IT28733: MQ V5.3 FOR NONSTOP WMQTRIG SCRIPT LEADS TO UNPREDICTABE TRIGGERING RESULT DUE TO HANDLING OF PARAM FILE.

APAR status

• Closed as program error.

Error description

• The mqtrig (or wmqtrig in WebSphere MQ) is  an IBM MQ script
  that is used to trigger Guardian programs and TACL commands or
  scripts. The flow of actions goes as follow:
  - The script creates a param file,
  - The script calls gtacl,
  - gtacl reads the param file, and creates an environment from
  the param file content and starts the Guardian application with
  that environment.
  There is a possibility when the script appends another
  enviroment to an existing param file. That leads to
  unpredictable triggering results or no triggering at all.
  

Local fix

Problem summary

•   Under certain conditions the MQ trigger script
  reuses an existing gtacl environment file. The MQ trigger script
  appends the trigger related environment variables, configured by
  the user, at the end of the file.
  The old content of the gtacl environment file gets not deleted.
  The user application to be started by the MQ trigger script runs
  with these environment variables.
  When an user application, triggered by MQ, shows unexpected
  behaviour that can be related to it's environment variables,
  this should be taken into account as being the root cause.
  

Problem conclusion

•  The MQ trigger must create an empty gtacl
  environment file.
  In order to prevent the reuse of an existing environment file,
  a timestamp has to be part of the file name.
  

Temporary fix

•  Check for existing /tmp/gtaclx.PID files where a
  process with that PID does not exist anymore.
  Delete these files.
  

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

Fix information

• Fixed component name

  WEBS MQ NSS ITA

• Fixed component ID

  5724A3902

Applicable component levels