1-17IGMP Snooping Configuration ExamplesConfiguring IGMP SnoopingNetwork requirementsTo prevent multicast traffic from being flooded at Layer 2, enable IGMP snooping on Layer 2 switches.z As shown in Figure 3-3, Router A connects to a multicast source (Source) through Ethernet 1/0/2,and to Switch A through Ethernet 1/0/1.z Run PIM-DM and IGMP on Router A. Run IGMP snooping on Switch A. Router A acts as the IGMPquerier.z The multicast source sends multicast data to the multicast group 224.1.1.1. Host A and Host B arereceivers of the multicast group 224.1.1.1.Network diagramFigure 3-3 Network diagram for IGMP Snooping configurationMulticast packetsSourceRouter A Switch AReceiverReceiverHost BHost AHost C1.1.1.1/24Eth1/0/4Eth1/0/2Eth1/0/3IGMP querierEth1/0/1Eth1/0/110.1.1.1/24Eth1/0/21.1.1.2/24VLAN100Configuration procedure1) Configure the IP address of each interfaceConfigure an IP address and subnet mask for each interface as per Figure 3-3. The detailedconfiguration steps are omitted.2) Configure Router A# Enable IP multicast routing, enable PIM-DM on each interface, and enable IGMP on Ethernet 1/0/1. system-view[RouterA] multicast routing-enable[RouterA] interface Ethernet 1/0/1[RouterA-Ethernet1/0/1] igmp enable[RouterA-Ethernet1/0/1] pim dm[RouterA-Ethernet1/0/1] quit[RouterA] interface Ethernet 1/0/2[RouterA-Ethernet1/0/2] pim dm[RouterA-Ethernet1/0/2] quit
