Tips for troubleshooting mediations

Use this set of specific tips to help troubleshoot problems with mediations.

To help identify and resolve problems, use the Troubleshooter reference: Messages. It contains information about error messages, indexed by message prefix. For each message there is an explanation of the problem, and details of any action that we can take to resolve the problem.

For information about looking at error logs, see Use basic or traditional message logs to troubleshoot applications.

Tips for common problems

• Where is my message?

• How do I enable trace?

• Why was my message not mediated?

• Why does my mediation not run?

• Which error messages relate to mediations?

Where is my message?

If the message is not where you expect it to be, check the following:

• The message had the reliability level Best effort nonpersistent, and has been discarded as a result of constrained system resources. For more information, see Reliability levels.

• The message has been received by another consumer, and has gone from the system.

• The message expiry time has exceeded, and the message has been discarded.

• The mediation returned false, and the message has been discarded. For more information, see Programming mediations.

• The mediation threw an exception, and the message was sent to the exception destination. For more information, see Error handling in mediations.

• The destination to which the message was forwarded has been deleted, and the message has been sent to the exception destination. For more information, see Exception destinations and Error handling in mediations.

• The forward routing path has been modified to behave other than intended, and the message has not been routed to the intended destination. For more information, see Configuring a destination forward routing path.

• There is an implicit loop in the forward routing path, and the message has not arrived at the intended destination.

How do I enable trace?

For more information, see Work with trace.

Why was my message not mediated?

• Check if the destination is mediated. To do this, list the mediation points for the destination. For more information, see Listing mediation points for a bus destination.

• Look in the system.out log for the following error message:
  CWSIZ0002E: The mediation named {0} that is attached to destination {1} is defined to use mediation handler list {2}. However this handler list does not exist.

  Check for the following common reasons why the handler list does not exist:

  • The application containing the handler list has not been installed.

  • The application containing the handler list has not been started.

  • The name of the handler list is mis-spelled in the mediation definition.

• Check the status of the mediation handler application in the administrative console. If it has the status Stopped, check for error messages in the system.out log.

• Check that the message matches the selector and/or discriminator configured on the mediation. To do this:

  1. View the message on the mediation point. For more information, see View messages for a bus destination.

  2. Check the configuration for the mediated destination. For more information, see Configuring mediation properties.

Why does my mediation not run?

If your mediation does not run, check the following:

• The status of the mediation in the administrative console.

• The stop reason on the mediation point. For more information, see restarting a mediation that has stopped on error.

• Error messages in system.out log. For more information, see Use basic or traditional message logs to troubleshoot applications.

Which error messages relate to mediations?

Mediations error messages have the following prefixes:

CWSJU

Errors about message production or consumption.

CWSIZ

Errors about what has happened to the message when it was mediated.

Related concepts

Exception destinations

Related tasks

Restarting a mediation that has stopped on error Reference topic