H3C Technologies H3C S3100 Series Switches - Manual (Page 297)

2-10
Operation Command Remarks
Enable IGMP Snooping igmp-snooping enable
Required
By default, IGMP Snooping is
disabled.
Enter VLAN view vlan vlan-id —
Enable IGMP Snooping igmp-snooping enable
Required
By default, IGMP Snooping is
disabled.
Enable IGMP Snooping querier igmp-snooping querier
Required
By default, IGMP Snooping querier
is disabled.
Configuring IGMP query interval
Follow these steps to configure IGMP query interval:
Operation Command Remarks
Enter system view system-view —
Enter VLAN view vlan vlan-id —
Configure the IGMP query interval
igmp-snooping query-interval
seconds Optional
60 seconds by default.
Configuring the source address to be carried in IGMP queries
Follow these steps to configure the source address to be carried in IGMP queries:
Operation Command Remarks
Enter system view system-view —
Enter VLAN view vlan vlan-id —
Configure the source IP address of
IGMP general queries
igmp-snooping general-query
source-ip { current-interface |
ip-address }
Optional
0.0.0.0 by default
Configure the source IP address of
IGMP group-specific queries
igmp-snooping special-query
source-ip { current-interface |
ip-address }
0.0.0.0 by default
Suppressing Flooding of Unknown Multicast Traffic in a VLAN
With IGMP Snooping enabled in a VLAN, multicast traffic for unknown multicast groups is flooded within
the VLAN by default. This wastes network bandwidth and affects multicast forwarding efficiency.
With the unknown multicast flooding suppression function enabled, when receiving a multicast packet
for an unknown multicast group, an IGMP Snooping switch creates a nonflooding entry and relays the
packet to router ports only, instead of flooding the packet within the VLAN. If the switch has no router
ports, it drops the multicast packet.