The VTAM® program
provides several kinds of traces to record the flow of network events.
Each trace occurs at a different point in the network (see Figure 1). This difference allows you to narrow
down the problem by following a request/response unit (RU) through
the network and determining where in the network the RU is incorrect.
(The RU could be out of sequence or lost, the data in the RU could
have been changed, and so on.)
This topic includes the following information:
- Activating network traces
- Starting the generalized trace facility (GTF)
- Formatting and printing trace records
- Trace output
- The APPN route selection trace shows the flow of information throughout
the APPN session setup route selection process. See APPN route selection trace for more information
- VTAM traces and their results:
- The buffer contents trace shows the contents of inbound and outbound
message buffers. See Buffer contents trace for
more information.
- The I/O trace shows (in order) all I/O sent between VTAM and a particular network resource. See I/O trace for more information.
- The QDIOSYNC trace is used to synchronize host and OSA-Express2
or later diagnostic data. See QDIOSYNC trace for
more information.
- The resource state trace creates VTAM internal
trace (VIT) entries when the current state or desired state, or both,
of a resource for which tracing has been requested changes. See Resource state trace for more information.
- The session management exit (SME) buffer trace shows the input
and output of the session management exit (SME) ISTEXCAA. See Session management exit (SME) buffer trace for more information.
- The SMS (buffer use) trace shows information about the use of
buffers, including how often a buffer pool has expanded, how many
buffers are currently being used, and what was the maximum number
of buffers used since the last trace record was written. See SMS (buffer use) trace for more information.
- The TGET/TPUT trace shows each message as it passes between a
TSO command processor and TSO/VTAM. See TGET/TPUT trace for TSO/VTAM for
more information.
Figure 1. Network traces provided by VTAM