPv4 Overlay Multicast (PIM SSM), IPv4 Overlay Multicast (PIM ASM)

  • PIM-RP on IOS XE VPN

  • Replicator with geo-location (GPS)

  • Static RP and Auto-RP

  • PIM Bootstrap Router (BSR)

  • IGMP v2, IGMP v3, and PIM on service side

  • IPSec and GRE Encapsulation

  • vEdge and IOS XE Catalyst SD-WAN Interop

  • Overlay Multicast Signaling using OMP

Multicast overlay supported protocols

Restrictions for multicast overlay routing

Multicast overlay routing does not support these features:

  • MSDP/Anycast-RP on Cisco Catalyst SD-WAN routers.

  • IPv6 overlay and IPv6 underlay.

  • Dynamic BFD tunnel for multicast.

  • Multicast with asymmetric unicast routing.

  • Multicast overlay working does not support Data Policy. If a data policy is configured, only the required traffic is matched and multicast traffic is not matched.

  • The Cisco vEdge device is used only as the Last Hop Router (LHR), whereas Cisco IOS XE Catalyst SD-WAN devices can be used in all multicast roles (FHR, LHR, RP and Replicator roles).

  • Bidirectional PIM is not supported with hub-and-spoke or full-mesh deployments.

  • On Cisco 1000 Series Integrated Services Routers, when IGMP snooping is enabled and there are no local receivers for multicast traffic in the VLAN, the multicast traffic floods to all ports in the VLAN.

Restrictions for multicast routing with hub-and-spoke topology

Minimum supported releases: Cisco IOS XE Catalyst SD-WAN Release 17.15.1a and Cisco Catalyst SD-WAN Manager Release 20.15.1.

  • You can configure multicast rendezvous point and replicator node on hub-site devices only. Replicator cannot be configured on spoke-site devices.

  • MSDP interconnect feature is not supported with hub-and-spoke multicast deployment.

  • You can configure multicast routing on hub-and-spoke using CLI add-on template only.

  • On-demand tunnel between spoke sites is not supported with multicast.

  • Multicast is supported only with centralized control policy–based hub-and-spoke deployment. Intent-based configuration, as described in the Hub-and-Spoke chapter, is not supported.