immediate-leave
Syntax
immediate-leave;
Hierarchy Level
[edit logical-systems logical-system-name protocols igmp interface interface-name], [edit protocols igmp interface interface-name], [edit bridge-domains bridge-domain-name protocols igmp-snooping], [edit bridge-domains bridge-domain-name protocols igmp-snooping interface interface-name], [edit bridge-domains bridge-domain-name protocols igmp-snooping vlan vlan-id interface interface-name], [edit routing-instances routing-instance-name bridge-domains bridge-domain-name protocols igmp-snooping], [edit routing-instances routing-instance-name bridge-domains bridge-domain-name protocols igmp-snooping interface interface-name], [edit routing-instances routing-instance-name bridge-domains bridge-domain-name protocols vlan vlan-id igmp-snooping interface interface-name], [edit protocols igmp-snooping vlan (all | vlan-name)], [edit protocols igmp-snooping vlan (all | vlan-name) interface interface-name], [edit logical-systems logical-system-name protocols mld interface interface-name], [edit protocols mld interface interface-name], [edit protocols mld-snooping vlan (all | vlan-name)], [edit protocols mld-snooping vlan vlan-name interface interface-name], [edit routing-instances instance-name protocols mld-snooping vlan vlan-name interface interface-name]
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 or MLD membership leave latency—it reduces the amount of time it takes for the switch to stop sending multicast traffic to an interface when the last host leaves the group.
EVPN-VXLAN multicast uses special IGMP group leave processing
to handle multihomed sources and receivers, so we don’t support
the immediate-leave option in EVPN-VXLAN networks.
IGMPv2, IGMPv3, MLDv1, and MLDv2 all have immediate leave disabled by default. In this state, the device does not track host memberships. 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.
With immediate leave 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 active simultaneously.
Immediate leave is supported for IGMPv2, IGMPv3, MLDv1 and MLDv2 on devices that support these protocols.
We recommend that you 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.
Release Information
Statement introduced in Junos OS Release 8.3.