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Syntax (for monitor)

Syntax (for monitor-object)

Hierarchy Level


Configure Bidirectional Forwarding Detection (BFD) monitoring to detect failures in a network. You can configure Multinode High Availability to monitor one or more links using BFD. This configuration triggers a failover in the event of BFD failure. Configure BFD liveliness by specifying source and destination IP and the interface where the peer device is directly connected to.



Destination IPV4/IPV6 address for BFD monitoring

interface interface

Name of the interface for single-hop sessions

routing-instance routing-instance

Routing instance to locate the route


BFD Monitoring session type. Configure BFD session mode to be single-hop or multihop. By default, BGP uses single-hop BFD sessions if the peer is directly connected to the router’s interface.

src-ip src-ip

Source IPV4/IPV6 address for BFD monitoring

weight number ( monitor-object) —

BFD monitoring weight value for SRG monitoring object.

  • Range: 1 through 1000

threshold (monitor-object) —BFD-liveliness monitoring threshold value.
  • Range: 1 through 1000

Within a monitor-object, whenever the particular object fails to trigger a failover as result of BFD monitoring, the system considers the event as monitoring failure and adds a count to BFD-liveliness.

When the count exceeds the threshold value BFD-liveliness, the system adds the count to parent monitoring-object's threshold value. Monitoring-object's threshold also includes threshold values of interface monitoring and IP monitoring.

When the sum of the weights of all monitor objects bound to the SRG reaches a value equal to or greater than the threshold value configured on the SRG, the system triggers a monitor failure for that SRG. SRG fails over to the other node.

Required Privilege Level

interface—To view this statement in the configuration.

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

Release Information

Statement introduced in Junos OS Release 20.4R1.