H3C S7500E Series Ethernet Switches Operation Manual

Operation Manual – Multicast
H3C S7500E Series Ethernet Switches Chapter 2 IGMP Snooping Configuration
2-12
2.4.4 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 an IGMP query is heard, the simulated host gives a response. Thus, the switch
can continue receiving multicast data.
A simulated host acts like a real host, as follows:
z When a port is configured as a simulated member host, the switch sends an
unsolicited IGMP report through that port.
z After a port is configured as a simulated member host, the switch responds to
IGMP general queries by sending IGMP reports through that port.
z When the simulated joining function is disabled on a port, the switch sends an
IGMP leave group message through that port.
Follow these steps to configure simulated joining:
To do... Use the command... Remarks
Enter system view
system-view
—
Enter Ethernet
port view
interface interface-type
interface-number
Enter the
corresponding
view
Enter port
group view
port-group { manual
port-group-name |
aggregation agg-id }
Required
Use either
command.
Configure simulated (*, G) or (S,
G) joining
igmp-snooping host-join
group-address [ source-ip
source-address ] vlan vlan-id
Required
Disabled by
default
 Note:
z Each simulated host is equivalent to an independent host. For example, when
receiving an IGMP query, the simulated host corresponding to each configuration
responds respectively.
z Unlike a static member port, a port configured as a simulated member host will age
out like a dynamic member port.