Turning Developer Traces On and Off 
You can turn developer traces on and off and set the trace level dynamically from within the SAP System or with system profile parameters or command-line arguments.
Activating / Deactivating Developer Traces from within SAP System:
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1. Choose Administration ® System Management ® Monitor ® System Monitoring ® Process Overview. (Alternatively, enter transaction SM50).
2. Choose the work process(es) in which you wish to increase the trace level.
3. Choose Process ® Trace ® Active components.
The system presents a dialog screen that shows the current status of the developer trace.
Turn developer tracing on and off for different server components by selecting the appropriate checkboxes.
4. Set the degree of detail by entering a number in the Level field. Possible trace levels are as follows:
¡ 0: No trace
¡ 1: Write error messages in the trace file.
¡ 2: Full trace. The trace entries that are actually written can vary with the program that is being traced.
¡ 3: Additionally, trace data blocks.
Activating / Deactivating Developer Traces from the System Profile:
You can also set trace options instance-wide with the rdisp/TRACE=<n> option. The trace values are the same as those in the list above.
Setting the trace parameter in the instance profile of a particular server activates developer traces only in that server.
Setting the parameter in the default profile would activate traces in all servers (excepting those whose instance profiles specify a different parameter value).
Activating and Deactivating Developer Traces from the Command Line:
You can also manage the tracing using appropriate commands in the command line. This is possible in all SAP programs. Typically, you must add these options to the start commands for SAP processes in the start-up profile of an instance of your SAP system. For information on editing see the documentation on the Computing Center Management System Guide (CCMS).
The following criteria are available:
· TRACE=0: No trace
· TRACE=1: Write error messages in the trace file.
· TRACE=2: Full trace. The trace entries that are actually written can vary with the ABAP program that is being traced.
· TRACE=3: Additionally, trace data blocks.
Next Steps
You can then view the traces in the system or at operating system level, or download them to your local computer. The sections below contain more details: