6 Removing Oracle Software

6.1 Overview

To completely remove all Oracle databases, instances, and software from an Oracle home directory, you must:

• Identify all instances associated with the Oracle home.

• Remove database and Automatic Storage Management instances.

• Shut down processes.

• Reconfigure the Oracle Cluster Synchronization Services Daemon, if necessary.

• Remove the Oracle software.

6.2 Identifying All Instances

To identify all instances associated with the Oracle home that you want to remove, enter the following command:

$ more /etc/oratab

The output of this command contains entries similar to the following:

+ASM:/u01/app/oracle/product/10.2.0/db_1:N
CUST:/u01/app/oracle/product/10.2.0/db_1:N

These entries show that the +ASM Automatic Storage Manager instance and the CUST Oracle database instance are associated with the /u01/app/oracle/product/10.2.0/db_1 Oracle home directory.

6.3 Removing an Oracle Database

To completely remove Oracle Database software, you must remove any installed databases. To remove an Oracle database:

1. Log in as the oracle user:

   $ su - oracle
   

2. Run the oraenv or coraenv script to set the environment for the database that you want to remove, for example:

   • Bourne, Bash, or Korn shell:

     $ . /usr/local/bin/oraenv
     

   • C shell:

     % source /usr/local/bin/coraenv
     

3. At the prompt, specify the SID for the database that you want to remove.

4. Start the Database Configuration Assistant:

   $ dbca
   

   The Welcome window appears.

5. Click Next.

   The Operations window appears.

6. Select Delete a Database, then click Next.

7. Select the database that you want to delete, then click Finish.

8. In the window that appears, confirm that you want to delete the database.

9. When Database Configuration Assistant removes the database, you are prompted to choose whether you want to perform another operation. Click Yes to return to the Operations screen or click No to exit from Database Configuration Assistant. If you want to remove another database, click Yes and repeat steps 6 through 8.

6.4 Removing an Automatic Storage Management Instance

To completely remove Oracle database software, you must also remove any Automatic Storage Management instances running in the Oracle home. To remove an Automatic Storage Management instance:

1. If necessary, log in as the oracle user:

   $ su - oracle
   

2. Run the oraenv or coraenv script to set the environment for the Automatic Storage Management instance that you want to remove, for example:

   • Bourne, Bash, or Korn shell:

     $ . /usr/local/bin/oraenv
     

   • C shell:

     $ source /usr/local/bin/coraenv
     

3. At the prompt, specify the SID for the Automatic Storage Management instance that you want to remove.

4. Connect to the Automatic Storage Management instance as the SYS user:

   $ sqlplus "SYS/SYS_PASSWORD AS SYSDBA"
   

5. Enter the following command to determine whether any Oracle database instance is using the Automatic Storage Management instance:

   SQL> SELECT INSTANCE_NAME FROM V$ASM_CLIENT;
   

   This command lists all of the database instances that are using this Automatic Storage Management instance.

   Note:

   This command only lists database instances that are running. It is possible that other instances are associated with the Automatic Storage Management instance, but they are not currently running.

   If you removed a database from this Oracle home but the output from the command shows that this Automatic Storage Management instance is supporting a database instance in another Oracle home, do not remove the Automatic Storage Management instance or the Oracle home.

6. If there are no database instances associated with this Automatic Storage Management instance, drop the disk groups associated with this instance as follows:

   Note:

   Dropping the Automatic Storage Management disk group makes the disk device available for use with another Automatic Storage Management instance if required. However, all data in the disk group is lost. Make sure that no other database instance requires any data from this disk group before you drop it.

   1. Identify the disk groups associated with the Automatic Storage Management instance:

      SQL> SELECT NAME FROM V$ASM_DISKGROUP;
      

   2. For each disk group that you want to delete, enter a command similar to the following:

      SQL> DROP DISKGROUP name INCLUDING CONTENTS;
      

7. Enter the following command to shut down the Automatic Storage Management instance:

   SQL> SHUTDOWN
   

8. Remove the entry for the Automatic Storage Management instance from the /etc/oratab file.

6.5 Reconfiguring Oracle Cluster Synchronization Services

Oracle Cluster Synchronization Services (CSS) is a daemon process that is configured by the root.sh script when you configure an Automatic Storage Management instance. It is configured to start every time the system boots. This daemon process is required to enable synchronization between Oracle Automatic Storage Management and database instances. It must be running if an Oracle database is using Automatic Storage Management for database file storage.

Before you remove an Oracle Database 10g Oracle home, you must determine whether the CSS daemon is running from that Oracle home and whether any other Oracle Database 10g Oracle homes exist on the system:

• If the Oracle Database 10g Oracle home that you want to remove is the only Oracle Database 10g installation on the system, you can delete the CSS daemon configuration.

• If the CSS daemon is running from the Oracle Database 10g Oracle home that you want to remove and other Oracle Database 10g installations exist on the system, you must reconfigure the CSS daemon to run from another Oracle Database 10g Oracle home.

The following sections describe how to complete these tasks:

• Identifying Oracle Database 10g Oracle Homes

• Reconfiguring the Oracle CSS Daemon

• Deleting the Oracle CSS Daemon Configuration

$ more /etc/oratab

/mount_point/app/oracle/product/10.2.0/db_n

6.6 Removing Oracle Software

The following steps describe how to use Oracle Universal Installer to remove Oracle software from an Oracle home:

1. If necessary, log in as the oracle user:

   $ su - oracle
   

2. Set the ORACLE_HOME environment variable to specify the path of the Oracle home directory that you want to remove:

   • Bourne, Bash, or Korn shell:

     $ ORACLE_HOME=/u01/app/oracle/product/10.2.0/db_1 
     $ export ORACLE_HOME
     

   • C shell:

     $ setenv ORACLE_HOME /u01/app/oracle/product/10.2.0/db_1
     

3. Remove any databases or Automatic Storage Management instances associated with this Oracle home and delete or reconfigure the Oracle CSS daemon.

   Refer to the preceding sections for information about how to complete these tasks.

4. Stop any processes running in this Oracle home:

   Process Name	Command
   Database Control	$ORACLE_HOME/bin/emctl stop dbconsole
   Oracle Net listener	$ORACLE_HOME/bin/lsnrctl stop
   iSQL*Plus	$ORACLE_HOME/bin/isqlplusctl stop
   Ultra Search	$ORACLE_HOME/bin/searchctl stop

   
   

5. Start Oracle Universal Installer as follows:

   $ $ORACLE_HOME/oui/bin/runInstaller
   

6. In the Welcome window, click Deinstall Products.

   The Inventory screen appears, listing all of the Oracle homes on the system.

7. In the Inventory screen, select the Oracle home and the products that you want to remove, then click Remove.

   Note:

   If you choose to remove Oracle JVM, Oracle Universal Installer removes all installed products that depend on Oracle JVM, including Oracle Database 10g.

   Oracle Universal Installer displays a confirmation window asking you to confirm that you want to deinstall the products and their dependent components.

8. Click Yes.

   Oracle Universal Installer displays a progress indicator as it removes the software.

9. Click Close on the Inventory screen.

10. When the products have been deleted, click Cancel to exit from Oracle Universal Installer, and then click Yes.