Set up the error log

WebSphere Application Server for z/OS uses an error log to record error information when an unexpected condition or failure is detected within the product's own code. We can use the log stream to record activity and help diagnose problems.

Unexpected conditions or failures include:

• Assertion failures

• Unrecoverable error conditions

• Failures related to vital resources, such as memory

• Operating system exceptions

• Programming defects in WebSphere Application Server for z/OS code.

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.

• Because WebSphere Application Server for z/OS is predefined as a z/OS system logger application, we can use a log stream as the product's error log. By doing so, we can direct error information to a coupling facility log stream, which provides sysplex-wide error logging, or to a DASD-only log stream, which provides single system-only error logging.

• We can set up a common log stream for all WebSphere Application Server for z/OS servers, or individual log streams for each application server. Local z/OS client ORBs can also log data in log streams. The system logger APIs are unauthorized, but log stream resources can be protected using security products such as RACF .

• We can use the WebSphere variable ras_time_local to control whether timestamps in the error log appear in local time (ras_time_local=1) or Greenwich Mean Time (GMT)(ras_time_local=0), which is the default.

• For additional information about z/OS log stream requirements, access the z/OS MVS™ Setting up a Sysplex, SA22-7625 available on the z/OS Library web page

Log output destinations and characteristics

Manage operator message routing