VITCTRL start option

   .-VITCTRL--=--BASE-.   
>>-+------------------+----------------------------------------><
   '-VITCTRL--=--FULL-'   

Specifies the level of control the VTAM® operator has for controlling the internal recording of certain default VTAM Internal Trace (VIT) options. By default, VTAM starts these VIT options: API, PIU, SSCP, MSG, NRM, PSS and CIO. The VITCTRL setting also controls the command processing of the DISPLAY TRACE command, and the MODIFY TRACE and MODIFY NOTRACE commands for TYPE=VTAM,MODE=INT.

You can change the value of VITCTRL with the MODIFY VTAMOPTS command while VTAM® is running. Changing the VITCTRL setting effects the processing of the next DISPLAY TRACE, MODIFY TRACE or MODIFY NOTRACE command but it has no effect on the current setting of the VIT options.

VITCTRL=BASE

Specifies that the operator cannot modify the settings of certain default VIT options using the MODIFY TRACE or the MODIFY NOTRACE commands or by start options for internal trace recording. This is the default value.

When VITCTRL=BASE is specified, VTAM manages the default VIT options as follows:

• The VIT options other than PSS remain active regardless of any other changes made with MODIFY TRACE, MODIFY NOTRACE or with the TRACE start option. The use of the PSS VIT option can be changed by the operator.
• Individual default options other than PSS are not listed in the DISPLAY TRACE output unless the user has explicitly activated the individual VIT options. The current setting of the PSS VIT option is always displayed in the DISPLAY TRACE command output.

VITCTRL=FULL

Specifies that the operator can modify the settings of all VIT options using the MODIFY TRACE and MODIFY NOTRACE commands or by start options for TYPE=VTAM,MODE=INT processing.

VTAM manages the default VIT options as follows:

• The operator can enable or disable one or more of the default VIT options using the MODIFY TRACE or MODIFY NOTRACE commands. This includes the MODIFY NOTRACE,OPT=ALL command which disables all VIT options, including the default options.
• When defining a CSDUMP message or code trigger, the VIT options that are contained in the option set STDOPTS (API, PIU, SSCP, MSG, NRM, CIO, and PSS) are enabled by default. When a CSDUMP message or code trigger is active, the VIT MSG option cannot be disabled by the MODIFY NOTRACE command.
• The current setting of the VIT options are always included in the DISPLAY TRACE command output.
• When activating any VIT option set, all of the options contained in the STDOPTS option set are also activated.

For more detail about the implications of the two levels of VIT control, see z/OS Communications Server: SNA Diagnosis Vol 2, FFST Dumps and the VIT.