Configuring an IGMPv1 Querier

Configuring an IGMPv1 querier involves setting the interval for sending General Query messages and a robustness variable.

Prerequisites

Before configuring an IGMPv1 querier, complete the following task:

Configuring a unicast routing protocol to interconnect the entire multicast domain.
Configuring Basic IGMP Functions

Context

The querier periodically sends IGMP query messages on a shared network connected to receivers. When receiving a Report message from a member, the querier refreshes information about the members. If non-queriers do not receive a general query message within the Keepalive period of other IGMP queriers, the querier is considered faulty, and a new round of querier election is triggered automatically.

The configuration involves the following cases:

Global configuration: It is valid on all interfaces.
Configuration on an interface: The configuration on an interface takes precedence over the global configuration. If the interface is not configured, the global configuration is used.

The aging time of dynamic member interfaces must be same on Layer 3 devices and attached Layer 2 devices. Otherwise, multicast data cannot be correctly transmitted between the Layer 2 and 3 networks.

Procedure

Global Configuration
1. Access the system view.
  system-view
2. Access the IGMP view.
  igmp [ vpn-instance vpn-instance-name ]
3. Set the interval for sending general query messages.
  timer query interval
  
  By default, the interval for sending general query messages is 60 seconds.
4. Set the robustness variable.
  robust-count robust-value
  
  By default, the IGMP robustness variable is 2.
Configuration on an Interface
1. Access the system view.
  system-view
2. Access the interface view.
  interface interface-type interface-number
3. Set the interval for sending general query messages.
  igmp timer query interval
  
  By default, the interval for sending general query messages is 60 seconds.
4. Set the robustness variable.
  igmp robust-count robust-value
  
  By default, the IGMP robustness variable is 2.