hdlc keepalive

Syntax

hdlc keepalive [ seconds ]

no hdlc keepalive

Release Information

Command introduced before JunosE Release 7.1.0.

Description

Specifies a keepalive value. The keepalive mechanism tracks the health of the connection. The no version turns off the keepalive feature.

When the keepalive timer expires, the interface increments its own counter; then it compares the value of this counter with the last value received from a peer. If the difference between the values of the two counters is greater than three, the Cisco HDLC interface is declared down. After that, the interface sends a keepalive message containing the value of its counter and the last received value of the peer’s counter.

The router stores the values received in keepalive messages from a peer interface. If the interface is down, the router compares the received value of its own counter with the value from the peer. If the difference between the values of the two counters is less than four, the router declares the interface to be up. Both sides have to configure the same value for the keepalive interval. If the keepalive interval is 10 seconds, then a failed link is detected between 30 and 40 seconds after failure.

Options

Mode

Interface Configuration, Subinterface Configuration