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.

Format

igmp timer other-querier-present interval

undo igmp timer other-querier-present

Parameters

Parameter	Description	Value
interval	Specifies the other querier present timer.	The value is an integer that ranges from 60 to 300, in seconds.

Views

GE interface view, XGE interface view, MultiGE interface view, 25GE interface view, 40GE interface view, 100GE interface view, Eth-Trunk interface view, GE sub-interface view, XGE sub-interface view, MultiGE sub-interface view, 25GE sub-interface view, 40GE sub-interface view, 100GE sub-interface view, Eth-Trunk sub-interface view, VLANIF interface view, loopback interface view

Default Level

2: Configuration level

Usage Guidelines

Usage Scenario

When a user network segment connects to multiple Layer 3 multicast devices, only one Layer 3 multicast device is elected as the IGMP querier to send Query messages to hosts on the network segment. If the querier fails to send Query messages, group memberships cannot be created or maintained. Non-queriers running IGMPv2 or IGMPv3 start the other querier present timer after they fail in the querier election. If the non-queriers do not receive Query messages from the querier before the timer times out, they consider the querier failed and start a new querier election.

Prerequisites

IP 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.
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.

If the other querier present timer value is shorter than the interval for sending IGMP General Query messages, the querier election is triggered frequently.

Example

# On VLANIF100, set the other querier present timer to 200 seconds.

<HUAWEI> system-view
[HUAWEI] multicast routing-enable
[HUAWEI] interface vlanif 100
[HUAWEI-Vlanif100] igmp timer other-querier-present 200

# On GE0/0/1, set the other querier present timer to 200 seconds.

<HUAWEI> system-view
[HUAWEI] multicast routing-enable
[HUAWEI] interface gigabitethernet 0/0/1
[HUAWEI-GigabitEthernet0/0/1] undo portswitch
[HUAWEI-GigabitEthernet0/0/1] igmp timer other-querier-present 200