IC63373: DB2 CONFIGURATION PARAMETER NUM_LOG_SPAN DOES NOT GET UPDATED CORRECTLY WHEN THE ACTIVELOGSIZE IS CHANGED IN DSMSERV.OPT

IBM Tivoli Storage Manager V6.1 Fix Pack 3 (6.1.3) Server Downloads

APAR status

• Closed as program error.

Error description

• If in the Tivoli Storage Manager server options file dsmserv.opt
  the size of the active log (ACTIIVELOGSIZE) is changed,
  the DB2 configuration parameter NUM_LOG_SPAN does not get
  updated correctly.
  
  The NUM_LOG_SPAN setting is used by Tivoli Storage Manager to
  manage how much of  the active log a transaction can span.
  This value should represent 90% of the number of primary log
  files (LOGPRIMARY) which each is be default 512MB in size.
  
  So for the default Tivoli Storage Manager active log size of
  2GB, 4 primary log volumes are used and Tivoli Storage Manager
  sets NUM_LOG_SPAN to 90% of this size (3 volumes).  When the
  size of the active log (ACTIIVELOGSIZE) is increased in the
  dsmserv.opt file, the NUM_LOG_SPAN is not updated to represent
  90% of the new log size in DB2. This can cause in the worst case
  a crash of the Tivoli Storage Manager server in case of a long
  running transaction which spans over more volumes than allowed
  by the NUM_LOG_SPAN value.
  
  
  Tivoli Storage Manager Versions Affected:
  6.1.2.0 Servers on all platforms
  
  
  Initial Impact:
  Medium
  
  
  Additional Keywords:
  zz61 TSM 52852 IC60975 crash transactionlog
  
  | MDVPARTL 6.1.2.0 |
  

Local fix

• The work around is to manually calculate 90% of the log size and
  update the db2 database to correctly set NUM_LOG_SPAN.
  
  Calculate correct value of NUM_LOG_SPAN (each log size is fixed
  at 512MB):
  1. Take the new value of activelogsize in dsmserv.opt in and
  divide that by 512MB. This value is the total number of log
  volumes reflected in db2 value LOGPRIMARY.
  2. Multiple LOGPRIMARY by 90%. This value should be reflected in
  NUM_LOG_SPAN.
  
  (alternate method involving slightly less arithmetic)
  Calculate correct value of NUM_LOG_SPAN:
  1. Use the following db2 command to determine the number of log
  volumes used:
     db2 get db cfg for TSMDB1
  2. Multiply the value for the LOGPRIMARY parameter by 90%.  This
  value should be reflected in NUM_LOG_SPAN.
  
  Update NUM_LOG_SPAN by issuing the following db2 command:
  db2 update db cfg for TSMDB1 using NUM_LOG_SPAN <newValue>
  You may need to restart the TSM server, which will restart the
  db2 database as well.
  

Problem summary

• ****************************************************************
  * USERS AFFECTED: All Tivoli Storage Manager V6.1 servers      *
  *                 users.                                       *
  ****************************************************************
  * PROBLEM DESCRIPTION: See ERROR DESCRIPTION.                  *
  ****************************************************************
  * RECOMMENDATION: Apply fixing level when available. This      *
  *                 problem is currently projected to be fixed   *
  *                 in level 6.1.3. Note that this is            *
  *                 subject to change at the discretion of IBM.  *
  ****************************************************************
  *
  

Problem conclusion

• This problem was fixed.
  

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

• Fixed component name

  TSM SERVER

• Fixed component ID

  5698ISMSV

Applicable component levels

• R61A PSY

     UP

• R61H PSY

     UP

• R61L PSY

     UP

• R61S PSY

     UP

• R61W PSY

     UP