17-4
Software Configuration Guide—Release 12.2(25)SG
OL-7659-03
Chapter17 Configuring IGMP Snooping and Filtering
Configuring IGMP Snooping
To determine whether or not EHT is enabled on a VLAN, use the show ip igmp snoop vlan command.
Configuring IGMP Snooping
Note When configuring IGMP, configure the VLAN in the VLAN database mode. (See Chapter 10,
“Understanding and 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 17-4
Enabling IGMP Snooping, page 17-5
Configuring Learning Methods, page 17-6
Configuring a Multicast Router Port Statical, page 17-7
Enabling IGMP Immediate-Leave Processing, page 17-7
Configuring Explicit Host Tracking, page 17-8
Configuring a Host Statically, page 17-8
Suppressing Multicast Flooding, page 17-9

Default IGMP Snooping Configuration

Table17-1 shows the IG MP snooping default configuration values.
Table17-1 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