Troubleshooting Tomcat Issues

The following issues might arise during the Web UI installation and testing process.

Another Web server (or other process) uses port 8080.

By default, Tomcat attempts to bind to port 8080 at startup. To change this value, open <CATALINA_HOME>\conf\server.xml, and search for 8080. Change that number to a port (higher than 1024) that is not in use. Save your changes and restart Tomcat.

The Tomcat server fails to start due to port conflicts, or because another Tomcat instance is already running.

When the Tomcat server starts, it binds two ports (HTTP and Server Shutdown), which are configurable in <CATALINA_HOME>\conf\server.xml. These bindings prevent more than one instance of the Tomcat server from starting unless each instance is configured to run on a separate port. The details of configuring multiple Tomcat server instances are beyond the scope of this document.

The Tomcat application tries to use the wrong JRE/JDK.

(Windows users) Follow these instructions to set the default JRE or JDK:

  1. Right-click the Tomcat icon in the taskbar, and choose Configure from the menu.

    The Configuration dialog box appears.

  2. Navigate to the Java tab on the Configuration dialog box, and select the Use default checkbox.
  3. Click OK to save the change.

(Linux users) Check that the jre_home (if using the JRE) or java_home (if using the full JDK) environment variable indicates the version specified inSetting Up the Java Environment.