Configuring IGMP Snooping

This chapter contains these sections:

Configuring IGMP Snooping Over VXLAN

IGMP snooping mechanisms over VXLAN

IGMP snooping mechanisms over VXLAN are multicast traffic management features that

  • enable each VTEP to monitor IGMP reports sent within VXLAN segments,

  • selectively forward multicast traffic only to interested receivers, and

  • reduce unnecessary flooding of multicast traffic in the VNI/VLAN.

The configuration of IGMP snooping in VXLAN is the same as in a regular VLAN domain.

For further information, see:

Guidelines for IGMP snooping over VXLAN

  • Do not configure IGMP snooping over VXLAN on VLANs with FEX member ports.

  • You can configure IGMP snooping over VXLAN with both IR and multicast underlay.

  • Use IGMP snooping over VXLAN in BGP EVPN topologies, not in flood and learn topologies.

  • Beginning with NX-OS release 9.3(3), you can configure IGMP snooping over VXLAN on Cisco Nexus 9300-GX switches.

Configure IGMP snooping over VXLAN

IGMP snooping over VXLAN ensures optimized multicast traffic forwarding by delivering packets only to receivers that have joined the group, reducing unnecessary flooding in the data center fabric.

Before you begin

  • You have access to the device CLI in privileged EXEC mode.

  • VXLAN and VLANs are already configured on the switch.

Procedure

Step 1

Enter global configuration mode.

Example:

switch# configure terminal

This mode allows you to configure system-wide settings.

Step 2

Enable IGMP snooping for VXLAN VLANs.

Example:

switch(config)# ip igmp snooping vxlan

This command is required to activate snooping on VXLAN-enabled VLANs.

Step 3

(Optional) Prevent the NVE interface from acting as a static mrouter port.

Example:

switch(config)# ip igmp snooping disable-nve-static-router-port

By default, IGMP snooping over VXLAN adds the NVE interface as a multicast router port.

Note

 

This command is not required for TRM-based VXLAN EVPN fabrics. Enabling it may cause multicast forwarding issues in TRM fabrics.

IGMP snooping is enabled for VXLAN VLANs as configured.