Dell C1048P Port Extender Networking Configuration Guide for the C9000 Series - Page 453

IGMP version is 3 Dell(conf-if-te-1/13)# Viewing IGMP Groups To view both learned and statically configured IGMP groups, use the following command. • View both learned and statically configured IGMP groups. EXEC Privilege mode show ip igmp groups Example of the show ip igmp groups Command Dell#show ip igmp groups Total Number of Groups: 2 IGMP Connected Group Membership Group Address Interface Last Reporter 225.1.1.1 TenGigabitEthernet 1/0 1.1.1.2 225.1.1.2 TenGigabitEthernet 1/0 1.1.1.2 Mode Uptime Expires IGMPv2-Compat 00:00:06 00:02:03 IGMPv2-Compat 00:00:06 00:02:03 Enabling IGMP Immediate-Leave If the querier does not receive a response to a group-specific or group-and-source query, it sends another (querier robustness value). Then, after no response, it removes the group from the outgoing interface for the subnet. IGMP immediate leave reduces leave latency by enabling a router to immediately delete the group membership on an interface after receiving a Leave message (it does not send any group-specific or group-and-source queries before deleting the entry). • Configure the system for IGMP immediate leave. ip igmp immediate-leave • View the enable status of the IGMP immediate leave feature. EXEC Privilege mode show ip igmp interface View the enable status of this feature using the command from EXEC Privilege mode, as shown in the example in Selecting an IGMP Version. IGMP Snooping IGMP snooping enables switches to use information in IGMP packets to generate a forwarding table that associates ports with multicast groups so that when they receive multicast frames, they can forward them only to interested receivers. Multicast packets are addressed with multicast MAC addresses, which represent a group of devices, rather than one unique device. Switches forward multicast frames out of all ports in a virtual local area network (VLAN) by default, even though there may be only some interested hosts, which is a waste of bandwidth. Internet Group Management Protocol (IGMP) 453