PM28925: NEW FUNCTION

Obtain the fix for this APAR.

APAR status

• Closed as new function.

Error description

• New Function.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All users of DB2 10 for z/OS data sharing.   *
  ****************************************************************
  * PROBLEM DESCRIPTION: Data corruption may occur if DB2        *
  *                      structures in the coupling facilities   *
  *                      are not deleted prior to a group        *
  *                      restart.                                *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  In certain situations involving coupling facility problems
  and/or DB2 data sharing group outage, DB2 structures in CF could
  be corrupted.
  If the old CF structures are not manually deleted before a group
  restart, a problem may go undetected until objects are being
  processed. This could result in data corruption and may follow
  with different DB2 abends.
  

Problem conclusion

Temporary fix

Comments

• APAR PM28925 adds a new DB2 subsystem parameter
  DEL_CFSTRUCTS_ON_RESTART to DSN6SYSP. Users can optionally set
  this option if they want DB2 restart to attempt to delete the
  DB2 structures (SCA,IRLM lock structure and group buffers pools)
  in the coupling facility.  In a data sharing environment, the
  deletion of the structures will be successful only in the case
  where there are no other active connections.  If there are other
  active connections, the deletion will fail and restart will
  proceed normally. In a non-data sharing DB2 environment,
  any setting of DEL_CFSTRUCTS_ON_RESTART is ignored.
  
  Note:
      IRLM APAR PM31807 is also needed to be applied to get IRLM
      lock structure deleted in CF when DEL_CFSTRUCTS_ON_RESTART
      parameter is set to YES. Without the PM31807 fix, DB2 would
      attempt to delete only the group buffer pool(GBP) and the
      SCA structures with this option.
  
  
  Acceptable values for DEL_CFSTRUCTS_ON_RESTART are:
  
  - NO : DB2 restart will not attempt to delete
         the data sharing group's coupling
         facility structures.
         => This is the default setting
  
  - YES: DB2 restart will attempt to delete the
         structures during restart.  The delete
         will only be successful if there are no
         other DB2 subsystems connected to the
         structures at the time deletion is
         attempted.  If deletion is successful,
         the deleted structures will be recovered
         as necessary using the group restart or
         GRECP recovery process. This may increase
         the time DB2 restart takes to complete.
  
  DEL_CFSTRUCTS_ON_RESTART is meaningful only in the DB2 data
  sharing environment.  It cannot be changed online because
  the function is effective only during restart.
  
  For this function to work as intended, all members of a data
  sharing group need to have the same setting for
  DEL_CFSTRUCTS_ON_RESTART.
  
  The DEL_CFSTRUCTS_ON_RESTART setting can be specified in the
  DEL CF STRUCTS field on installation panel DSNTIPK.
  
  
  New DB2 and IRLM Messages:
      Messages will be issued by DB2 and IRLM to indicate that a
  CF structure was deleted because of the DEL_CFSTRUCTS_ON_RESTART
  parameter setting.  These messages are strictly informational
  and will not be issued if a CF structure deletion fails.
  
  DSNB316I csect-name GROUP BUFFER POOL gbpname DELETED BECAUSE OF
           SUBSYSTEM PARAMETER SETTING
  
  Explanation: Group buffer pool gbpname was deleted during DB2
  restart processing. This occurs when there are no other DB2
  subsystems connected to the group buffer pool listed in the
  message and when the DEL_CFSTRUCTS_ON_RESTART ZPARM indicates
  that DB2 should attempt to delete all group buffer pools.
  
  System action: The group buffer pool named in the message
  is deleted.
  
  
  DSN7003I csect-name SCA DELETED BECAUSE OF SUBSYSTEM PARAMETER
           SETTING
  
  Explanation: The DB2 Shared Communications Area (SCA) has been
  deleted because the DEL_CFSTRUCTS_ON_RESTART ZPARM indicated
  that DB2 restart should attempt to delete it.  The SCA will only
  be deleted if there are no other DB2 subsystems connected at the
  time deletion was attempted.
  
  System action: The SCA is deleted and rebuilt by DB2.
  
  
  DXR185I irlmx IXLFORCE SUCCESSFUL FOR IRLM LOCK
          STRUCTURE wwwwwwww
  
  Explanation: IRLM has deleted its lock structure due to a
  request made by the associated database subsystem.  If DB2 is
  the associated subsystem, lock structure deletion is done if the
  setting of the DEL_CFSTRUCTS_ON_RESTART ZPARM is YES.
  
  wwwwwwww Is the lock table name currently in use by the IRLM.
  
  System action: The lock structure is deleted and recovered by
  restart process.
  

APAR Information

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

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

  UK66376

Modules/Macros

• DSN@XAZP DSNB1PM2 DSNDQWPZ DSNDSYSP DSNFMDIR
  DSNF7DIR DSNF7DTA DSNTIDXA DSNTIDXB DSNTIJUZ DSNTINST DSNTIPK
  DSNTLIDE DSNTXAZH DSNTXAZP DSNWZIFA DSNZOVTB DSN6SYSP DSN7SINI
  

Fix information

• Fixed component name

  DB2 OS/390 & Z/

• Fixed component ID

  5740XYR00

Applicable component levels

• RA10 PSY UK66376

     UP11/04/17 P F104

Fix is available

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