3Com Switch 7750 Series
Command Reference Guide – Multicast Chapter 4 IGMP Configuration Commands
4-14
This command is only available on the IGMP query router running IGMP v2. For the
host running IGMP v1, this command cannot take effect because the host does not
send IGMP Leave packets when it leaves a group.
Related command: igmp lastmember-queryinterval and display igmp interface.
Example
# Set the robust value of the Vlan-interface 10 to 3.
<3Com> system-view
System View: return to User View with Ctrl+Z.
[3Com] interface Vlan-interface 10
[3Com-Vlan-interface10] igmp robust-count 3
4.1.14 igmp timer other-querier-present Syntax
igmp timer other-querier-present seconds
undo igmp timer other-querier-present
View
VLAN interface view
Parameter
seconds: Presence time of the IGMP querier, in the range of 1 to 131,070 in seconds.
Description
Use the igmp timer other-querier-present command to configure the presence time
of the IGMP querier.
Use the undo igmp timer other-querier-present command to restore the default
value.
By default, the presence time of the IGMP querier is twice the value of IGMP query
message interval, that is, 120 seconds.
On a shared network, i.e., there are multiple multicast routers on the same network
segment, the query router (querier for short) takes charge of sending query messages
periodically on the interface. If other non-queriers receive no query messages within
the valid period, the router will consider the previous querier to be invalid and the router
itself becomes a querier.
In IGMP version 1, the selection of a querier is determined by the multicast routing
protocol. In IGMP version 2, the router with the lowest IP address on the shared
network segment acts as the querier.
Related command: igmp timer query, and display igmp interface.