code: public void markAsAlive(Node node) {
  		if (!NodeStatus.ALIVE.equals(node.getStatus())) {
  			socketToNodeMap.get(Utils.toKey(node)).markAsAlive();
  			sendEvent(node, NodeEventType.MARKED_AS_ALIVE);
  		}
  	}
docs: Marks the node as ALIVE in case of its status is not ALIVE.
  
  @param node
  - the node.