MQ Trace on Java MQ Clients

 I find it very difficult to debug the Java client application written for MQ. Most of the error messages are self explanatory but some of the error messages are difficult to diagnose and find the cause. Enable tracing would really help to identify the root of the problem. In this post, we will see how to enable tracing on Java applications.

MQ Trace

Simple MQ Trace enabling can be done by adding a JVM parameter like this

java -Dcom.ibm.mq.commonservices=trace.properties ...

Create trace.properties with the following attributes

Diagnostics.MQ=enabled
Diagnostics.Java=explorer,wmqjavaclasses,all
Diagnostics.Java.Trace.Detail=high
Diagnostics.Java.Trace.Destination.File=enabled
Diagnostics.Java.Trace.Destination.Console=disabled
Diagnostics.Java.Trace.Destination.Pathname=/tmp/trace
Diagnostics.Java.FFDC.Destination.Pathname=/tmp/FFDC
Diagnostics.Java.Errors.Destination.Filename=/tmp/errors/AMQJERR.LOG

oints to be noted

• Add libraries of IBM JRE (From the directory $JRE_HOME/lib) to CLASSPATH
• Create the directories /tmp/FFDC, /tmp/trace and /tmp/errors
• Add read permission to trace.properties
• Keep an eye on the log file size and make sure to disable logging when not required. Otherwise, it will keep filling the disk space. (Logs size will become some gigs in few hours easily)

-Djavax.net.debug=true

-Djavax.net.debug=ssl:handshake