Enabling dynamic tracing of LDAP client library code

Before Version 8.0.0, Fix Pack 14, it was not possible to switch the LDAP client trace on and off without also stopping or starting the queue manager.

From Version 8.0.0, Fix Pack 14, you can switch LDAP client trace on with the strmqtrc command and off with the endmqtrc command without needing to stop or start the queue manager. To enable this behavior, it is also necessary to set an environment variable AMQ_LDAP_TRACE to a non-null value.

When the AMQ_LDAP_TRACE is set to a non-null value, and the LDAP functionality is used, some queue manager processes create zero length files under /var/mqm/trace. When the trace is then switched on using the strmqtrc command, some trace information is written to these files. Later, when trace is switched off with the endmqtrc command, trace information ceases to be written to the files, but handles to the files remain open until the queue manager ends.

On UNIX platforms, filesystem space cannot be released completely simply by unlinking these files with the rm command. This is a side-effect from the fact that the handles remain open. Therefore, a queue manager end should be performed, whenever disk space in /var/mqm/trace needs to be released.