PH01925: DFHSO0002 A SEVERE ERROR (CODE X'0CAB') HAS OCCURRED IN MODULE DFHSOLS

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• You are getting this DFHSO0002 dump unexpectedly. In the trace
  in the dump you notice that there is a CSOL task running on
  the SL TCB that is getting this '0CAB' exception repeatedly:
  
  SL SO 0CAB SOLS *EXC* SIOCTTLSCTL_ERROR -1,120,77B70291
  SL SO 0CAB SOLS *EXC* SIOCTTLSCTL_ERROR -1,120,77B70291
  SL SO 0CAB SOLS *EXC* SIOCTTLSCTL_ERROR -1,120,77B70291
  SL SO 0CAB SOLS *EXC* SIOCTTLSCTL_ERROR -1,120,77B70291
  SL SO 0CAB SOLS *EXC* SIOCTTLSCTL_ERROR -1,120,77B70291
  SL SO 0CAB SOLS *EXC* SIOCTTLSCTL_ERROR -1,120,77B70291
  SL SO 0CAB SOLS *EXC* SIOCTTLSCTL_ERROR 2097152,422,00000000
  
  SIOCTTLSCTL is the call made by CICS to AT-TLS to
  find out the state of the connection. The final SO 0CAB
  exception trace entry is what led to the dump
  being taken.
  
  The dump is a direct result of the changes made by PI87515.
  That APAR added code to handle an EINTR return value from the
  SIOCTTLSCTL call. If EINTR is returned then a maximum of 5
  further calls are made.  This is done in the hope that the next
  call works and does not also get interrupted (EINTR).
  
  If the call fails all 6 times then a severe error, DFHSO0002 is
  issued and the connection is closed.  The connection has to be
  closed because CICS cannot obtain all the TLS related
  information about that connection.  lacking that information
  would adversely affect subsequent CICS processing of that
  request.
  
  The error handling of the SIOCTTLSCTL failures needs
  to be improved.  CICS clearly cannot assume that EINTR is a
  retryable error.  The system dump is perhaps too severe a
  reaction and the exception trace entries being produced are not
  as helpful as they could be.  CICS should have a new message
  specifically for this failure that provides the TCPIPSERVICE
  name and the IP address of the partner system along with the
  failure return and reason codes.
  
  Additional Symptom(s) Search Keyword(s): KIXREVxxx
  

Local fix

• N/A
  

Problem summary

• ****************************************************************
  * USERS AFFECTED: All.                                         *
  ****************************************************************
  * PROBLEM DESCRIPTION: Exception trace SO 0CAB followed by     *
  *                      DFHSO0002 message lacks diagnostics.    *
  ****************************************************************
  In the reported problem, the Socket Listener task ( CSOL )
  made a UNIX SIOCTTLSCTL call to ATTLS to establish the state
  of the connection.  The call failed with an EINTR ( interrupt ).
  The call was retried but they all failed, CICS then made an
  SO 0CAB exception trace entry followed by a DFHSO0002 message.
  The captured diagnostics could be better at identifying the
  underlying cause.
  

Problem conclusion

• DFHSOLS has been amended to provide additional and improved
  diagnostics when the aforementioned SIOCTTLSCTL call fails.
  
  The CICS Transaction Server 5.4 Knowledge Centre will be
  updated thus:
  
  Trace entry SO 0CAB will be changed to:
  
  Point ID Module   Lvl   Type                 Data
  SO 0CAB  DFHSOLS  Exc   SIOCTTLSCTL Failure  1 BPX1IOC
                                               2 LTE
                                               3 EXBZTLSP
                                               4 Socket object
                                               5 Tcpipservice name
                                               6 Client IP address
  
  Message DFHSO1002 will be added:
  
  DFHSO1002 date time applid  CICS is unable to determine the
  secure state of a new connection received on ATTLSAWARE
  TCPIPSERVICE: tcpipservice from Client IP address: clientaddr.
  UNIX System Services values returned are
  bpx_return_value(bpx_return_value),
  bpx_return_code(bpx_return_code) and
  bpx_reason_code(X'bpx_reason_code').
  
  Explanation: A web client attempted to connect to a CICS region
  which is secured by an Application Transparent Transport Layer
  Security (AT-TLS) aware TCPIPSERVICE. The socket listener task
  (CSOL) made a UNIX BPXIOCTL call to obtain information relating
  to a new connection but the call failed.
  
  SystemAction: An exception trace entry is made in the trace
  table. No system dump is taken, unless specifically requested
  in the dump table. CICS continues unless the dump table
  specifies that CICS should terminate.
  The socket accepted for the client is closed.
  
  User response: Refer to the z/OS UNIX System Services Messages
  and Codes manual to determine the cause of the error.
  
  Module: DFHSOLS
  
  In addition, the data type for the insert for bpx_reason_code
  in message DFHSO0130 will be changed from decimal to hex.
  Similarly the data type for the insert bpx_return_code in
  message DFHSO1000 will be changed from hex to decimal.
  

Temporary fix

Comments

• ×**** PE19/04/11 FIX IN ERROR. SEE APAR PH10947  FOR DESCRIPTION
  

APAR Information

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

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

  UI59537

Modules/Macros

• DFHMESOC DFHMESOE DFHMESOK DFHSOLS  DFHSOTRI
  

Fix information

• Fixed component name

  CICS TS Z/OS V5

• Fixed component ID

  5655Y0400

Applicable component levels

• R100 PSY UI59537

     UP18/11/15 P F811

Fix is available

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