Log Parallelism must be off for 9i or Real Application Clusters (RAC) databases

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Replication will fail to start

Diagnosing the problem

Run the following command: show parameter log_parallelism;

Oracle 9i: log_parallelism integer N
Oracle 10g: _log_parallelism_max integer N
NOTE: In Oracle 10g, the above command might not return anything, meaning that the _log_parallelism_max internal parameter was not set by the database administrator. You should run the following command as sysdba since the tables require special permissions.

select x.ksppinm name, y.ksppstvl value from x$ksppi x , x$ksppcv y where x.indx = y.indx and x.ksppinm = '_log_parallelism_max'

The result would look like this: _log_parallelism_max N
If the value of N is 1, log parallelism is disabled; and n > 1 means that is enabled

Resolving the problem

In Oracle 9i, RAC environments and Transformation Server for Oracle versions prior to 6.0 SP2, Log Parallelism must be disabled by following this procedure:

  • 1)Shutdown the database instance.
  • 2)Run the following command to disable log parallelism:
    Oracle 9i:
    SQL> alter system set log_parallelism=1 scope=spfile;
    Oracle 10g:
    SQL> alter system set "_log_parallelism_max"=1 scope=spfile;
  • 3)Restart the database instance.
  • 4)Check if the parameter was set correctly by running the command from diagnosing the problem.
  • If this a RAC environment then run steps 1 through 4 for each database instance (node) in RAC.

Product Alias/Synonym

Transformation Server For Oracle
Transformation Server

Document information

More support for:

InfoSphere Change Data Capture

Software version:

5.3, 6.2, 6.3

Operating system(s):

AIX, HP-UX, Linux, Solaris, Windows

Reference #:


Modified date:


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