/** Shut down this instance of the datanode. Returns only after shutdown is complete. */ public void shutdown() { shouldRun = false; try { if (infoServer != null) infoServer.stop(); } catch (Exception e) { LOG.warn("Exception shutting down SecondaryNameNode", e); } try { if (checkpointImage != null) checkpointImage.close(); } catch (IOException e) { LOG.warn(StringUtils.stringifyException(e)); } }