PH21816: HANG AT SHUTDOWN. CLS1 TASK IN ALLOCATE SUSPEND

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• CICS Shutdown hangs due to a CLS1 transaction suspended
  for a privileged ALLOCATE wait.
    This happens when the only session bound
  for an LU62 (APPC) Connection SNASVCMG modegroup
  is the Secondary Contention Loser.
    The ZISP ENTRY FACILITY_REQ LU6.2_ALLOCATE
  in the trace does ZLOC ENTRY LOCATE requests
  for all sessions.  But, it does not chose the bound session.
  .
    This could happen any time the VTAM ACB is closed
  and CICS needs to DRAIN the APPC modegroups to zero.
  .
    This may happen if the Connection has Limited Resource
  set for its own Contention Winner SNASVCMG session,
  but the ConLos session does not.  So, the ConWin session
  is RELEASED but the ConLos session is ACQUIRED.
  .
  Additional Symptom(s) Search Keyword(s): KIXREVxxx
  LR TCTE_LR TCSE_LR
  

Local fix

• Change the network to remove to cause of the limited resource.
  That will allow the ConWin session to remain bound
  and it will be allocated when needed.
  

Problem summary

• ****************************************************************
  * USERS AFFECTED: All CICS users.                              *
  ****************************************************************
  * PROBLEM DESCRIPTION: CLS1 suspends indefinitely with         *
  *                      resource type ALLOCATE when the VTAM    *
  *                      ACB is closed.                          *
  ****************************************************************
  This problem of CLS1 remaining in an ALLOCATE SUSPEND can occur
  during shutdown and following a CEMT SET VTAM CLOSED.
  It arises when the primary contention winner session for an LU62
  (APPC) SNASVCMG modegroup is unbound when CICS is attempting to
  send a Change Number of Sessions (CNOS) request to the partner
  to set the parallel session number to zero.
  
  This may happen because the sessions are defined as being
  Limited Resources or because an operator has taken action to
  unbind sessions.
  
  The ALLOCATE is not allowed because CICS has set the TCTVVTHO
  flag to indicate that an orderly close of VTAM is in progress.
  

Problem conclusion

• CICS is changed so that the CNOS to zero is issued before flag
  TCTVVTHO is set if the SNASVCMG winner session for the
  connection is not bound.
  

Temporary fix

Comments

• ×**** PE21/10/28 FIX IN ERROR. SEE APAR PH41654  FOR DESCRIPTION
  

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

  010PC2Ÿ UI71609 UI71610 UI71611

Modules/Macros

• DFHEIPSH DFHEIQVT DFHZATI  DFHZCLS  DFHZCPLR DFHZISP  DFHZNAC
  DFHZOPA  DFHZRAC
  

Fix information

• Fixed component name

  CICS TS Z/OS V5

• Fixed component ID

  5655Y0400

Applicable component levels

• R100 PSY UI71611

     UP20/09/24 P F009

• R200 PSY UI71610

     UP20/09/24 P F009

• R300 PSY UI71609

     UP20/09/24 P F009

Fix is available

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