3com 8807 사용자 가이드
446
C
HAPTER
42: IGMP C
ONFIGURATION
By default, the compatibility control function of the switch is disabled.
This command is often executed after IGMP or IGMP Spooning protocol is enabled
in the system.
in the system.
Configuring the IGMP
Version
Perform the following configuration in VLAN interface view.
By default, IGMP Version 2 is used.
c
CAUTION: The system does not support automatic switching between different
IGMP versions. Therefore, all routers on a subnet must be configured to run the
same IGMP version.
IGMP versions. Therefore, all routers on a subnet must be configured to run the
same IGMP version.
Configuring the Interval
to Send IGMP Query
Message
Multicast routers send IGMP query messages to discover which multicast groups
are present on attached networks. Multicast routers send query messages
periodically to refresh their knowledge of members present on their networks.
are present on attached networks. Multicast routers send query messages
periodically to refresh their knowledge of members present on their networks.
Perform the following configuration in VLAN interface view.
When there are multiple multicast routers on a network segment, the querier is
responsible for sending IGMP query messages to all hosts on the LAN.
responsible for sending IGMP query messages to all hosts on the LAN.
By default, the interval is 60 seconds.
Configuring the Interval
and the Number of
Querying IGMP Packets
On the shared network, it is the query router (querier) that maintains IGMP
membership on the interface. The igmp lastmember-queryinterval and igmp
robust-count commands are used to configure the interval and times of sending
IGMP group-specific query packets for the querier when it receives an IGMP leave
message from a host.
membership on the interface. The igmp lastmember-queryinterval and igmp
robust-count commands are used to configure the interval and times of sending
IGMP group-specific query packets for the querier when it receives an IGMP leave
message from a host.
■
The host sends the IGMP Leave message.
■
Upon receiving the message, IGMP querier sends the group-specific IGMP
query message for specified times (defined by the robust-value in igmp
robust-count, with the default value being 2) and at a time interval (defined
by the seconds in igmp lastmember-queryinterval, with the default value
being 1 second).
query message for specified times (defined by the robust-value in igmp
robust-count, with the default value being 2) and at a time interval (defined
by the seconds in igmp lastmember-queryinterval, with the default value
being 1 second).
Table 434 Enable compatibility control function of the switch
Operation
Command
Enabling compatibility control function of the switch
igmp-report enhance enable
Table 435 Configure the IGMP version
Operation
Command
Select the IGMP version that the router uses
igmp version { 2 | 1 }
Restore the default setting
undo igmp version
Table 436 Configure the interval to send IGMP query message
Operation
Command
Configure the interval to send IGMP query message igmp timer query seconds
Restore the default value
undo igmp timer query