Configuring Simulated Joining - 3Com S7906E Configuration Manual

A static (S, G) joining can take effect only if a valid multicast source address is specified and IGMP
snooping version 3 is currently running.
A static member port does not respond to queries from the IGMP querier; when static (*, G) or (S, G)
joining is enabled or disabled on a port, the port does not send an unsolicited IGMP report or an
IGMP leave message.
If IGMP is enabled on the virtual interface of a VLAN on a switch and you want a port in that VLAN
to be a static multicast group or source-group member port, in addition to configuring the port as a
static member port, you need to use the igmp static-group command to configure the VLAN
interface to be a static member of the multicast group or source and group. For details of the igmp
static-group command, refer to IGMP Commands in the IP Multicast Volume.
Static member ports and static router ports never age out. To remove such a port, you need to use
the corresponding undo command.

Configuring Simulated Joining

Generally, a host running IGMP responds to IGMP queries from the IGMP querier. If a host fails to
respond due to some reasons, the multicast router may deem that no member of this multicast group
exists on the network segment, and therefore will remove the corresponding forwarding path.
To avoid this situation from happening, you can enable simulated joining on a port of the switch, namely
configure the port as a simulated member host for a multicast group. When receiving an IGMP query,
the simulated host gives a response. Thus, the switch can continue receiving multicast data.
A simulated host acts like a real host, as follows:
When a port is configured as a simulated member host, the switch sends an unsolicited IGMP
report through that port.
After a port is configured as a simulated member host, the switch responds to IGMP general
queries by sending IGMP reports through that port.
When the simulated joining function is disabled on a port, the switch sends an IGMP leave
message through that port.
Follow these steps to configure simulated joining:
To do...
Enter system view
Enter Ethernet port/ONU
port/Layer 2 aggregate
interface view or port group
view
Configure simulated (*, G) or
(S, G) joining
Use the command...
system-view
interface interface-type
interface-number
port-group manual port-group-name
igmp-snooping host-join
group-address [ source-ip
source-address ] vlan vlan-id
1-13
Remarks
—
Required
Use either approach
Required
Disabled by default