3com S7906E 설치 설명서

 

1-18 

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Configure any unicast routing protocol so that all devices in the domain are interoperable at the 

network layer. 

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Enable IP multicast routing.  

You can enable IGMP proxying on the interface in the direction toward the root of the multicast 

forwarding tree to make the device serve as an IGMP proxy.  

Follow these steps to enable IGMP proxying: 

Enter system view 

— 

Enter interface view 

interface interface-type 
interface-number 

— 

Enable the IGMP proxying 
feature 

igmp proxying enable 

Required 

Disabled by default. 

 

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Each device can have only one interface serving as the proxy interface. In scenarios with multiple 

instances, IGMP proxying is configured on only one interface per instance.  

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You cannot enable IGMP on interfaces with IGMP proxying enabled. Moreover, only the igmp 

require-router-alert, igmp send-router-alert, and igmp version commands can take effect on 

such interfaces.  

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You cannot enable other multicast routing protocols (such as PIM-DM or PIM-SM) on interfaces 

with IGMP proxying enabled, or vice versa. However, the source-lifetime,  source-policy, and 

ssm-policy commands configured in PIM view can still take effect. In addition, in IGMPv1, the 

designated router (DR) is elected by the working multicast routing protocol (such as PIM) to serve 

as the IGMP querier. Therefore, a downstream interface running IGMPv1 cannot be elected as the 

DR and thus cannot serve as the IGMP querier.  

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You cannot enable IGMP proxying on a VLAN interface with IGMP snooping enabled, or vice 

versa.  

 

Typically, only queriers are able to forward multicast traffic while non-queriers have no multicast 

forwarding capabilities, to avoid duplicate multicast flows. It is the same on IGMP proxy devices. Only 

the downstream interfaces acting as a querier can forward multicast traffic to downstream hosts.  

However, when a downstream interface of a proxy device fails to win the querier election, you need to 

enable multicast forwarding on this interface.  

Follow these steps to enable multicast forwarding on a downstream interface 

Enter system view 

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