Web Hosting - Java/Tomcat - Developer Troubleshooting and Logs

Best Practices

• Plan your logging strategy during development and deployment and do not rely solely on default logging libraries.  Customize logging for your application’s requirements.

• Log errors and warnings within your application rather than relying on Tomcat logs. Apache HTTP logs only indicate that an error occurred and do not provide application specific details.

• Server-level logs, such as Catalina output, won’t include your application-specific logs.  We are not logging standard input and output into Catalina; this is your responsibility.

Handle Exceptions Properly:

• Prevent uncaught exceptions from escaping your application.
  
  
• Implement a top-level try-catch block for comprehensive error handling.

Adjust logging levels and Debugging

• Increase logging levels based on environment e.g. Production logging for severe errors to trace issues not seen in development or testing.

• Considering adding top level error handling code which can log errors and warnings to your web application logs as a more appropriate location than tomcat log.

Java customers have real-time access to Apache and Tomcat logs through two methods:

1. Plesk Log Viewer

• Log in to the Plesk Control Panel for your domain.
• Open Logs icon from the dashboard
  • View real-time logs and archives for:
    • Apache Access Logs
    • Apache Error Logs

  • A Custom log file can be added from your website directory to the log viewer. In the log manager select Manage Log Files --> Add Custom Log --> Select the file and click OK.

  • For example, navigate to tomcat/logs -> select something like catalina.out, manager.<date>.log, <appname>.log, localhost.<date>.log or localhost_access_log.<date>.txt

2. Secure FTP and SSH

• Connect using your provided hostname, username, and password.
• Navigate to the /logs folder.
• Open the /tomcat folder.

3. Plesk File Manager

• Log in to the Plesk Control Panel for your domain.
• Open File Manager icon from the dashboard
• Navigate to the /logs folder.
• Open the /tomcat folder.

• Apache WebServer (read-only) Configuration Availability
• Restarting Tomcat Server
• Access to Tomcat Manager
• Tomcat Documentation

For questions or advice on Java/Tomcat logging strategies, contact the Web Hosting Team: webhosting@doit.wisc.edu