Tuesday, June 20, 2017

Red Alert : CICS TS for z/OS V5.3 - Unpredictable results when identical Unit Of Work ID (UOWID) passed to multiple CICS subsystems

Yesterday, IBM issued a Red Alert on CICS V5.3. Here's the info. I'm just taking over the text from the Red Alert.

Users Affected:

Users of CICS Transaction Server for z/OS V5.3 who are using any kind of subsystem that CICS connects to such as:
  • DB2
  • IBM
  • WebSphere MQ
  • Coupling Facility Data Tables (CFDT)
  • Shared Temporary Storage Server
  • Named Counter Server
  • Vendors like Oracle


Two or more CICS tasks obtain the same Unit Of Work ID (UOWID) and pass the ID to the respective subsystem. The subsystem may then experience unpredictable results because it thinks that it is being called out of sequence for just one unit of work. APAR PI82188 describes symptoms that have been observed, such as CICS DB2 applications abend or CICS CFDT records become locked due to two CICS tasks passing non-unique Unit Of Work IDs. However, this can affect any CICS subsystem, not just DB2 and CFDT. Please see APAR PI82188 for additional information.

Recommended Actions:

Apply PTF UI47871 for CICS TS for z/OS V5.3 APAR PI82188 as soon as possible to prevent unpredictable results.

If you haven't signed up to the Red Alerts by now, you really should do it. Just go over here.