2-13 
z  When an Ethernet port is configured as a simulated member host, the switch sends an IGMP report 
through this port. Meanwhile, the switch sends the same IGMP report to itself and establishes a 
corresponding IGMP entry based on this report. 
z  When receiving an IGMP general query, the simulated host responds with an IGMP report. 
Meanwhile, the switch sends the same IGMP report to itself to ensure that the IGMP entry does not 
age out.  
z  When the simulated joining function is disabled on an Ethernet port, the simulated host sends an 
IGMP leave message. 
Therefore, to ensure that IGMP entries will not age out, the port must receive IGMP general queries 
periodically. 
Table 2-16 Configure a port as a simulated group member  
Operation  Command  Remarks 
Enter system view  system-view 
—
 
Enter Ethernet port view 
interface interface-type 
interface-number 
—
 
Configure the current port as a 
simulated multicast group 
member 
igmp host-join group-address 
[source-ip source-address ] vlan 
vlan-id 
Required  
Simulated joining is 
disabled by default. 
 
 
z  Before configuring a simulated host, enable IGMP Snooping in VLAN view first.  
z  The port to be configured must belong to the specified VLAN; otherwise the configuration does not 
take effect. 
z  You can use the source-ip source-address command to specify a multicast source address that 
the port will join as a simulated host. This configuration takes effect when IGMPv3 Snooping is 
enabled in the VLAN.  
 
Configuring a VLAN Tag for Query Messages 
By configuring the VLAN in which IGMP general and group-specific queries forwarded and sent by 
IGMP Snooping switches are transmitted, you can enable multicast packet forwarding between different 
VLANs In a Layer-2 multicast network environment. 
Table 2-17 Configure VLAN Tag for query message 
Operation  Command  Remarks 
Enter system view 
system-view 
—
 
Enable IGMP Snooping 
igmp-snooping enable 
Required 
By default, IGMP Snooping is 
disabled. 
Configure a VLAN tag for query 
messages 
igmp-snooping 
vlan-mapping vlan vlan-id 
Required