Help us improve your experience.

Let us know what you think.

Do you have time for a two-minute survey?

 

immediate-leave

 

Syntax

Hierarchy Level

Release Information

Statement introduced in Junos OS Release 8.5.

Statement introduced in Junos OS Release 11.1 for the QFX Series.

Statement introduced in Junos OS Release 18.1R1 for SRX1500 devices.

Description

Enable host tracking to allow the device to track the hosts that send membership reports, determine when the last host sends a leave message for the multicast group, and immediately stop forwarding traffic for the multicast group after the last host leaves the group. This setting helps to minimize IGMP membership leave latency.

If immediate leave is disabled (the default setting for both IGMPv2 and IGMPv3), when the device receives a leave report from a host, it sends out a group-specific query to all hosts. If no receiver responds with a membership report within a set interval, the device removes all hosts on the interface from the multicast group and stops forwarding multicast traffic to the interface.

When immediate leave is enabled, the device removes an interface from the forwarding-table entry immediately without first sending IGMP group-specific queries out of the interface and waiting for a response. The device prunes the interface from the multicast tree for the multicast group specified in the IGMP leave message. The immediate leave setting ensures optimal bandwidth management for hosts on a switched network, even when multiple multicast groups are being used simultaneously.

When enabled, immediate leave is supported for IGMPv2, IGMPv3, MLDv1 and MLDv2 for devices that support those protocols.

Note

We recommend to configure immediate leave with IGMPv2 and MLDv1 only when there is only one host on an interface. With IGMPv2 and MLDv1, only one host on a interface sends a membership report in response to a general query—any other interested hosts suppress their reports. Report suppression avoids a flood of reports for the same group, but it also interferes with host tracking because the device knows only about one interested host on the interface at any given time.

Default

Immediate leave is disabled.

Required Privilege Level

routing—To view this statement in the configuration.

routing-control—To add this statement to the configuration.