Cisco Nexus 6000 Series - Configuring IGMP Snooping; Information About IGMP Snooping

CHAPTER 10
Configuring IGMP Snooping
This chapter contains the following sections:
•
Information About IGMP Snooping, page 117
•
Configuring IGMP Snooping Parameters, page 120
•
Verifying the IGMP Snooping Configuration, page 122
Information About IGMP Snooping
The IGMP snooping software examines IGMP protocol messages within a VLAN to discover which interfaces
are connected to hosts or other devices interested in receiving this traffic. Using the interface information,
IGMP snooping can reduce bandwidth consumption in a multiaccess LAN environment to avoid flooding the
entire VLAN. The IGMP snooping feature tracks which ports are attached to multicast-capable routers to help
it manage the forwarding of IGMP membership reports. The IGMP snooping software responds to topology
change notifications.
IGMP snooping is supported on all Ethernet interfaces. The term snooping is used because Layer 3 control
plane packets are intercepted and influence Layer 2 forwarding decisions.
Note
Cisco NX-OS supports IGMPv2 and IGMPv3. IGMPv2 supports IGMPv1, and IGMPv3 supports IGMPv2.
Although not all features of an earlier version of IGMP are supported, the features related to membership
query and membership report messages are supported for all IGMP versions.
Cisco Nexus 6000 Series NX-OS Layer 2 Switching Configuration Guide, Release 7.x
117