Troubleshooting using JVM logs
To start troubleshooting a problem, check the JVM log files first. These log files collect output for the System.out and System.err output streams for the application server process. One log file is specified for the SystemOut.log output stream and one file specified for the SystemErr.log output stream.
An application can write print data to the JVM logs either directly in the form of System.out.print() or System.err.print() method calls or by calling a JVM function, such as Exception.printStackTrace(). In addition, the System.out JVM log contains system message events written by the WebSphere® Application Server. In the case of a IBM® WebSphere Application Server Network Deployment configuration, JVM logs are also created for the deployment manager and each node manager, since they also represent JVMs.
- SystemOut.log is more useful monitoring the health of the running application server but can help in determining a problem, although it's better to use the IBM Service log and the advanced capabilities of the Log Analyzer to determine a problem.
- SystemErr.log contains exception stack trace information that is useful when performing problem analysis.
The JVM log files are self-managing to the extent that they can be configured not to grow beyond a certain size. Also, you can set how many historical, or archived, files to keep and which of the log files to rollover or archive based by time or size or both.
1. In the Integrated Solutions Console, click Troubleshooting --> Logs and Trace.
2. Click the Sametime Advanced server name.
3. Under General Properties, click JVM Logs.
Note: Any configuration changes to the JVM logs that are made to a running Sametime Advanced server do not take effect until you restart the server. Any log and trace settings that you change in the Runtime tab take effect without restarting, but do not take effect once you restart – unless you also made those changes in the Configuration tab.
4. To configure or change a log setting, use the settings on the Configuration tab.
5. To view the output of the logs, click the Runtime
tab, then click View.