H3C S7500 Series Ethernet Switches Operation Manual

Operation Manual – Multicast
H3C S7500 Series Ethernet Switches Chapter 6
IGMP Configuration
6-6
To do... Use the command... Remarks
Enter system view system-view —
Enable the multicast
routing protocol
multicast
routing-enable
Enable the multicast
routing protocol.
Enter VLAN interface view
interface Vlan-interface
interface-number
—
Enable IGMP on the
current interface
igmp enable
Required
By default, if IP multicast
routing is enabled
globally, IGMP is enabled
on all the layer-3
interfaces automatically.
Configure the IGMP
version for the Layer 3
switch (router)
igmp version { 1 | 2 }
Optional
IGMPv2 is used by
default.
Caution:
An IGMP version cannot be switched to other versions automatically. So all the Layer 3
switches on a subnet must be configured to use the same IGMP version.
6.2.2 Configuring IGMP Query Messages
I. IGMP general query messages
The Layer 3 switch sends IGMP general query messages to the connected network
segment periodically to get to know which multicast groups in the network segment
have members according to the returned IGMP report messages. The multicast router
also sends query messages periodically. When it receives the IGMP report message of
a group member, it will refresh the membership information of the network segment.
II. IGMP group-specific messages
The query router (querier for short) maintains the IGMP report messages on interfaces
of the shared network. After the related features are configured, the IGMP querier will
send IGMP group-specific query messages at the user-defined interval for the
user-defined times when it receives the IGMP leave messages from the host.
Suppose a host in a multicast group decides to leave the multicast group. The detailed
procedures are as follows:
z The host sends an IGMP leave message.