z/OSMF log files

During normal operations, z/OSMF runtime data is created on the server (server side) or sent to the server by the client (client side). Both types of data are written to the z/OSMF log files.

Viewing the z/OSMF logs

The z/OSMF and WebSphere Liberty logs are available in the z/OSMF logs directory:

<USER_DIR>/data/logs/zosmfServer/logs

where the default for <USER_DIR> is /global/zosmf (with APAR PI92211) or /var/zosmf (without APAR PI92211).

The z/OSMF runtime log files are written in English only, and are tagged as ASCII, using the ISO8859-1 code page. You can view the log files in ASCII format through ISPF option 3.17, using the VA action (View an ASCII file). Other viewing options, such as OBROWSE, or tools such as vi, emacs, or grep, might require that you first convert the files to EBCDIC. If you want ASCII files to be converted to EBCDIC automatically when you browse them, set the z/OS® UNIX System Services environment variable _BPXK_AUTOCVT to "ON".

To access the logs, you require a user ID with z/OSMF administrator authority (that is, a user ID defined to the z/OSMF administrator group).

There are three ways to change logging levels and activate tracing:

Use the Set the z/OSMF logging level tab in the z/OSMF Diagnostic Assistant. For more information, see z/OSMF online help.
Use the IZUPRMxx parmlib member. For more information, see IZUPRMxx reference information.
Use the z/OS MVS MODIFY command. Note that the change persists only until the z/OSMF server is restarted.
In the following example, the command is entered from the system console and enables the finest level of logging for z/OSMF console services:
```
F server_name.logging='com.ibm.zoszmf.console.*=finest' 
```

z/OSMF diagnostic data is stored in the following log files. By checking these log files, you can locate any of the messages that are written by z/OSMF.

IZUGx.log

Contains the runtime messages, including the standard output and standard error streams from the JVM process.

The IZUGx.log files are contained in the following directory:

<USER_DIR>/data/logs

z/OSMF names the log files IZUGn.log, where n is a numeral in the range 0 - 9. z/OSMF creates log files in a "cascading" manner. The most current log file is always named IZUG0.log. When this log file reaches its predefined limit, z/OSMF saves it as IZUG1.log and begins writing to a new IZUG0.log file. When the IZUG0.log file is again full, z/OSMF saves it as IZUG1.log after it renames the existing IZUG1.log file to IZUG2.log. z/OSMF continues this process, saving each log file under the next available name, up to a maximum of ten log files. Thereafter, z/OSMF discards the oldest log file (IZUG9.log) whenever a new log file is to be created.

If the current IZUG0.log file becomes unavailable, z/OSMF writes its runtime data to the z/OSMF server logs directory (trace.log and messages.log) until the problem is resolved.

For examples of z/OSMF runtime log data, and a description of the log file format, see Examples of working with z/OSMF runtime logs.

FFDC log files

Contains the WebSphere Liberty first failure data capture (FFDC) log files. FFDC log files include the exception stack and optional additional data that is recorded when an unexpected exception occurs.

The FFDC log files are contained in the following directory:

<USER_DIR>/data/logs/zosmfServer/logs/ffdc

messages.log

Contains the WebSphere Liberty startup and runtime messages. Messages that are written to this file begin with CWW and include information such as the message time stamp and the ID of the thread that wrote the message. The messages.log does not contain messages that are written by the JVM process.

For example:

[9/6/13 20:52:21:569 GMT] 0000001f  
   com.ibm.ws.app.manager.internal.statemachine.StartAction A CWWKZ0001I:  
   Application IzuManagementFacilityWorkloadManagement started in 4.121  
   seconds.

The messages log is written to the following location:

<USER_DIR>/data/logs/zosmfServer/logs/messages.log

trace.log

Contains the same entries as found in messages.log. In addition, this file contains trace entries when additional tracing is enabled. This file does not contain messages that are written by the JVM process.

WebSphere Liberty defines this file as stderr. For example, JSSE tracing enabled with the z/OSMF advanced setting –Djavax.net.debug=all.

The trace log is written to the following location:

<USER_DIR>/data/logs/zosmfServer/logs/trace.log

Periodic maintenance of log files is recommended

It is recommended that you periodically review the following directories and remove files that are no longer needed. You can manage the removal of old log files by using the Space management tab in the z/OSMF Diagnostic Assistant. For more information, see z/OSMF online help.

<USER_DIR>/data/logs/zosmfServer: Contains the JVM-generated diagnostic files for Java exceptions, such as Java core, heap dump, snap.trc, and jit dump files.
<USER_DIR>/configuration: Contains the backup_configuration files.
<USER_DIR>/data/logs/zosmfServer/logs/ffdc: Might contain many log entries due to log rotation; additional file names with time stamps might be generated. The file names in this directory are created with a date and time stamp. For example: exception_summary_18.07.06_19.33.00.0.log

Managing log lock files

When z/OSMF initializes, the log file handler creates a file that is named IZUG0.log.lck. This file represents a "lock" on the log data. Usually, lock files are cleaned up automatically as part of application shutdown. However, if the z/OSMF server ends abnormally, the lock files might remain. If so, the log file handler appends numbers to the normal lock file name to find a file that is free.

If the z/OSMF server ends abnormally, inspect the log directory and delete the lock files. If more locks and log files were created, you can sort the files in the directory by time stamp to determine which files are the most recent. Back up these files if you want to preserve them, then clear the logs directory to conserve space.

If client data cannot be written to the server

If a communication problem prevents the client error log data from being written to the z/OSMF logs directory, the unlogged client data is displayed to the user in a separate browser window. This failover action allows for the client data to be retained until the communication with the z/OS system is restored. In some situations, IBM® Support might request this data for diagnostic purposes. If the browser window is closed, the client data is not retained.

Other z/OSMF log files

Do not confuse the z/OSMF runtime log file with the job log files that are created during the configuration process. In contrast to runtime data, configuration log data is written to a file in the z/OSMF user file system. If a problem occurs with the configuration log file, the log data is written instead to the directory specified by the /tmp parmlib statement.