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hardware-assisted-keepalives (lfm)



Hierarchy Level

Release Information

Statement introduced in Junos OS Release 18.4R1.


On MX Series routers only, delegates the transmission and receipt of the LFM keepalive packets to the forwarding ASIC (that is, to the hardware) when you enable inline LFM. Inline transmission of LFM keepalive packets is also known as Inline-KA.

By default, LFM keepalive packets are transmitted by the periodic packet management (ppm) process of the line-card and not by the hardware. By enabling inline transmission of LFM keepalive packets, you can achieve maximum scaling of keepalive packets, reduction of the load on the ppm process, and support LFM in-service software upgrade (ISSU) for non-juniper peers (for a keepalive interval of 1 second).


Do not enable or disable inline transmission of LFM when an LFM session is already established. To enable or disable inline transmission, you must first deactivate the existing established LFM session using the deactivate command, and then reactivate the LFM session using the activate command after enabling or disabling inline LFM.


Inline transmission is disabled by default.

Required Privilege Level

interface—To view this statement in the configuration.

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