ORA-00600: Internal Oracle Error Code – Complete Oracle DBA Troubleshooting Guide

The ORA-00600: internal Oracle error code is one of the most serious Oracle Database errors that a Database Administrator (DBA) can encounter. Unlike common Oracle errors such as ORA-01017 or ORA-12541, ORA-00600 does not point to a specific user or configuration issue. Instead, it indicates that the Oracle database kernel has detected an unexpected internal condition while executing a database operation.

An ORA-00600 error may occur during SQL execution, PL/SQL processing, database startup, RMAN backup, media recovery, Data Guard redo apply, Oracle RAC operations, or routine background processes. The underlying cause can range from Oracle software bugs and corrupted data blocks to memory corruption, storage issues, operating system problems, or hardware failures.

Because ORA-00600 originates from Oracle's internal code, simply restarting the database rarely resolves the problem permanently. Successful troubleshooting requires careful analysis of the Oracle Alert Log, trace files, incident diagnostics, Automatic Diagnostic Repository (ADR), and the ORA-00600 arguments recorded with the error.

This comprehensive guide explains the Oracle internal architecture behind ORA-00600, how to interpret the error arguments, production-tested troubleshooting techniques, Oracle RAC and Data Guard considerations, Oracle Cloud Infrastructure (OCI) recommendations, diagnostic commands, and Oracle DBA best practices for Oracle Database 11g, 12c, 18c, 19c, 21c, and Oracle Database 23ai.

Quick Solution

Do not restart the database immediately. Review the Oracle Alert Log, identify the ORA-00600 arguments, analyze the associated trace files, collect ADR diagnostics, determine whether the issue is caused by an Oracle bug, corruption, or infrastructure problem, and apply the appropriate Oracle patch or corrective action.

Error Message

ORA-00600: internal error code, arguments:
[ktsircinfo_num1], [7], [1024], [1921]

Every ORA-00600 error contains one or more arguments. These arguments are essential because they identify the internal Oracle function or assertion that detected the unexpected condition.

Understanding the ORA-00600 Arguments

The first argument is the most important part of the error message because it identifies the Oracle kernel component that raised the exception.

Argument	Description
First Argument	Internal Oracle function or assertion name (for example, `ktsircinfo_num1`).
Second Argument	Internal diagnostic value.
Third Argument	Additional memory or object information.
Remaining Arguments	Oracle diagnostic values used during root cause analysis.

When opening an Oracle Support Service Request (SR), always include the complete ORA-00600 message and every argument exactly as recorded in the Alert Log or trace file.

What is ORA-00600?

ORA-00600 is a generic internal Oracle Database error raised whenever the Oracle kernel detects an unexpected condition that should never normally occur during database processing.

Unlike user-generated Oracle errors, ORA-00600 is generated by Oracle's internal source code after a built-in consistency check or assertion fails.

Common situations where ORA-00600 may occur include:

SQL execution
PL/SQL execution
Database startup
RMAN backup or restore
Media recovery
Oracle RAC cluster activity
Data Guard redo apply
Automatic background processes

Although many ORA-00600 errors are caused by Oracle software defects, they can also be triggered by corrupted blocks, storage failures, operating system issues, memory corruption, or unexpected hardware events.

Oracle Internal Error Architecture

Oracle Database consists of multiple internal kernel components that work together to process SQL statements, manage memory, maintain transactions, and perform recovery.

               Oracle Database

                     │

     +-------------------------------+

     |       Oracle Kernel           |

     +-------------------------------+

        │        │         │

        │        │         │

 Memory   Storage   SQL Execution

 Manager  Manager    Engine

        │

        ▼

 Internal Assertions

        │

 Unexpected Condition

        │

        ▼

      ORA-00600

Whenever one of these internal components detects an unexpected state, Oracle generates ORA-00600 to prevent further corruption or inconsistent processing.

Common Causes of ORA-00600

1. Oracle Software Bugs

Many ORA-00600 errors are associated with known Oracle software defects that have already been corrected in Release Updates (RUs) or one-off patches.

2. Corrupted Data Blocks

Physical or logical corruption within database blocks may trigger internal consistency checks, resulting in ORA-00600 during SQL execution or recovery.

3. Memory Corruption

Incorrect memory allocation, Shared Pool corruption, PGA corruption, or operating system memory issues can lead to internal Oracle exceptions.

4. Storage Problems

Disk failures, storage controller errors, filesystem corruption, SAN issues, or ASM disk problems may generate ORA-00600 during I/O operations.

5. Oracle Dictionary Corruption

Corruption affecting Oracle data dictionary objects may prevent normal database processing and generate internal errors.

6. Incomplete Recovery

Improper database recovery or interrupted recovery operations may leave Oracle metadata in an inconsistent state.

7. Oracle RAC Issues

Cluster synchronization failures, Global Cache problems, node evictions, or interconnect issues may occasionally result in ORA-00600.

8. Data Guard Problems

Redo Apply inconsistencies, archived log corruption, or standby synchronization failures may produce internal Oracle errors.

9. Operating System or Hardware Failures

Unexpected operating system behavior, defective memory modules, CPU faults, firmware issues, or storage hardware failures may trigger Oracle kernel assertions.

Common Symptoms

Database session terminates unexpectedly.
Background process crashes.
Instance termination.
ORA-03113: End-of-file on communication channel.
ORA-07445: Exception encountered.
RMAN backup failures.
Media recovery interruption.
Database startup failures.
Unexpected Oracle process termination.

ORA-00600 Compared with Related Oracle Errors

Error	Description	Primary Area
ORA-00600	Internal Oracle kernel error.	Oracle Kernel
ORA-07445	Operating system exception.	OS / Oracle Process
ORA-03113	Communication channel terminated.	Client/Server Communication
ORA-04031	Unable to allocate shared memory.	Memory Management
ORA-27101	Shared Memory Realm Does Not Exist.	Database Startup
ORA-01034	ORACLE Not Available.	Database Availability

Production DBA Recommendation

Never assume ORA-00600 is simply an Oracle software bug. Before applying patches or restarting the database, identify the first ORA-00600 argument, review the Alert Log and trace files, verify storage and memory health, and determine whether the issue is caused by corruption, infrastructure, or a known Oracle defect. Accurate diagnosis significantly reduces downtime and prevents recurring failures.

Step-by-Step Oracle DBA Troubleshooting

Successfully resolving ORA-00600 requires identifying the root cause rather than simply clearing the symptom. Since ORA-00600 is generated by Oracle's internal kernel, every occurrence should be investigated carefully before restarting the database or applying patches.

The following troubleshooting workflow reflects production-tested Oracle DBA best practices.

Step 1 – Review the Oracle Alert Log

The Alert Log is the primary source of information whenever ORA-00600 occurs.

Typical Linux location:

$ORACLE_BASE/diag/rdbms/<database_name>/<instance_name>/trace/

alert_<SID>.log

Look for messages immediately preceding ORA-00600.

Pay special attention to:

ORA-07445
ORA-03113
ORA-04031
ORA-01578 Block Corruption
ORA-01110 Datafile Information
Operating system I/O errors
Background process termination

DBA Tip

The root cause usually appears before the ORA-00600 message. Always investigate earlier log entries rather than focusing only on the internal error itself.

Step 2 – Review the Incident Trace File

Every ORA-00600 generates one or more incident trace files within the Automatic Diagnostic Repository (ADR).

Navigate to:

$ORACLE_BASE/diag/rdbms/

<database_name>/

<instance_name>/trace/

The trace file normally contains:

Complete ORA-00600 arguments
Call stack
Error stack
Current SQL statement
Process information
Memory dump
Incident details

Step 3 – Use ADRCI

Oracle's Automatic Diagnostic Repository Command Interpreter (ADRCI) simplifies incident management.

Start ADRCI:

adrci

Display recent incidents:

SHOW INCIDENT;

Display recent problems:

SHOW PROBLEM;

Review the generated incident number for the ORA-00600 event.

Step 4 – Create an IPS Diagnostic Package

Before opening a Service Request with Oracle Support, create an Incident Packaging Service (IPS) package.

IPS CREATE PACKAGE
PROBLEM 1;

Then generate the package.

IPS GENERATE PACKAGE 1
IN '/tmp';

The IPS package includes:

Alert Log
Trace files
Incident metadata
Health Monitor results
Diagnostic information

Step 5 – Identify the First ORA-00600 Argument

The first argument identifies the Oracle internal assertion.

Example:

ORA-00600:

[ktsircinfo_num1]

[7]

[1024]

[1921]

This first value helps Oracle Support identify whether the issue is:

Known Oracle Bug
Memory corruption
Dictionary corruption
Storage problem
Recovery inconsistency

Step 6 – Identify Recent Database Changes

Ask the following questions:

Was a Release Update recently applied?
Was database recovery performed?
Were initialization parameters changed?
Was storage migrated?
Were database objects rebuilt?
Was the operating system updated?

Many ORA-00600 incidents occur shortly after environmental changes.

Step 7 – Check Database Health

Verify instance status.

SELECT

INSTANCE_NAME,

STATUS

FROM V$INSTANCE;

Check database status.

SELECT

NAME,

OPEN_MODE

FROM V$DATABASE;

Confirm background processes are operating normally.

Step 8 – Check for Block Corruption

ORA-00600 is sometimes triggered by corrupted database blocks.

Identify corruption.

SELECT *

FROM V$DATABASE_BLOCK_CORRUPTION;

If corruption exists, determine whether RMAN recovery or block media recovery is required.

Step 9 – Review AWR Report

Generate an AWR report covering the time immediately before ORA-00600 occurred.

Review:

Top Wait Events
Top SQL
Memory Advisors
CPU Usage
I/O Statistics
Latch Activity
Library Cache

Step 10 – Review ASH Report

ASH helps identify what the affected sessions were doing immediately before the internal error.

Focus on:

Current SQL
Blocking sessions
Wait Events
CPU usage
Session history

Step 11 – Oracle RAC Considerations

For Oracle RAC databases:

Determine whether one node or multiple nodes experienced ORA-00600.
Check Clusterware resources.
Review node eviction history.
Verify interconnect stability.
Review Global Cache activity.

Useful commands:

srvctl status database

crsctl stat res -t

Step 12 – Oracle Data Guard Considerations

ORA-00600 may occur during Redo Apply or Managed Recovery.

Review:

MRP status
Archive Log shipping
Standby Alert Log
Redo Apply lag
Broker status

Step 13 – Oracle Cloud Infrastructure (OCI)

For databases hosted on OCI:

Verify Compute Instance health.
Review Block Volume performance.
Check operating system memory.
Review OCI monitoring metrics.
Verify Autonomous Health Framework (AHF) diagnostics.

Step 14 – Verify Oracle Software Version

Many ORA-00600 incidents are resolved through Oracle Release Updates.

Check the database version.

SELECT

BANNER_FULL

FROM V$VERSION;

Also determine whether the reported first argument corresponds to a documented Oracle bug addressed in a later Release Update.

Real Production Case Study

A financial institution reported intermittent ORA-00600 errors after upgrading to a newer Oracle Release Update. Database sessions terminated unexpectedly, and several overnight batch jobs failed.

The DBA reviewed the Alert Log and identified a recurring ORA-00600 with the same first argument. Using ADRCI, the incident trace files and IPS package were collected and submitted to Oracle Support.

Oracle confirmed the issue was a known software defect corrected in a newer Release Update. After applying the recommended patch and validating the database, the ORA-00600 errors were completely eliminated.

Oracle DBA Troubleshooting Checklist

Verification	Status
Alert Log Reviewed	☐
Trace File Reviewed	☐
First ORA-00600 Argument Identified	☐
Incident Package Created	☐
Database Health Verified	☐
Corruption Checked	☐
AWR Reviewed	☐
ASH Reviewed	☐
RAC / Data Guard Reviewed	☐
Oracle Version Verified	☐
Root Cause Identified	☐
Patch or Corrective Action Applied	☐

Oracle Version Considerations

ORA-00600 exists across all supported Oracle Database releases, but diagnostic capabilities have improved significantly over time.

Oracle Version	Diagnostic Highlights
Oracle 10g	Basic trace diagnostics and manual log analysis.
Oracle 11g	Introduction of ADR, incident management, and IPS packaging.
Oracle 12c	Enhanced Multitenant diagnostics and Health Monitor integration.
Oracle 18c / 19c	Improved AWR, ASH, and incident packaging stability.
Oracle 21c / 23ai	Enhanced cloud diagnostics, AHF integration, and OCI monitoring support.

Oracle Support Workflow

When ORA-00600 occurs in production, Oracle Support expects a complete diagnostic package. Prepare the following before opening a Service Request (SR):

Alert Log
Incident trace files
Complete ORA-00600 arguments
Database version and Release Update level
AWR report covering the failure period
ASH report (if licensed)
IPS package generated with ADRCI
Recent configuration or patch changes

Providing complete diagnostics significantly reduces troubleshooting time.

Common Mistakes

Restarting the database before collecting diagnostics.
Ignoring the first ORA-00600 argument.
Deleting trace files prematurely.
Applying patches without confirming the root cause.
Assuming every ORA-00600 is an Oracle bug.
Ignoring storage and operating system health.
Failing to create an IPS package before opening an SR.
Ignoring recurring incidents with the same first argument.
Not checking for corruption when ORA-01578 is present.
Overlooking recent infrastructure changes.

Oracle DBA Best Practices

Keep Oracle Release Updates current.
Enable proactive monitoring for Alert Log errors.
Maintain regular RMAN backups and validation checks.
Monitor storage latency and I/O errors.
Review operating system logs regularly.
Test recovery procedures periodically.
Document all database and infrastructure changes.
Retain ADR diagnostic history for production systems.
Monitor memory and filesystem health continuously.
Automate incident collection where possible.

Useful Diagnostic Commands

Command	Purpose
`adrci`	Open ADR command interpreter.
`SHOW INCIDENT`	List recent incidents.
`SHOW PROBLEM`	List diagnostic problems.
`SHOW ALERT`	Display Alert Log entries.
`ips create package problem n`	Create IPS package.
`ips generate package n in '/tmp'`	Generate IPS package file.
`srvctl status database`	Check RAC database status.
`crsctl stat res -t`	Display Clusterware resources.
`tail -100 alert.log`	Review recent Alert Log entries.

Useful SQL Queries

Check Database Status

SELECT INSTANCE_NAME, STATUS FROM V$INSTANCE;

Check Database Open Mode

SELECT NAME, OPEN_MODE FROM V$DATABASE;

Check Corruption

SELECT * FROM V$DATABASE_BLOCK_CORRUPTION;

Check Current SQL for Active Sessions

SELECT SID, SERIAL#, SQL_ID, EVENT
FROM V$SESSION
WHERE STATUS='ACTIVE';

Check Oracle Version

SELECT BANNER_FULL FROM V$VERSION;

ORA-00600 Troubleshooting Flowchart

ORA-00600

      │

      ▼

Review Alert Log

      │

      ▼

Review Trace File

      │

      ▼

Identify First Argument

      │

      ▼

Check Recent Changes

      │

      ▼

Check Corruption

      │

      ▼

Review AWR / ASH

      │

      ▼

Generate IPS Package

      │

      ▼

Determine Root Cause

      │

      ▼

Apply Patch / Recovery / Fix

      │

      ▼

Validate Database Stability

Frequently Asked Questions (FAQ)

Is ORA-00600 always an Oracle bug?

No. Many ORA-00600 errors are caused by corruption, storage failures, memory problems, operating system issues, or hardware faults.

Should I restart the database immediately?

No. Always collect diagnostics before restarting the instance. Restarting may remove valuable evidence required for root cause analysis.

What is the most important ORA-00600 argument?

The first argument is the most important because it identifies the Oracle internal assertion that detected the error.

Can ORA-00600 occur during RMAN backup?

Yes. Internal errors may occur during backup, restore, validation, or recovery operations.

Can hardware problems cause ORA-00600?

Yes. Faulty memory, storage controllers, disks, firmware, or other hardware components can trigger Oracle internal errors.

What information should I provide to Oracle Support?

Provide the Alert Log, trace files, complete ORA-00600 arguments, IPS package, Oracle version, AWR report, and details of recent changes.

About the Author

Rana Abdul Wahid is an Oracle Database Consultant with more than 15 years of experience in Oracle Database Administration, Oracle RAC, Oracle Data Guard, RMAN Backup & Recovery, Oracle E-Business Suite, Oracle Cloud Infrastructure (OCI), Performance Tuning, Linux/Unix Administration, MySQL, Microsoft SQL Server, PostgreSQL, and enterprise database management.

Through this blog, he shares production-tested Oracle DBA solutions, real-world troubleshooting guides, backup and recovery strategies, Oracle performance tuning techniques, and enterprise best practices to help database professionals solve complex Oracle issues with confidence.

Learn more about the author →

Conclusion

The ORA-00600: Internal Oracle Error Code is a critical Oracle kernel error that requires careful investigation rather than immediate restart actions. The most important diagnostic clue is the first ORA-00600 argument, which identifies the internal Oracle component that detected the unexpected condition.

A disciplined troubleshooting process—reviewing the Alert Log, analyzing trace files, using ADRCI and IPS diagnostics, checking for corruption, reviewing AWR and ASH reports, and verifying infrastructure health—allows Oracle DBAs to determine the true root cause and apply an effective corrective action.

By maintaining current Oracle patches, monitoring database health proactively, validating backups regularly, and following the production-tested best practices described in this guide, DBAs can significantly reduce the impact of ORA-00600 incidents and improve the stability of mission-critical Oracle databases.

Final DBA Recommendation

Treat every ORA-00600 occurrence as a potentially serious database event. Collect diagnostics before restarting services, preserve all trace files, identify the first argument, and determine whether the issue is caused by Oracle software, corruption, storage, memory, or infrastructure. Accurate root cause analysis is the key to preventing recurrence and protecting database integrity.

Found this guide helpful? Explore our Oracle Error Codes Guide for more production-tested Oracle DBA tutorials, troubleshooting guides, and performance optimization techniques.

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