igmp lastmember-queryinterval

Function

The igmp lastmember-queryinterval command sets the interval at which an IGMP querier sends IGMP last-member query messages after it receives an IGMP Leave message from a host.

The undo igmp lastmember-queryinterval command restores the default setting.

By default, an IGMP querier sends IGMP last-member query messages at an interval of 1s.

Format

igmp lastmember-queryinterval interval

undo igmp lastmember-queryinterval

Parameters

Parameter Description Value
interval

Specifies an interval at which an IGMP querier sends IGMP last-member query messages.

The value is an integer ranging from 1 to 25, in seconds.

Views

100ge sub-interface view, 100GE interface view, 10GE sub-interface view, 10GE interface view, 200GE sub-interface view, 25GE sub-interface view, 25GE interface view, 400GE sub-interface view, 400GE interface view, 40GE sub-interface view, 40GE interface view, 50GE sub-interface view, 50GE interface view, Eth-Trunk sub-interface view, Eth-Trunk interface view, FlexE interface view, GE optical interface view, GE sub-interface view, GE interface view, GE electrical interface view, Global VE sub-interface view, Loopback interface view, PW-VE sub-interface view, Tunnel interface view, VBDIF interface view, VE sub-interface view, VLANIF interface view, Virtual template view

Default Level

2: Configuration level

Task Name and Operations

Task Name Operations
igmp write

Usage Guidelines

Usage Scenario

If multiple multicast devices are connected to a shared network segment where user hosts reside, these multicast devices automatically elect a unique querier. The querier maintains IGMP group memberships by sending IGMP query messages. To set the interval at which IGMP last-member query messages are sent, run the igmp lastmember-queryinterval command.

The igmp lastmember-queryinterval command is valid only when the querier runs IGMPv2 or IGMPv3. A last-member query is also known as a group-specific query. IGMPv3 also supports source/group-specific queries.

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 receiving a Leave message for a group, the querier sends group-specific query messages constantly to check whether there is a member of the group. The interval at which the querier sends group-specific query messages is specified by interval, and the number of times for sending group-specific query messages is specified by robust-value in the igmp robust-count command or the robust-count command.

If there is a member of a group on the network segment, the member must send a Report message within the maximum response time. The maximum response time can be set by using the igmp max-response-time command or the max-response-time command.

If the querier receives a Report message within the period obtained by the value of robust-value multiplied by the value of interval, it continues to maintain the memberships for the group. Otherwise, the querier considers that there is no member of the group on the network segment, and therefore does not maintain the memberships for the group.

Precautions

The function of the igmp lastmember-queryinterval command is the same as the function of the lastmember-queryinterval command in the IGMP 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.

Example

# Specify 3s as the interval at which GE 0/1/0 sends last-member query messages (group-specific query messages).
<HUAWEI> system-view
[~HUAWEI] multicast routing-enable
[*HUAWEI] interface GigabitEthernet 0/1/0
[*HUAWEI-GigabitEthernet0/1/0] undo portswitch
[*HUAWEI-GigabitEthernet0/1/0] igmp lastmember-queryinterval 3
Copyright © Huawei Technologies Co., Ltd.
Copyright © Huawei Technologies Co., Ltd.
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