Cisco Systems 3750E Changing the Maximum Query Response Time for IGMPv2, Configuring the Switch as a Statically Connected Member

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Catalyst 3750-E and 3560-E Switch Software Configuration Guide
OL-9775-02
Chapter42 Configuring IP Multicast Routi ng
Configuring Optional IGMP Features
To return to the default setting, use the no ip igmp querier-timeout interface configuration command.
Changing the Maximum Query Response Time for IGMPv2
If you are using IGMPv2, you can change the maximum query response time advertised in IGMP
queries. The maximum query response time enables the switch to quickly detect that there are no more
directly connected group members on a LAN. Decreasing the value enab les the switch to prune groups
faster.
Beginning in privileged EXEC mode, follow these steps to change the maximu m query response time.
This procedure is optional.
To return to the default setting, use the no ip igmp query-max-response-time interface configuration
command.
Configuring the Switch as a Statically Connected Member
Sometimes there is either no group member on a network segment or a host cannot report its group
membership by using IGMP. However, you might want multicast traffic to go to that network segment.
These are ways to pull multicast traffic down to a network segment:
•Use the ip igmp join-group interface configuration command. With this method, the switch accepts
the multicast packets in addition to forwarding them. Accepting the multicast packets prevents the
switch from fast switching.
•Use the ip igmp static-group interface configuration command. With this method, the switch does
not accept the packets itself, but only forwards them. This method enables fast switching. The
outgoing interface appears in the IGMP cache, but the switch itself is not a member, as evidenced
by lack of an L (local) flag in the multicast route entry.
Step5 show ip igmp interface [interface-id] Verify your entries.
Step6 copy running-config startup-config (Optional) Save your entries in the configuration file.
Command Purpose
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 interface interface-id Specify the interface to be configured, and enter interface configuration
mode.
Step3 ip igmp query-max-response-time
seconds
Change the maximum query response time advertised in IGMP queries.
The default is 10 seconds. The range is 1 to 25.
Step4 end Return to privileged EXEC mode.
Step5 show ip igmp interface [interface-id] Verify your entries.
Step6 copy running-config startup-config (Optional) Save your entries in the configuration file.