PK19397: IMS CONNECT 9.1 DOES NOT CONNECT TO THE RIGHT TCP/IP STACK

APAR status

• Closed as program error.

Error description

• Customer has the following environment:
  z/OS 1.4, IMS 9.1 and IMS Connect 9.1
  Customer has two TCP/IP stacks: TCPIP and TCPIP2
  The TCPIP statement in the IMS Connect config file specifies
  HOSTNAME=TCPIP2.  But IMS Connect does *not* connect to the
  TCPIP2 stack. Instead it connects to the stack called TCPIP.
  Furthermore, IMS Connect puts out the HWS0780I message saying
  that IMS Connect has connected to the TCPIP2 stack (when in
  reality it has not).
  After reviewing the code in HWSSDOPN & HWSSDOTD, here's where
  the problem lies:
  For z/OS 1.4 or higher, IMS Connect 9.1 does not issue the
  INITAPI macro where HOSTNAME (TCP/IP Jobname)is specified.
  Instead it uses the USS API to specify the maximum number of
  sockets descriptors but it doesn't use the USS API to specify
  the stack affinity. And so the value of the HOSTNAME parameter
  is not used to specify the stack affinity. There is no
  indication that the INITAPI macro is going away with z/OS 1.4 or
  higher. So IMS Connect should either:
  1) Go back to using the INITAPI macro  OR
  2) Specify stack affinity using USS API.
     In USS API, the stack affinity is specified with the pfsctl
  callable service with the PC#SetIbmOptCmd function.
  *
  Incidently this customer did not experience this problem in
  IMS Connect 1.2. Now in IMS Connect 1.2 we also don't issue the
  INITAPI macro but only if IPV6=Y is specified in the config file
  The customer has IPV6=N & so the INITAPI macro is issued and
  that is why the customer did not encounter this problem in 1.2
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All IMS V9 IMS Connect users of common INET  *
  *                 (CINET) configuration with multiple TCP/IP   *
  *                 (socket transport) stacks.                   *
  ****************************************************************
  * PROBLEM DESCRIPTION: IMS Connect does not establish affinity *
  *                      to the TCP/IP transport stack specified *
  *                      on the IMS Connect configuration file   *
  *                      TCPIP statement HOSTNAME= parameter.    *
  *                                                              *
  *                      Message HWSS0780I indicating that TCIP  *
  *                      connection was successful to the TCP/IP *
  *                      stack named in HOSTNAME= parameter when *
  *                      connection to that stack was not        *
  *                      established.                            *
  *                                                              *
  *                      Forward-fit of PK01143                  *
  ****************************************************************
  * RECOMMENDATION: INSTALL CORRECTIVE SERVICE FOR APAR/PTF      *
  ****************************************************************
  When IMS Connect runs in a Common Internet (CINET) environment
  at z/OS 1.4 or higher, IMS Connect establishes connections to
  TCP/IP transport stack servers without establishing affinity to
  the specific stack specified by the user on the IMS Connect
  configuration file TCPIP statement HOSTNAME= parm.  However, IMS
  Connects sends message HWSS0780 indicating connection was made
  to the TCP/IP stack specified for hostname.  Attachment to the
  stack is made based on the CINET default stack information in
  the BPXPRMxx SYS1.PARMLIB member.
  

Problem conclusion

• AIDS: RIDS/DCS RIDS/LMGR DCS LMGR
    DEP: NONE
    GEN:
  POSTREQ PK25103
  
  *** END IMS KEYWORDS ***
  This maintenance affects IMS V9 IMS Connect z/OS 1.4 (and
  higher) configured in a Common Internet (CINET) environment.
  
  Part HWSXSH30 has been modified to make a Unix System Services
  (USS) Physical File System (PFSCTL) call with command option
  PC#SetIbmOptCmd to attempt to establish persistent address space
  affinity to the particular socket transport (TCP/IP stack)
  associated with the jobname indicated on the IMS Connect
  configuration file member TCPIP statement HOSTNAME= parameter.
  
  If for some reason attachment to the specified stack is not
  successful logic modified in HWSSDOPN insures that message
  HWSS0785W is issued to notify of the failure.
  
  To prevent TCP/IP transport stack affinity specify no parm in
  the HOSTNAME= parameter field (e.g. HOSTNAME=,) of the IMS
  Connect configuration file TCPIP statement.  Attachment is
  determined based on the SUBFILESYSTYPE definitions of BPXPRMxx
  proclib member.  The HOSTNAME field in the HWSS0780I message
  will contain blanks.
  
  If the HOSTNAME= parameter is incorrect (e.g. misspelled or is
  not an existing TCPIP stack jobname) attachment is determined
  based on the SUBFILESYSTYPE definitions of the BPXPRMxx
  SYS1.PROCLIB member with affinity to no specific stack.  The
  Hostname displayed in the the HWSS0780I message is replaced with
  new default hostname 'HWS$$TCP' to indicate the default TCP/IP
  stack attachment.
  
  Environments where just one TCP/IP stack exist are not affected
  as the PFSCTL has no affect. IMS Connect will always connect to
  the single stack regardless of the HOSTNAME= parameter of the
  TCPIP IMS Configuration file statement.
  
  DOCUMENTATION UPDATE:
  
  IMS V9 IMS Connect Guide and Reference (SC18-9287-xx) Chapter 17
  IMS Connect Error Codes and Messages.
  
  Message HWSS0780I message text modified as such:
  
  HWSS0780I TCPIP COMMUNICATION ON HOSTNAME=hostname OPENED; M=mc
  
  In the message text:
  
  *  If "hostname" is the TCP/IP JOBNAME, IMS Connect has affinity
     to the single transport (TCP/IP stack) identified by TCP/IP
     JOBNAME.
  
  *  If "hostname" is blank, IMS Connect uses any active transport
     (TCP/IP stack) in the CINET environment.
  
  *  If "hostname" is HWS$$TCP, an invalid TCP/IP JOBNAME is
     specified in the HOSTNAME= keyword of the TCP/IP
     configuration statement.
  
  *  IMS Connect uses any active transport (TCP/IP stack) in the
     CINET environment.
  
  mc identifies the module issuing the message.
  
  Module: SOC1 -- HWSSOC10
  
  System Action:  This message is issued during IMS Connect
  startup and whenever communication is established with the
  TCP/IP communication facility.
  

Temporary fix

Comments

• REPINNED RP06/05/16 (ATXT) TO ADD POSTREQ PK25103 INFO.
   **** PE06/05/16 PTF IN ERROR. SEE APAR PK25103 FOR DESCRIPTION
  
  ×**** PE06/05/16 FIX IN ERROR. SEE APAR PK25103  FOR DESCRIPTION
  

APAR Information

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

  PK01143

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

  UK12989

Modules/Macros

• HWSSDOPN HWSXSH30
  

Fix information

• Fixed component name

  IMS V9

• Fixed component ID

  5655J3800

Applicable component levels

• R900 PSY UK12989

     UP06/04/03 P F603