2-5
Enabling IGMP Snooping
Table 2-3
Enable IGMP Snooping
Operation
Command
Remarks
Enter system view
system
-
view
—
Enable IGMP Snooping
globally
igmp
-
snooping
enable
Required
By default, IGMP Snooping is
disabled globally.
Enter VLAN view
vlan vlan-id
—
Enable IGMP Snooping on the
VLAN
igmp
-
snooping enable
Required
By default, IGMP Snooping is
disabled on all the VLANs.
z
Before enabling IGMP Snooping in a VLAN, be sure to enable IGMP Snooping globally in system
view; otherwise the IGMP Snooping settings will not take effect.
z
If IGMP Snooping and VLAN VPN are enabled on a VLAN at the same time, IGMP queries are
likely to fail to pass the VLAN. You can solve this problem by configuring VLAN tags for queries.
For details, see
Configuring a VLAN Tag for Query Messages
.
Configuring the Version of IGMP Snooping
With the development of multicast technologies, IGMPv3 has found increasingly wide application. In
IGMPv3, a host can not only join a specific multicast group but also explicitly specify to receive or reject
the information from a specific multicast source. Working with PIM-SSM, IGMPv3 enables hosts to join
specific multicast sources and groups directly, greatly simplifying multicast routing protocols and
optimizing the network topology.
Table 2-4
Configure the version of IGMP Snooping
Operation
Command
Remarks
Enter system view
system-view
—
Enter VLAN view
vlan vlan-id
—
Configure the version of IGMP
Snooping
igmp-snooping version
version-number
Optional
The default IGMP Snooping
version is version 2.