WitnessHeartbeatResponse response = rpcClient.heartbeat(request);
            
            if (response.isSuccess()) {
                registration.updateHeartbeat();
            } else {
                log.warn("Witness heartbeat failed for: {}", registration.getRegistrationId());
            }
            
        } catch (Exception e) {
            log.debug("Heartbeat error for registration: {}", 

        registration.updateHeartbeat();

        // After update, should not be expired with long timeout
        assertFalse(registration.isExpired(60000));

        // Verify heartbeat was actually updated
        assertTrue(registration.getLastHeartbeat() > initialTime);
    }

    @Test
    void testExpiration() throws InterruptedException {

		return nil
	}
	clnt.SetCustomTransport(globalRemoteTargetTransport)
	return clnt
}

// heartBeat performs liveness check on remote endpoints.
func (sys *BucketTargetSys) heartBeat(ctx context.Context) {
	hcTimer := time.NewTimer(defaultHealthCheckDuration)
	defer hcTimer.Stop()
	for {
		select {
		case <-hcTimer.C:
			sys.hMutex.RLock()

    /** WitnessUnregister operation number */
    public static final int WITNESS_UNREGISTER = 1;
    /** WitnessAsyncNotify operation number */
    public static final int WITNESS_ASYNC_NOTIFY = 2;
    /** Witness heartbeat operation number */
    public static final int WITNESS_HEARTBEAT = 3;

    // Common return codes from MS-SWN specification
    /** Operation completed successfully */
    public static final int ERROR_SUCCESS = 0x00000000;

    /**
     * @return timeout for persistent handles in milliseconds
     */
    long getPersistentHandleTimeout();

    /**
     * Gets the witness heartbeat timeout in milliseconds.
     *
     * @return the heartbeat timeout
     */
    long getWitnessHeartbeatTimeout();

    /**
     * Gets the witness registration timeout in milliseconds.
     *
     * @return the registration timeout

#                                                Coordinator
#                                                     ------

# Interval (seconds) for polling heartbeats and events.
coordinator.poll.interval=60
# Time-to-live (ms) for instance heartbeat documents.
coordinator.heartbeat.ttl=180000
# Time-to-live (ms) for operation lock documents.
coordinator.operation.ttl=7200000
# Maximum number of retries for acquiring an operation lock.

    /**
     * Flag indicating whether SMB Witness protocol should be used for failover
     */
    protected boolean useWitness = false; // Disabled by default
    /**
     * Timeout in milliseconds for witness heartbeat messages
     */
    protected long witnessHeartbeatTimeout = 120000; // 2 minutes
    /**
     * Timeout in milliseconds for witness registration
     */

focused on stability and performance improvements in the 1.13 release.  A new alpha feature is introduced to improve the mechanism that nodes heartbeat back to the control plane.  The `NodeLease` feature results in the node using a `Lease` resource in the `kube-node-lease` namespace that is renewed periodically.  The `NodeStatus` that was used previously to heartbeat back to the control plane is only updated when it changes.  This reduces load on the control plane for large clusters. The Kubelet plugin...

     * @return The value of found property. (NotNull: if not found, exception but basically no way)
     */
    String getCoordinatorHeartbeatTtl();

    /**
     * Get the value for the key 'coordinator.heartbeat.ttl' as {@link Integer}. <br>
     * The value is, e.g. 180000 <br>
     * comment: Time-to-live (ms) for instance heartbeat documents.

- kubelet: fix fail to close kubelet->API connections on heartbeat failure when bootstrapping or client certificate rotation is disabled ([#78016](https://github.com/kubernetes/kubernetes/pull/78016), [@gaorong](https://github.com/gaorong))