When trying to troubleshoot a particularly difficult problem, there is a often need to increase logging. However, as a side effect of running logs with verbose logging, it can be very time consuming to filter through all of the messages in the log. Many of the messages may be unrelated to the process, which can further increase the amount of time it takes to find the source of the issue. Thankfully, there is a capability within WebLogic Server that allows us to get a better idea of what's happening when there is an issue in SOA or OSB without needing to completely overload the log files with unnecessary information.

To access Selective Tracing, expand the WebLogic Domain folder when you log in to Fusion Middleware Control and right-click on the target domain. A menu will pop up, as shown in the following figure, where you need to navigate to Logs | Selective Tracing:

Figure 9.10: The domain menu showing the path to Selective Tracing

Once the selective tracing page has loaded, you will be presented with a form asking for Application Name, Level, Duration, Trace ID, and Description. It also provides the ability to add fields. In order to trace a composite, there are only a couple of modifications needed. First, set Duration to whichever length is necessary for tracing purposes. If possible, make the tracing duration minimal because if you do so, there are less logs to dredge through and it will have less of an impact on performance. This may be exceptionally critical when dealing with a production system. Next, adjust the Level used to the desired setting; once again, this setting will vastly affect the amount of logs collected during the tracing. Any other settings can be adjusted as desired; however, one last field must be set to effectively trace a single composite.

To specify a particular composite, click on Add Fields and check the box next to Composite Name. Click on the Add button. Type the name of the composite into the Composite Name field, as demonstrated in Figure 9.11. The name should not consist of a revision, so if there is a HelloWorld [1.0] window deployed, then only the title HelloWorld should be typed in the field. Finally, click on Start Tracing to begin the selective trace.

Figure 9.11: The Tracing Options menu

To view the information on the current trace, click on Active Traces and Tracing History. This will provide you with a list of the active and historical traces. This will allow you to disable active traces if relevant information has already been gathered. By clicking on the Trace ID for any given trace, the log messages pertaining only to the trace will be visible.

While this example has only referenced SOA Suite, this can be used for any application on a domain and can be filtered by any of the fields available.