The subordinate checks the health of the primary by sending heartbeats to the primary. Technically these health checks are requests to the primary for its current state.

The heartbeat is a request that is sent through a UDP socket. When the primary sees the heartbeat, it responds to the sender with its current state. The primary also sends heartbeats to the subordinate Passive Capture host machine to keep track of its state to determine whether it can failover to the subordinate.

Setting

Description

Heartbeat Interval

How long to wait between heartbeats

Heartbeat Timeout

The amount of time Passive Capture waits for a response to a heartbeat before you call it a timeout

Timeout Limit

The number of consecutive heartbeat timeouts that are allowed before a failover is forced