How to activate and deactivate Datacom VSAM Transparency in CICS regions

Products

• Datacom
• DATACOM - AD

Issue/Introduction

When working with Datacom VSAM Transparency (called VT), there may be an occasion when it is necessary to turn of this functionality within a particular CICS region, without interrupting other work in that region.

This article explains how to disable VT processing in CICS, and then how to enable it again.

 

 

Resolution

To deactivate VT in a running CICS Region, first close the online URTs for the VT databases (DBOC CLOSE transaction), and then issue the CICS transaction:
DVMT DEACT=$CAVT

After issuing this transaction, you should receive a list of the various VSAM file entries, and their status, similar to this:
DVX0006I 'CUSTMR ' FILE IS NOW DEACTIVATED

Following the list of files, you should receive a message that indicates that VT is turned off:
DVX0002I ONLINE VSAM TRANSPARENCY IS NOW DEACTIVATED
DVX0018I TRANSACTION COMPLETED

To activate VT again manually issue the CICS transaction:
DVMT ACT=$CAVT

After issuing this transaction, you should receive a list of the various VSAM file entries, and their status, similar to this:
DVX0005I 'CUSTMR ' FILE IS NOW ACTIVATED

Following the list of files, you should receive a message that indicates that VT is active:
DVX0001I ONLINE VSAM TRANSPARENCY IS NOW ACTIVATED
DVX0018I TRANSACTION COMPLETED

To check the status of VT, issue this CICS transaction:
DVMT INQ=STATUS

This will return one of these messages indicating the status of VT operation:

DVX0003I ONLINE VSAM TRANSPARENCY IS ACTIVATED

DVX0004I ONLINE VSAM TRANSPARENCY IS DEACTIVATED

DVX0034I ONLINE VSAM TRANSPARENCY IS UNAVAILABLE

This "unavailable" message above indicates that VT was not activated automatically at CICS startup and has not been manually activated.