igmp timer other-querier-present
Function
The igmp timer other-querier-present command sets the other querier present timer on an interface.
The undo igmp timer other-querier-present command restores the default value of the other querier present timer on an interface.
The formula used to calculate the other querier present timer value is:
Other querier present timer = Robustness variable x Interval for sending IGMP General Query messages + 1/2 x Maximum response time for IGMP query messages
If the default values of the robustness variable, the interval for sending IGMP General Query messages, and the maximum response time for IGMP query messages are used, the other querier present timer value is 125s.
Parameters
| Parameter | Description | Value |
|---|---|---|
| interval | Specifies the other querier present timer. | The value is an integer that ranges from 60 to 300, in seconds. |
Usage Guidelines
Usage Scenario
When a user network segment connects to multiple Layer 3 multicast devices, one multicast device is elected as the querier to periodically send General Query messages to the network segment. If the non-queriers do not receive any General Query message from the querier when their querier present timer expires, they consider the querier invalid, and trigger election of a new querier.
In IGMPv1, the querier is determined by PIM. In IGMPv2 and IGMPv3, the Layer 3 multicast device with the smallest IP address functions as the querier.
Prerequisites
Multicast routing has been enabled using the multicast routing-enable command.
Precautions
The igmp timer other-querier-present command applies only to IGMPv2 and IGMPv3.
If the other querier present timer value is shorter than the interval for sending IGMP General Query messages, the querier election is triggered frequently.
The igmp timer other-querier-present command has the same function as the timer other-querier-present command used in the IGMP view. The configuration in the IGMP view takes effect for all interfaces, whereas the configuration in the interface view takes effect 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 no configuration is performed in the interface view.
