?????? jvisualvm是Jdk自带的，具体点，据说是jdk1.6-07后加到jdk中的。本地监控很简单，在JAVA_HOME/bin中打开jvisualvm即可，所有本机的java程序会自动列出来。我们来说下远程监控的问题。

????? ?当然网上有很多相关资料，我就把我实践的结果列出来吧。

???????????? ?环境， 本地: WIN-XP sp3, jdk1.6.0_17 远端：CentOS5.1, jdk1.6.0_3

?????

????? 具体步骤如下，

????? ?1. 启动远端jstatd.

????????? ?1.1 配置[b]java[/b]安全访问，将如下的代码存为文件 jstatd.all.policy (名字随便起)，但要放到JAVA_HOME/bin中，其内容如下，

??? ?????? ?grant codebase"file:${java.home}/../lib/tools.jar"{ permission java.security.AllPermission; };

?????????? 1.2 进入到JAVA_HOME/bin中，执行./jstatd -J-Djava.security.policy=jstatd.all.policy?

?????? 注：这时候能启动正常，但是后面本地用 jvisualvm的时候抛异常，

java.net.ConnectException: Connection refused: connect
	at java.net.PlainSocketImpl.socketConnect(Native Method)
	at java.net.PlainSocketImpl.doConnect(PlainSocketImpl.java:333)
	at java.net.PlainSocketImpl.connectToAddress(PlainSocketImpl.java:195)
	at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:182)
	at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:366)
	at java.net.Socket.connect(Socket.java:519)
	at java.net.Socket.connect(Socket.java:469)
	at java.net.Socket.<init>(Socket.java:366)
	at java.net.Socket.<init>(Socket.java:180)
	at sun.rmi.transport.proxy.RMIDirectSocketFactory.createSocket(RMIDirectSocketFactory.java:22)
	at sun.rmi.transport.proxy.RMIMasterSocketFactory.createSocket(RMIMasterSocketFactory.java:128)
	at sun.rmi.transport.tcp.TCPEndpoint.newSocket(TCPEndpoint.java:595)
Caused: java.rmi.ConnectException: Connection refused to host: 127.0.0.1; nested exception is: 
	java.net.ConnectException: Connection refused: connect
	at sun.rmi.transport.tcp.TCPEndpoint.newSocket(TCPEndpoint.java:601)
	at sun.rmi.transport.tcp.TCPChannel.createConnection(TCPChannel.java:198)
	at sun.rmi.transport.tcp.TCPChannel.newConnection(TCPChannel.java:184)
	at sun.rmi.server.UnicastRef.invoke(UnicastRef.java:110)
	at java.rmi.server.RemoteObjectInvocationHandler.invokeRemoteMethod(RemoteObjectInvocationHandler.java:178)
	at java.rmi.server.RemoteObjectInvocationHandler.invoke(RemoteObjectInvocationHandler.java:132)
	at $Proxy7.activeVms(Unknown Source)
	at sun.jvmstat.perfdata.monitor.protocol.rmi.RemoteVmManager.activeVms(RemoteVmManager.java:82)
Caused: sun.jvmstat.monitor.MonitorException: Error communicating with remote host: Connection refused to host: 127.0.0.1; nested exception is: 
	java.net.ConnectException: Connection refused: connect
	at sun.jvmstat.perfdata.monitor.protocol.rmi.RemoteVmManager.activeVms(RemoteVmManager.java:85)
	at sun.jvmstat.perfdata.monitor.protocol.rmi.MonitoredHostProvider.activeVms(MonitoredHostProvider.java:217)
	at com.sun.tools.visualvm.jvmstat.application.JvmstatApplicationProvider.processNewHost(JvmstatApplicationProvider.java:126)
	at com.sun.tools.visualvm.jvmstat.application.JvmstatApplicationProvider.access$000(JvmstatApplicationProvider.java:69)
	at com.sun.tools.visualvm.jvmstat.application.JvmstatApplicationProvider$5$1.run(JvmstatApplicationProvider.java:276)
	at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:572)
[catch] at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:997)
==>

?

??????? 据查，有两种方法解决，一种是把 /etc/hosts中的ip改成实际的IP,然后重启网络，但我用此法没有解决问题。另一种是，在jstatd后加hostname的参数，如下，

??