I cannot connect the JRockit Mission Control Client to the JVM. What could be the problem?

Consider the following:

• (JDK 1.4) Have you started the management server?

  You must starte the management server if you want to enable your application for remote monitoring or if you want to monitor an instance of a JRockit JVM running with JDK 1.4. You can start the management server by adding the -Xmanagement option to your Java command line. For more information, see http://edocs.bea.com/jrockit/jrdocs/refman/optionX.html#wp1030433. Secure Socket Layer (SSL) and authentication are available in JDK 1.5/1.6 and will be enabled by default. If you do not want to set up certificates, SSL and authentication can be disabled by providing ssl=false and authenticate=false. Also, if you want to use the remote discovery feature of JRockit, you can enable it by setting autodiscovery=true; for example:

  java -Xmanagement:ssl=false,authenticate=false,autodiscovery=true

  You can also start the management server on an already running JRockit JVM by using the jrcmd utility available in the JROCKIT_HOME/bin directory. For more information, see http://edocs.bea.com/jrockit/geninfo/diagnos/ctrlbreakhndlr.html#wp1000350 .

• Are you using the correct protocol?

  Ensure that you are using the same version of the JRockit JVM that you want to monitor as is being used by the JRockit JVM running the JRockit Mission Control Client. If that is not an option, you can use the radio buttons in the connection dialog box in JRockit Mission Control to select the correct protocol for the JDK version of the JVM to which you want to connect: 1.4 will select RMP and 1.5 and later will select JMXRMI.

  For earlier versions of the JRockit Mission Control Client, these radio buttons don't exist. In these versions, to make a 1.5 JRockit JVM instance connect to a 1.4 version, you must explicitly specify the JMX Service URL. The format of the service URL is:

  service:jmx:rmp://<hostname>:<port>

  for example:

  service:jmx:rmp://localhost:7091

• Are the correct ports opened?

  Note that running JMX over RMI requires two ports and that one of the ports will not be known beforehand. For more information, see "JRockit Mission Control Communications" in the Introduction to JRockit Mission Control on the Oracle Technology Network..

• Is the communication caught in a firewall?

  For more information, see "JRockit Mission Control Communications" in the Introduction to JRockit Mission Control on the Oracle Technology Network.