Solution

Modify the domain.xml file to remove the address attribute from the -Xrunjdwp option in the java-config element for the cluster. This results in the JVM choosing a random debug port for the instance. The port number chosen for the instance is displayed in the server log when it is started; for example:

• Before:

  debug-options="-Xdebug -Xrunjdwp:transport=dt_socket,server=y,
  suspend=n,address=9009"

• After:

  debug-options="-Xdebug -Xrunjdwp:transport=dt_socket,server=y,
  suspend=n"