link:http://hongliangpan.iteye.com/blog/243149
安全监控 , 网络技术 08月 22nd. 2008, 12:39am
在网络环境下,Ping是一个很重要的命令,通常用来检测远程的机器是否能够连通以及连接的质量如何。如果定时Ping一些机器,然后将响应时间在时间轴上画成图像,那就能非常直观的显示出网络信息,达到减脂网络的目的。
JRobin是一个很好的存储和用图形展示基于时间序列数据的工具。可以使用Java编写代码将操作系统中的Ping命令与JRobin结合起来,通过Ping命令获取数据信息,用JRobin保存和以图形方式显示Ping的响应时间,从而开发出一个简单的网络监视工具。
1、Ping
Ping命令的用法很简单,一般在其后接目标机器的域名或IP地址。不过Windows和Linux下的用法有所不同:
(1)在Windows下,执行 ping www.baidu.com 命令后,连续Ping四次,然后返回结果;在Linux下,执行同样的命令好,一直Ping下去,直到使用Ctrl+C终止该命令。
(2)在Windows下,通过 -n 来指定Ping的次数;在Linux下,使用 -c 选项。
2、JRobin
JRobin的介绍可以参考:
(1)JRobin网站:http://www.jrobin.org/
(2)JRobin简介:http://hi.baidu.com/li_zhongnan/blog/item/6fef0499a408940d6e068cbf.html
3、在Java中的实现机制:
(1)获取Ping响应时间:通过ProcessBuilder创建一个代表外部Ping命令的Process,启动Process执行Ping命令,获取Ping命令的标准输出,对标准输出进行解析,取出响应时间数据。如果需要能在Windows和Linux平台上执行,可以通过环境变量判断平台然后选择针对不同的平台、带不同的参数、执行不同的命令、用不同的方法解析命令输出,最终输出相同的结果。
在Java中执行外部命令可以参考:http://hi.baidu.com/li_zhongnan/blog/item/318effa9611d2bf91f17a26a.html
(2)保存历史数据:使用JRobin的机制来保存Ping的历史数据。
(3)定时执行:将执行Ping命令获取响应时间、保存相应时间数据到JRobin封装在一个函数,在TimerTask中调用该函数,通过Timer调度来定时执行。
(4)生成图形:使用JRobin来生成Ping响应时间图形。
(5)扩展性考虑:
a. 通过参数设置多个需要监视的对象,可以对多个域名或IP地址进行监视并将数据画在衣服图上;
b. 可以指定数据和图形的保存目录;
c. 提供启动和停止监视的功能;
d. 可以随时调用生成图形的操作,从而可以实现实时监控的功能。
4、看看成果:
5、事例代码:
import java.awt.Color; import java.awt.Font; import java.io.BufferedReader; import java.io.File; import java.io.IOException; import java.io.InputStreamReader; import java.io.PrintWriter; import java.util.ArrayList; import java.util.Date; import java.util.List; import java.util.Timer; import java.util.TimerTask; import java.util.logging.Logger; import org.jrobin.core.RrdDb; import org.jrobin.core.RrdDef; import org.jrobin.core.Sample; import org.jrobin.graph.RrdGraph; import org.jrobin.graph.RrdGraphDef; public class PingMonitor { public static String[] execute(String command) { String[] strs = null; File scriptFile = null; try { List<String> cmdList = new ArrayList<String>(); String osName = System.getProperty(”os.name”); if (osName.indexOf(”Windows”) > -1) { cmdList.add(”CMD.EXE”); cmdList.add(”/C”); cmdList.add(command); } else { scriptFile = File.createTempFile(”monitor”, “.sh”); cmdList.add(”/bin/bash”); String fileName = scriptFile.getCanonicalPath(); PrintWriter writer = new PrintWriter(scriptFile); writer.println(command); writer.flush(); writer.close(); cmdList.add(fileName); } ProcessBuilder pb = new ProcessBuilder(cmdList); Process p = pb.start(); p.waitFor(); String line = null; BufferedReader stdout = new BufferedReader(new InputStreamReader(p .getInputStream())); List<String> stdoutList = new ArrayList<String>(); while ((line = stdout.readLine()) != null) { stdoutList.add(line); } BufferedReader stderr = new BufferedReader(new InputStreamReader(p .getErrorStream())); List<String> stderrList = new ArrayList<String>(); while ((line = stderr.readLine()) != null) { stderrList.add(line); } strs = stdoutList.toArray(new String[0]); } catch (Exception e) { e.printStackTrace(); } finally { if (scriptFile != null) scriptFile.delete(); } return strs; } private String dataFormat = “%5.1f ms”; private Logger logger = Logger.getLogger(this.getClass().getName()); private String monitorName = “ping”; private String[] hosts = null; private String dataDir = “.”; private int step = 10; private String rrdPath = “”; private Timer timer = new Timer(); private long timeStart = 0; protected int width = 600; protected int height = 150; public PingMonitor(String[] hosts, String dataDir, int step) { this.hosts = hosts; this.dataDir = dataDir; this.step = step; this.rrdPath = this.dataDir + File.separator + monitorName + “.rrd”; } public String generateGraph() { long timeCur = org.jrobin.core.Util.getTimestamp(); return generateGraph(timeStart, timeCur); } public String generateGraph(long start, long end) { RrdDb rrdDb = null; try { Color[] colors = new Color[] { Color.GREEN, Color.BLUE, Color.MAGENTA, Color.YELLOW, Color.RED, Color.CYAN, Color.ORANGE, Color.PINK, Color.BLACK}; String graphPath = this.dataDir + File.separator + monitorName + “.png”; // create graph logger.info(”Creating graph”); RrdGraphDef gDef = new RrdGraphDef(); gDef.setWidth(width); gDef.setHeight(height); gDef.setFilename(graphPath); gDef.setStartTime(start); gDef.setEndTime(end); gDef.setTitle(”Ping 命令响应时间”); gDef.setVerticalLabel(”毫秒”); String[] dsNames = null; rrdDb = new RrdDb(rrdPath); dsNames = rrdDb.getDsNames(); for (int i = 0; i < dsNames.length; i++) { String dsName = dsNames[i]; String legend = dsName; if (legend == null || legend.equals(”")) legend = dsName; gDef.datasource(dsName, rrdPath, dsName, “AVERAGE”); gDef.line(dsName, colors[i % colors.length], legend, 2); gDef.gprint(dsName, “MIN”, dataFormat + ” Min”); gDef.gprint(dsName, “AVERAGE”, dataFormat + ” Avg”); gDef.gprint(dsName, “MAX”, dataFormat + ” Max”); gDef.gprint(dsName, “LAST”, dataFormat + ” Last\\r”); gDef.print(dsName, “MIN”, “min” + dsName + ” = %.3f”); gDef.print(dsName, “AVERAGE”, “avg” + dsName + ” = %.3f”); gDef.print(dsName, “MAX”, “max” + dsName + ” = %.3f”); gDef.print(dsName, “LAST”, “last” + dsName + ” = %.3f”); } gDef.setImageInfo(”<img src=’%s’ width=’%d’ height = ‘%d’>”); gDef.setPoolUsed(false); gDef.setImageFormat(”png”); gDef.setSmallFont(new Font(”Monospaced”, Font.PLAIN, 11)); gDef.setLargeFont(new Font(”SansSerif”, Font.BOLD, 14)); // gDef.setAltYMrtg(true); // create graph finally RrdGraph graph = new RrdGraph(gDef); // logger.info(graph.getRrdGraphInfo().dump()); logger.info(”Graph created”); return graph.getRrdGraphInfo().getFilename(); } catch (Exception e) { logger.warning(”Error in generating graph: ” + e.getMessage()); } finally { if (rrdDb != null) try { rrdDb.close(); } catch (IOException e) { e.printStackTrace(); } } return null; } private double getReplyTime(String[] strs) { double value = Double.NaN; if (strs != null) { for (int j = 0; j < strs.length; j++) { String str = strs[j]; int n1 = str.indexOf(”time=”); int n2 = str.indexOf(”ms”, n1); if (n1 > 0 && n2 > n1) { String s = str.substring(n1 + “time=”.length(), n2).trim(); try { value = Double.parseDouble(s); } catch (Exception e) { } break; } } } return value; } /** * Return a HashMap which contains the current value of each data source. * * @return the current value of each data source. */ public double getValue(String host) { String command = “”; String osName = System.getProperty(”os.name”); if (osName.indexOf(”Windows”) > -1) { command = “ping ” + host + ” -n 1″; } else { command = “ping ” + host + ” -c 1″; } return getReplyTime(execute(command)); } /** * Initialization. */ public void initialize() throws Exception { RrdDb rrdDb = null; try { rrdDb = new RrdDb(rrdPath); } catch (Exception e) { } if (rrdDb == null) { logger.info(”RRD data is not located in ” + rrdPath + “, create a new one”); RrdDef rrdDef = new RrdDef(rrdPath, timeStart - 1, step); for (int i = 0; i < hosts.length; i++) rrdDef .addDatasource(hosts[i], “GAUGE”, 2 * step, 0, Double.NaN); rrdDef.addArchive(”AVERAGE”, 0.5, 1, 24 * 3600 / step); rrdDef.addArchive(”AVERAGE”, 0.5, 300 / step, 7 * 288); logger.info(”Estimated file size: ” + rrdDef.getEstimatedSize()); rrdDb = new RrdDb(rrdDef); logger.info(”RRD file created.”); } logger.info(monitorName + ” RRD Db Defs: ” + rrdDb.getRrdDef().dump()); if (rrdDb != null) rrdDb.close(); } /** * Start monitor. * * @return true if succeed, else false. */ public boolean start() { logger.info(”start to monitor ” + monitorName); try { timeStart = org.jrobin.core.Util.getTimestamp(); initialize(); timer.scheduleAtFixedRate(new TimerTask() { public void run() { try { updateData(); } catch (Exception e) { e.printStackTrace(); logger.severe(”Timer running error: ” + e.getMessage()); } } }, 0, step * 1000); return true; } catch (Exception e) { e.printStackTrace(); } return false; } /** * Stop monitor. */ public void stop() { timer.cancel(); } private void updateData() throws Exception { RrdDb rrdDb = null; try { logger.info(”update rrd data for ” + monitorName); rrdDb = new RrdDb(rrdPath); String[] dsNames = rrdDb.getDsNames(); long lastUpdateTime = rrdDb.getLastUpdateTime(); long t = org.jrobin.core.Util.getTimestamp(); if (t > lastUpdateTime) { rrdDb.setInfo(”T=” + t); Sample sample = rrdDb.createSample(); sample.setTime(t); for (int i = 0; i < dsNames.length; i++) { String dsName = dsNames[i]; Double value = getValue(dsName); logger.fine(dsName + ” = ” + value); if (value == null) value = Double.NaN; sample.setValue(dsName, value); } sample.update(); } else { logger.warning(”Bad sample time ” + t + “(” + new Date(t * 1000L) + “)” + new Date() + “, the last update time was ” + lastUpdateTime + “(” + new Date(lastUpdateTime * 1000L) + “) - ” + monitorName); } } finally { if (rrdDb != null) try { rrdDb.close(); } catch (IOException e) { e.printStackTrace(); } } } public static void main(String[] args) { String[] hosts = new String[] { “ www.baidu.com “, “ www.google.cn ” }; PingMonitor p = new PingMonitor(hosts, “.”, 10); p.start(); try { Thread.sleep(10 * 60 * 1000); } catch (InterruptedException e) { e.printStackTrace(); } p.stop(); p.generateGraph(); } }