Some Java virtual machines (JVMs) enable remote monitoring. This note explains how to enable this feature on the Sun HotSpot JVM, versions 1.5 and 1.6, using either the jstatd daemon or Java Management Extensions (JMX).

Remote Monitoring via the jstatd Daemon

This technique requires that you have the jstatd daemon running on the same machine as the target JVM. Once the daemon is running, it listens on a specified port. That port must be available to the remote monitoring tool.

To start the jstatd daemon, follow these steps:

1. Create a permissions policy (for example, jstatd.all.policy) that contains the following contents:
grant codebase "file:${java.home}/../lib/tools.jar" { permission java.security.AllPermission; };
2. Start the jstatd daemon, and specify the policy file and the port that you want to use. The daemon is found in the Java Development Kit (JDK) bin directory. Note: The location for that directory depends on the operating environment.
• For UNIX operating environments, specify the following:
  JAVA_HOME/bin/jstatd -p 1199 -J-Djava.security.policy=jstatd.all.policy
• For Windows operating environments, specify the following:
  JAVA_HOME\bin\jstatd -p 1199 -J-Djava.security.policy=jstatd.all.policy

Remote Monitoring via JMX

To monitor a Java virtual machine (JVM) via JMX, follow these steps:

1. Add the following arguments to the target JVM:
   -Dcom.sun.management.jmxremote.authenticate=false -Dcom.sun.management.jmxremote.ssl=false -Dcom.sun.management.jmxremote.port=3333
2. Restart the JVM so that the new arguments take effect.
3. Verify that the JMX port (3333 in this example) is open and listening. Once you verify that the port is open and listening, you can connect to the port for remote monitoring.

Operating System and Release Information