PK71276: OTMA CM0 ALTPCB ISRT MADE BY SHARED QUEUES BACKEND IFP REGION FROM CM1 INPUT HAS INVALID OTMA PREFIX LENGTH.

APAR status

• Closed as program error.

Error description

• Customer application running in IFP region with OTMA CM1 input
  message does a message switch via an ALTPCB to an OTMA CM0
  destination. This works in a shared queues environment if
  the IFP region runs on the Front End IMS. It fails if the
  transaction is cross queue ( runs on a Back End IMS ).
  Customer is not using SuperMember but the target OTMA
  member is active on the BE IMS where application runs.
  The problem is the OTMA prefix built for the CM0 ISRT is built
  with a bad length. The length extends beyond the CNTRL/STATE/
  SECURITY/USERDATA lengths. As a result when send to IMS
  connect there is no application data ( since the LL is zero ).
  The problem is that FP doesn't pass the USERDATA to FINDDEST
  and it doesn't exist on backend IMS. The length calculation
  is therefore wrong.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All IMS V9 OTMA users in a shared queues     *
  *                 environment with AOS=Y and Fast Path.        *
  ****************************************************************
  * PROBLEM DESCRIPTION: Invalid OTMA prefix length when ALTPCB  *
  *                      output from an IFP region is generated  *
  *                      on a backend IMS system.                *
  ****************************************************************
  * RECOMMENDATION: INSTALL CORRECTIVE SERVICE FOR APAR/PTF      *
  ****************************************************************
  When a fast path transaction, running on a backend IMS system in
  a shared queues environment, does an ALTPCB insert to an OTMA
  destination, the OTMA prefix length is miscalculated, resulting
  in no application data available to the client.
  
  Fast path transactions do not pass OTMA user data to the backend
  IMS system. When an ALTPCB insert is done to an OTMA destination
  the user data is built by the OTMA Destination Resolution Exit,
  DFSYDRU0, and the length is added to the OTMA prefix length.
  However, the OTMA prefix length already includes the length of
  the original user data from the input message. This causes the
  offset to the application data to be incorrect and when the
  message is sent to the client, the application data is not
  found.
  
  OTMA has two variable length sections in the OTMA prefix,
  security data and user data. These sections are rebuilt on a
  BE IMS system during fast path GU. However, fast path does not
  pass the length of these sections to the backend IMS, therefore
  OTMA miscalculates the OTMA prefix length.
  

Problem conclusion

• GEN:
  KEYWORDS:
   SYSPLEXSQ
  
  *** END IMS KEYWORDS ***
  OTMA fast path processing was modified to pass the length of
  the inputting security data and user data so that the correct
  adjustments can be made on the backend IMS when calculating the
  OTMA prefix length.
  
  DBFEMHB was modified to add two fields which will be used to
  store the OTMA security data length and user data length.
  
  DFS62DLA was modified to add a new field which will contain the
  address of the stored OTMA security data length and user data
  length.
  
  DFSLUMIF was modified to add new parm for function TIBINFO
  requesting OTMA to store the security data length and user data
  length.
  
  DBFHIEL0 was modified to add the new DFSLUMIF parm to the
  TIBINFO call.
  
  DFSYLUS0 was modified to store the OTMA security data length
  and user data length when processing the TIBINFO call, and to
  retrieve the OTMA security data length and user data length
  when processing the fast path GU call, and adjust the OTMA
  prefix length accordingly.
  

Temporary fix

• *********
  * HIPER *
  *********
  

Comments

APAR Information

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

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

  PK79035 PK79036 UK44223

Modules/Macros

• DBFEMHB  DBFHIEL0 DFSLUMIF DFSYLUS0 DFS62DLA
  

Fix information

• Fixed component name

  IMS V9

• Fixed component ID

  5655J3800

Applicable component levels

• R900 PSY UK44223

     UP09/02/26 P F902 Ž