Understanding Chassis Cluster Control Link Heartbeats

Junos OS transmits heartbeat signals over the control link at a configured interval. The system uses heartbeat transmissions to determine the “health” of the control link. If the number of missed heartbeats has reached the configured threshold, the system assesses whether a failure condition exists.

You specify the heartbeat threshold and heartbeat interval when you configure the chassis cluster.

The system monitors the control link's status by default.

For dual control links, which are supported on the SRX5000 and SRX3000 lines, the Juniper Services Redundancy Protocol process (jsrpd) sends and receives the control heartbeat messages on both control links. As long as heartbeats are received on one of the control links, Junos OS considers the other node to be alive.

Related Topics

• Junos OS Feature Support Reference for SRX Series and J Series Devices
• Understanding Chassis Cluster Control Links
• Understanding Chassis Cluster Dual Control Links
• Connecting Dual Control Links for SRX Series Devices in a Chassis Cluster
• Understanding Chassis Cluster Control Link Failure and Recovery
• Understanding the Chassis Cluster Control Plane