JVM log files

The JVM log files are one of the first places to start when troubleshooting a problem. These log files contain the output for the System.out and System.err output streams for the application server process. There is one log file specified for the System.out output stream and one file specified for the System.err output stream. The JVM logs contain print data written by applications. The data may be written directly by the application in the form of System.out.print(), System.err.print(), etc, method calls. Data may also be written indirectly by the application calling a JVM function, such as Exception.printStackTrace(). In addition, the System.out JVM log contains system messages (also known as message events) written by the WebSphere application server.

The JVM log files are self-managing in that you can configure the files to not grow beyond a certain size, and you can configure the number of historical, or archived, files to retain. In addition, you can configure the log files to rollover (be archived) based on time as well as size.

The granted authorities for the files are:

*PUBLIC	*EXCLUDE
QEJBSVR	*RW

If your application server is running under a user profile other than the default (QEJBSVR) and that user profile does not have QEJBSVR specified as a group profile, explicitly grant *RW authority to the user profile for the activity.log file.

Depending on how the JVM log is configured, application print data may be formatted to look like WebSphere system messages, or may be displayed as plain text with no additional formatting. WebSphere system messages are always formatted.

Refer to these topics for more information on configuring and using the JVM log files.

Configure the JVM log files
This topic describes how you can use the administrative console to change the name, size, number of files kept, and location for the JVM logs.

View the JVM log files
This topic describes the methods available for viewing the contents of the JVM logs.

Interpret the contents of the JVM log files
This topic describes the format of the information that is written to the JVM logs.