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Primary Note: Overview of Database Startup and Shutdown (Doc ID 1505155.1)

Last updated on JANUARY 30, 2022

Applies to:

Gen 1 Exadata Cloud at Customer (Oracle Exadata Database Cloud Machine) - Version N/A and later
Oracle Cloud Infrastructure - Database Service - Version N/A and later
Oracle Database Cloud Exadata Service - Version N/A and later
Oracle Database Exadata Express Cloud Service - Version N/A and later
Oracle Database Cloud Service - Version N/A and later
Information in this document applies to any platform.


This document provides an overview of the database startup and shutdown, including the various phases and steps. This is not intended to be a troubleshooting document. But provides a clear understanding on how the the single instance database startup and shutdown works. If you need assistance in troubleshooting please Refer :
Note 851057.1 - Troubleshooting Database Startup/Shutdown Problems




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In this Document
 Oracle Database and Instance
 Database Startup
 Nomount Stage
 Mount Stage 
 Open Stage
 Instance recovery:
 Database Shutdown
 Different Modes in Database Shutdown
 Shutdown Immediate
 Shutdown Transactional
 Shutdown Normal
 Shutdown Abort
 Different Phases in Database Shutdown
 Close the Database
 Dismount the Database
 Shutdown the Instance
 Steps for a Clean Startup after an Instance Crash
 Issues Encountered During Startup and Shutdown

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