The send-router-alert command enables the router to send IGMP messages containing the Router-Alert option in IP headers.
The undo send-router-alert command disables the router from sending IGMP messages containing the Router-Alert option in IP headers.
By default, IP headers of IGMP messages sent by the router contain the Router-Alert option.
Usage Scenario
By default, IP headers of IGMP messages sent by the router contain the Router-Alert option. If the router communicates with a device that does not support the Router-Alert option, run the undo send-router-alert command to disable the router from sending IGMP messages containing the Router-Alert option in IP headers.
Prerequisites
The multicast routing function has been enabled using the multicast routing-enable command in the public network instance view or VPN instance view.
Configuration Impact
After the undo send-router-alert command is run, the router can communicate with a device that does not support the Router-Alert option.
Precautions
The function of this command is the same as the function of the igmp send-router-alert command used in the interface view. The configuration in the IGMP view is effective for all interfaces, whereas the configuration in the interface view is effective only for the specified interface. The configuration in the interface view takes precedence over the configuration in the IGMP view. The configuration in the IGMP view is used only when the configuration in the interface view is not available.