23-5
Software Configuration Guide—Release 15.0(2)SG
OL-23818-01
Chapter 23 Configuring IGMP Snooping and Filtering Configuring IGMP Snooping
Configuring IGMP Snooping
Note When configuring IGMP, configure the VLAN in the VLAN database mode. See Chapter 13,
“Configuring VLANs, VTP, and VMPS.”
IGMP snooping allows switches to examine IGMP packets and make forwarding decisions based on their
content.
These sections describe how to configure IGMP snooping:
Default IGMP Snooping Configuration, page 23-5
Enabling IGMP Snooping Globally, page 23-6
Enabling IGMP Snooping on a VLAN, page 23-6
Configuring Learning Methods, page 23-7
Configuring a Static Connection to a Multicast Router, page 23-8
Enabling IGMP Immediate-Leave Processing, page 23-8
Configuring the IGMP Leave Timer, page 23-9
Configuring IGMP Snooping Querier, page 23-10
Configuring Explicit Host Tracking, page 23-11
Configuring a Host Statically, page 23-11
Suppressing Multicast Flooding, page 23-12

Default IGMP Snooping Configuration

Table 23-1 shows the IGMP snooping default configuration values.
Table 23-1 IGMP Snooping Default Configuration Values
Feature Default Value
IGMP snooping Enabled
Multicast routers None configured
Explicit Host Tracking Enabled for IGMPv3; Not available for IGMPv2
Immediate-leave processing Enabled for IGMPv3; Disabled for IGMPv2
Report Suppression Enabled
IGMP snooping learning method PIM/DVMRP1
1. PIM/DVMRP = Protocol Independent Multicast/Distance Vector Multicast Routing Protocol