DBRC internal trace

DBRC internal trace is a useful tool for diagnosing problems that are possibly related to DBRC. The trace is always enabled.

Types of problems DBRC internal trace can diagnose

The DBRC internal trace can help diagnose many different types of problems, such as:

  • RECON data set contention
  • RECON data set errors that are indicated by messages
  • System abends in which the PSW is pointing to DBRC
  • DBRC abends
  • Whether DBRC or some other IMS component is causing the problem

Sometimes a problem occurs as a result of the interaction between two different modules performing different tasks. Interpreting trace entries is the best way to determine what each module was doing and when. For example, for RECON data set errors, it is important to know which DBRC modules manipulated the RECON data set and when.

You generally look at the DBRC trace output under the direction of an IBM® Software Support representative, who will guide you in collecting data in specific trace fields and in interpreting that data. The DBRC trace entries that follow help you interpret trace data.

Example of DBRC internal trace

A user receives abend code xxx. The PSW is pointing to DBRC. The user reports the problem to an IBM support representative. Some of the steps that the user diagnostician might take under the guidance of the IBM representative are:

  1. Locate the DBRC trace in the trace using the TRACETBL eye catcher.
  2. Use the sample trace to verify that you have found the trace and to help you navigate through the trace table entries.
  3. Find DBRC and IMS control blocks and data areas by using addresses from selected trace table entries.
  4. Determine the events that occurred before the abend.
  5. Use the information in the trace and data areas to understand what caused the abend.

Some DBRC functions have the capability of generating additional trace entries that can aid in problem analysis. An IBM representative can assist you in enabling one or more of these expanded trace options through the use of the CHANGE.RECON command.

The CHANGE.RECON command supports a TRACEOPT parameter that allows you, under the direction of an IBM representative, to select expanded DBRC trace options.

Figure 0. CHANGE.RECON
Read syntax diagramSkip visual syntax diagramTRACEOPT( n( ,m...))
n,m,...
DBRC TRACEOPT options

TRACEOPT is an optional parameter that you use only under the direction of an IBM Software Support representative for the purpose of gathering documentation for problem analysis. The IBM Software Support will provide the sub-options for the TRACEOPT parameter.