PH25111: IN RARE CASES CUSTOMERS MAY EXPERIENCE REPEATED RESTARTS OF INTEGRATED SYNCHRONIZATION WHICH MAY SUSPEND THE SUBSCRIPTION.

APAR status

• Closed as documentation error.

Error description

• In rare cases customers may experience repeated restarts of
  Integrated Synchronization which may suspend the subscription.
  Subsequently, the subscription will be reported as in ERROR.
  DSNX881I messages with the following content may occur
  even if the replication has been running successfully before:
  message:    "Dumped error log stream to file
               2020-04-23T06:32:48.555_dump_1.db2zlog"
  time:       "2020-04-23T06:32:48.559Z"
  severity:   WARNING
  originator: "ApplyServerInstance"
  
  message:    "Thread LogParserThread threw an exception which was
               not caught"
  time:       "2020-04-23T06:32:48.559Z"
  severity:   ERROR
  originator: "TerminatingUncaughtExceptionHandler"
  
  In the trace the following error string my be shown:
  2020-04-23 06:33:25 SEVERE
  dwa.replication.apply.utilities.TerminatingUncaughtExceptionHand
  ler uncaughtException: Thread LogParserThread threw an exception
  which was not caught
   java.lang.AssertionError: invalid column length read from the
  column offset arrays: 0. Length must not exceed column
  precision: 128
  
  The issue affects IDAA V7 maintenance levels 7.5.0.x and 7.5.1.
  It occurs when the value of a key column has a length of 0.
  Integrated Synchronization (InSync) will enter a loop and
  finally suspend; the steps of the loop are:
  1) Failure showing the messages listed above
  2) Restart InSync process
  3) Failure with the same messages
  4) After four retries to restart InSync it will be finally
  suspendend.
  Customer will not be able to get InSync out of this state
  again and needs IBM support to clear the situation.
  A fix will be delivered with maintenance level 7.5.2.
  
  Contact IBM support to clean up the system and apply a
  configuration that avoids the occurrence of this is issue.
  
  Additional Keywords:
  InSync TS003626660 RTC#24734
  

Local fix

• To prevent the occurrence of the issue, avoid replication of
  tables
  with empty values in the Key columns, for example:
  avoid "" as value of a varchar key column.
  
  If the issue already occurred, proceed as follows to get the
  subscription up and running again:
  1.DisableReplicationForDatabaseSystem /
  EnableReplicationForDatabaseSystem (if reloads are acceptable).
  However, the issue may reoccur if rows with empty Key columns
  are replicated.
  2. Disable affected tables:
   2a Determine which tables are affected by the issue
      (this can be done by checking replicated-tables.json along
      with the dumped .dbz2log).
   2b Set affected tables to state ERROR in replicated-tables.json
   2c Remove suspension marker (file name SUSPENDED).
   2d If you have removed all affected tables, replication will
      continue for the tables not affected.
  

Problem summary

• The corresponding program code responsible for handling of key
  columns was corrected accordingly.
  The fix is part of maintenance level 7.5.2.
  

Problem conclusion

• Upgrade the accelerator maintenance level to 7.5.2 or higher.
  

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:

Fix information

Applicable component levels