3com S7906E 설치 설명서

 

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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.  

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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.  

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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.  

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Static member ports and static router ports never age out. To remove such a port, you need to use 

the corresponding undo command. 

 

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: 

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When a port is configured as a simulated member host, the switch sends an unsolicited IGMP 

report through that port. 

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After a port is configured as a simulated member host, the switch responds to IGMP general 

queries by sending IGMP reports through that port.  

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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:  

Enter system view 

system-view 

— 

interface interface-type 
interface-number 

Enter Ethernet port/ONU 
port/Layer 2 aggregate 
interface view or port group 
view 

port-group manual port-group-name 

Required 

Use either approach 

Configure simulated (*, G) or 
(S, G) joining  

igmp-snooping host-join 
group-address [ source-ip 
source-address ] vlan vlan-id 

Required 

Disabled by default