code: public void acknowledgeHeartBeat( Instance scopedInstance ) {
  
  		String count = scopedInstance.data.get( MISSED_HEARTBEATS );
  		if( count != null
  				&& Integer.parseInt( count ) > THRESHOLD )
  			this.logger.info( "Agent " + InstanceHelpers.computeInstancePath( scopedInstance ) + " is alive and reachable again." );
  
  		// Store the moment the first ACK (without interruption) was received.
  		// If we were deploying, store it.
  		// If we were in problem, store it.
  		// If we were already deployed and started, do NOT override it.
  		if( scopedInstance.getStatus() != InstanceStatus.DEPLOYED_STARTED
  				|| ! scopedInstance.data.containsKey( Instance.RUNNING_FROM ))
  			scopedInstance.data.put( Instance.RUNNING_FROM, String.valueOf( new Date().getTime()));
  
  		scopedInstance.setStatus( InstanceStatus.DEPLOYED_STARTED );
  		scopedInstance.data.remove( MISSED_HEARTBEATS );
  	}
docs: Acknowledges a heart beat.
  @param scopedInstance a root instance