Error logs

 

Overview

WebSphere MQ uses a number of error logs to capture messages concerning its own operation of WebSphere MQ, any queue managers that you start, and error data coming from the channels that are in use.

The location of the error logs depends on whether the queue manager name is known and whether the error is associated with a client.

  1. If the queue manager name is known and the queue manager is available, error logs are located in:
    /var/mqm/qmgrs/queuename/errors

  2. If the queue manager is not available, error logs are located in:
    /var/mqm/qmgrs/@SYSTEM/errors

  3. If an error has occurred with a client application, error logs are located on the client's root drive in:
    /var/mqm/errors

 

Log files

At installation time an @SYSTEM errors subdirectory is created in the qmgrs file path. The errors subdirectory can contain up to three error log files named:

  • AMQERR01.LOG
  • AMQERR02.LOG
  • AMQERR03.LOG

After you have created a queue manager, it creates three error log files when it needs them. These files have the same names as the @SYSTEM ones, that is AMQERR01, AMQERR02, and AMQERR03, and each has a capacity of 256 KB. The files are placed in the errors subdirectory of each queue manager that you create.

As error messages are generated, they are placed in AMQERR01. When AMQERR01 gets bigger than 256 KB it is copied to AMQERR02. Before the copy, AMQERR02 is copied to AMQERR03.LOG. The previous contents, if any, of AMQERR03 are discarded.

The latest error messages are thus always placed in AMQERR01, the other files being used to maintain a history of error messages.

All messages relating to channels are also placed in the appropriate queue manager's errors files, unless the queue manager is unavailable, or its name is unknown, when channel-related messages are placed in the @SYSTEM errors subdirectory.

To examine the contents of any error log file, use your usual system editor.

 

Early errors

There are a number of special cases where these error logs have not yet been established and an error occurs. WebSphere MQ attempts to record any such errors in an error log. The location of the log depends on how much of a queue manager has been established.

If, because of a corrupt configuration file for example, no location information can be determined, errors are logged to an errors directory that is created at installation time on the root directory (/var/mqm).

If WebSphere MQ can read its configuration information, and can access the value for the Default Prefix, errors are logged in the errors subdirectory of the directory identified by the Default Prefix attribute.

 

Operator messages

Operator messages identify normal errors, typically caused directly by users doing things like using parameters that are not valid on a command. Operator messages are national-language enabled, with message catalogs installed in standard locations.

These messages are written to the associated window, if any. In addition, some operator messages are written to the AMQERR01.LOG file in the queue manager directory, and others to the @SYSTEM directory copy of the error log.

 

WebSphere is a trademark of the IBM Corporation in the United States, other countries, or both.

 

IBM is a trademark of the IBM Corporation in the United States, other countries, or both.