M
ULTICAST
F
ILTERING
C
OMMANDS
-109
Command Mode
Interface Configuration (VLAN)
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 3-111)
, as well as the Other
Querier Present Interval, and the Startup Query Count (RFC 2236).
Example

ip igmp query-interval

Use this command to configure 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 determ ine 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
Console(config-if)#ip igmp robustval 3
Console(config-if)#