3Com Switch 7750 Configuration Guide

456 CHAPTER 46: IGMP CONFIGURATION
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CAUTION: When there are multiple multicast routers in a network segment, the
querier is responsible for sending IGMP query messages to all the hosts in the
network segment.
Configuring IGMP
Multicast Groups on the
Interface
You can perform the following configurations on the interface for the IGMP
multicast groups:
■ Limit the number of multicast groups
■ Limit the range of multicast groups that the interface serves
Limiting the number of joined multicast groups
If the number of joined IGMP groups on the multicast routing interface of the
switch is not limited, the memory of the switch may be used out and the routing
Enable the multicast routing
protocol
multicast routing-enable Required
Enter VLAN interface view interface Vlan-interface
interface-number
-
Enable IGMP on the current
interface
igmp enable Required
By default, if the IP multicast
routing protocol is enabled
globally, IGMP is enabled on
all the layer-3 interfaces
automatically.
Configure the query interval igmp timer query seconds Optional
The query interval is 60
seconds by default.
Configuring the interval of
sending IGMP group-specific
query messages
igmp
lastmember-queryinterval
seconds
Optional
By default, the interval of
sending IGMP group-specific
query messages is 1 second.
Configuring the times of
sending IGMP group-specific
query messages
igmp robust-count
robust-value
Optional
By default, the times of
sending IGMP group-specific
query messages is 2.
Configure the maximum
lifetime of an IGMP querier
igmp timer
other-querier-present
seconds
Optional
■ The lifetime of an IGMP
querier is 120 seconds by
default.
■ If the Layer 3 switch does
not receive query
messages in two times of
the interval specified by
the igmp timer query
command, the former
querier is considered as
ineffective.
Configure the maximum
IGMP query response time
igmp max-response-time
seconds
Optional
The maximum IGMP query
response time is 10 seconds.
Table 364 Configure IGMP query messages
Operation Command Description