Configure first failure data capture log file purges
The first failure data capture (FFDC) log file saves information that is generated from a processing failure. These files are deleted after a maximum number of days has passed. The captured data is saved in a log file for analyzing the problem.
The first failure data capture (FFDC) feature preserves the information that is generated from a processing failure and returns control to the affected engines. The captured data is saved in a log file for analyzing the problem. FFDC is intended primarily for use by IBM Support. FFDC instantly collects events and errors that occur during the product run time. The information is captured as it occurs and is written to a log file that can be analyzed by IBM Support personnel.
FFDC is intended primarily for use by IBM Support. FFDC instantly collects events and errors that occur during the product run time. The information is captured as it occurs and is written to a log file that can be analyzed by IBM Support. The data is uniquely identified for the servant region that produced the exception.
The log file purges in seven days by default. If we are concerned about the amount of disk space used by the FFDC log files, we can configure the days between purges.
The FFDC configuration properties files are located in the properties directory under the Application Server product installation. Set the ExceptionFileMaximumAge property to the same value in all three files: ffdcRun.properties, ffdcStart.properties, and ffdcStop.properties. We can set the ExceptionFileMaximumAge property to configure the days between purging the FFDC log files. The value of the ExceptionFileMaximumAge property must be a positive number. The FFDC feature does not affect the performance of the Application Server product.
To configure the number of days between the FFDC log file purges. The value is in days.
- Open the ffdcRun.properties file.
The file is located in the app_server_root/properties directory.
The file is located in the profile_root/properties directory.
- Change the value for the ExceptionFileMaximumAge property to the number of days between the FFDC log file purges. The value of the ExceptionFileMaximumAge property must be a positive number. The default is seven days. For example, ExceptionFileMaximumAge = 3 sets the default time to three days. The FFDC log file is purged after three days.
- Save the ffdcRun.properties file and exit.
- Repeat the previous steps to modify the ffdcStart.properties and ffdcStop.properties files.
Results
The FFDC file management function removes the FFDC log files that have reached the maximum age and generates a message in the SystemOut.log file.
This topic references one or more of the application server log files. As a recommended alternative, we can configure the server to use the High Performance Extensible Logging (HPEL) log and trace infrastructure instead of using SystemOut.log , SystemErr.log, trace.log, and activity.log files on distributed and IBM i systems. We can also use HPEL in conjunction with the native z/OS logging facilities. If we are using HPEL, we can access all of the log and trace information using the LogViewer command-line tool from the server profile bin directory. See the information about using HPEL to troubleshoot applications for more information on using HPEL.
The FFDC file management function removes the FFDC log files that have reached the maximum age and generates a message in the SYSOUT of the server job log.
Related tasks
Use High Performance Extensible Logging to troubleshoot applications Work with troubleshooting tools