PK30937: RECOVERY COMPLETES WITH RC=0 WHILE TIMESTAMP OF TYPE 06 LOG RECS ARE HEX ZEROES, THIS CAUSES DB TO SHOW BAD POINTERS WHEN PPC RUN

APAR status

• Closed as program error.

Error description

• Recovery completes with RC=0, Pointer Checker results in bad
  pointers when timestamp in has x'F0' at x'2C' of type 06 records
  .
  timestamp was never expected to have hex zeroes so a check for
  timestamp validity is not done. Some vendor products may place
  x'F0' in the timestamp so validity checking will need to be done
  .
  The x'f0' are the cause of the bad pointer records after a
  recovery run showing a RC=0
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All users of IMS DRF version 2 release 1     *
  *                 using tools, utilities, or local code        *
  *                 changes which interact with IMS logger       *
  *                 initialization or termination are affected.  *
  ****************************************************************
  * PROBLEM DESCRIPTION: During a PITR recovery, committed       *
  *                      updates may not be applied to the       *
  *                      target database if an invalid           *
  *                      timestamp in a type X'06' log record    *
  *                      is detected.  The result is a           *
  *                      corrupted database.                     *
  ****************************************************************
  * RECOMMENDATION: INSTALL CORRECTIVE SERVICE FOR APAR/PTF      *
  *                                                              *
  *                 When abend 385-A is encountered, look at the *
  *                 log record identified by the sequence number *
  *                 in the message and determine what is wrong   *
  *                 with the timestamp.                          *
  ****************************************************************
  Processing end of system type x06 log records with zeros in the
  ACPRILOG field caused all units of recovery (UOR) which are
  supposed to complete with the x06 record to be ignored.
  These UORs are reported in the UOR report at the end of recovery
  with elapsed time potentially greater than the total elapsed
  time of the subsystem.  DRF completes with a return code of zero
  even though all records that should have been are not applied.
  

Problem conclusion

• AIDS: RIDS/UTIL RIDS/DBS DBS/UTIL
    DEP: NONE
    GEN:
  
  *** END IMS KEYWORDS ***
  DOCUMENTATION CHANGE FOR APAR PK30937
  THIS MAINTENANCE IS BEING HELD SO YOU WILL BE
  AWARE OF DOCUMENTATION CHANGE TO MANUAL(S):
  SC18701603
  -
  THE FOLLOWING TEXT DESCRIBES THE DOC CHANGE:
  -
  A change has been made in IBM IMS Database Recovery Facility
  for z/OS, User's Guide and Reference, Version 2 Release 1,
  at page 87, chapter 7: IMS Database Recovery Facility Messages
  and Codes.
  
  FRD2892I     reason IN LOG RECORD seqnum DETECTED IN dsname
  
  Explanation: An invalid record contents is detected for the log
  data set with the dsname during database data set recovery by
  the IMS Database Recovery Facility.  The message destination is
  the z/OS system console and the IMS master terminal. If the
  message is issued in batch mode, the message destination is the
  z/OS system console. The message is followed by an ABEND 385-00A
  
  reason:      Identified the problem and is one of the following:
               Invalid time stamp
  seqnum:      The sequence number that identifies the log record
               in the log data set. It can be used to determine
               which record is bad.
  dsname:      The data set from which the log record was read.
  User Action: Examine the log record identified in the message
               within the log data set listed in the message.
               Use the IMS DFSLOG06 macro mapping of the log
               record to determine the offset to the ACPRILOG
               field. If this time stamp is zero, determine
               if anything in your environment interacts with the
               IMS Logger component initialization or termination
               processing. If not, report this problem to IBM.
               In any case, use the appropriate tool or procedure
               to place the prilog time for the subsystem or batch
               job which created the log in the ACPRILOG field of
               the log record. Refer to the appropriate IMS
               documentation  for the format of the prilog time
               stamp for the 06 log record.  Make sure the
               06 log records at the beginning and end of the log
               data set have the time stamp provided.
  
  System Action: The IMS Database Recovery Facility address space
               terminates.
  Module:      FRXRBUF0
  -
  FRXRBUF0 is modified to check the time tamp for a type x06
  log record.  If the time stamp is zero, MSG FRD2892I is
  issued and recovery is abnormally terminated with ABENDU385
  RSN00A.
  
  FRXRVGB is changed to provide a flag to ensure that only one
  read instance abends.
  
  FRXBDMG0 and FRXMTC are changed to add MSGFRD2892I.
  

Temporary fix

Comments

APAR Information

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

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

  UK18150

Modules/Macros

• FRXBDMG0 FRXMTC   FRXRBUF0 FRXRVGB
  

Fix information

• Fixed component name

  IMS DB RECOVERY

• Fixed component ID

  5655I4400

Applicable component levels

• R210 PSY UK18150

     UP06/09/22 P F609