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Diagnosing ORA-600 [2103] Issues in a NON RAC environment (Doc ID 406191.1)

Last updated on NOVEMBER 28, 2023

Applies to:

Oracle Database - Enterprise Edition - Version to [Release 8.1.7 to 18]
Oracle Database Cloud Schema Service - Version N/A and later
Oracle Database Exadata Cloud Machine - Version N/A and later
Oracle Cloud Infrastructure - Database Service - Version N/A and later
Oracle Database Backup Service - Version N/A and later
Information in this document applies to any platform.


This document explains how to troubleshoot and find out the cause of ORA-600 [2103] in a non RAC environment.

An ORA-600 [2103] is signaled when an Oracle process cannot get a CF(Control File) enqueue for 900 seconds.

The ORA-600 [2103] could be caused by:

  • Very slow I/O subsystem where the Control files are stored.
  • Frequent log switching - redo logs too small or insufficient logs
  • Async I/O issue or multiple db_writers, you can't use both of them, back one out
  • OS / Hardware issues

Note also that AIX 5.2 ML04 was causing frequent ORA-600[2103] and the error was fixed by upgrading the system to AIX 5.2 ML 05.

Troubleshooting Steps

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In this Document
Troubleshooting Steps

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