Command Line Interface
4-236
4
Command Usage
The robustness value is used in calculating the appropriate range for other
IGMP variables, such as
the Group Membership Interval (
ip igmp
last-memb-query-interval
, page 4-237)
, as well as the Other Querier Present
Interval, and the Startup Query Count (RFC 2236).
Example
ip igmp query-interval
This command configures the frequency at which host query messages are sent.
Use the no form to restore the default.
Syntax
ip igmp query-interval seconds
no ip igmp query-interval
seconds - The frequency at which the switch sends IGMP host-query
messages. (Range: 1-255)
Default Setting
125 seconds
Command Mode
Interface Configuration (VLAN)
Command Usage
• Multicast routers send host query messages to determine the interfaces that
are connected to downstream hosts requesting a specific multicast service.
Only the designated multicast router for a subnet sends host query messages,
which are addressed to the multicast address 224.0.0.1.
• For IGMP Version 1, the designated router is elected according to the
multicast routing protocol that runs on the LAN. But for IGMP Version 2, the
designated querier is the lowest IP-addressed multicast router on the subnet.
Example
The following shows how to configure the query interval to 100 seconds:
Console(config-if)#ip igmp robustval 3
Console(config-if)#
Console(config-if)#ip igmp query-interval 100
Console(config-if)#