3Com Switch 8800 Configuration Guide Chapter 24 IGMP Snooping Configuration
24-7
Caution:
If IGMP snooping is not enabled on the VLAN (nor Layer 3 multicast), unknown
multicast packets are broadcasted within the VLAN no matter whether this function is
enabled or not. That is, to make unknown multicast packets not be broadcasted with a
VLAN, you must enable igmp-snooping in this VLAN and enable igmp-snooping
nonflooding-enable globally.
Perform the following configuration in system view.
Table 24-5 Globally enable/disable multicast packets not broadcasted within a VLAN
Operation Command
Enable multicast packets not to be
broadcasted within a VLAN igmp-snooping nonflooding-enable
Disable multicast packets not to be
broadcasted within a VLAN undo igmp-snooping
nonflooding-enable
By default, unknown multicast packets are broadcasted within the VLAN.
24.3 Displaying and debugging IGMP Snooping
After the above configuration, execute display command in any view to display the
running of the IGMP Snooping configuration, and to verify the effect of the
configuration.
Table 24-6 Displaying and debugging IGMP Snooping
Operation Command
Display the information about current IGMP
Snooping configuration display igmp-snooping
configuration
Display IGMP Snooping statistics of
received and sent messages display igmp-snooping statistics
Display IP/MAC multicast group information
in the VLAN display igmp-snooping group
[ vlan vlanid ]
24.4 IGMP Snooping Configuration Example

24.4.1 Enable IGMP Snooping

I. Networking requirements