8 Removing Oracle Software

This chapter describes how to completely remove all Oracle Databases, their instances, and related software from an Oracle home directory. It includes information about the following topics:

Section 8.1, "Identifying All Instances"
Section 8.2, "Removing an Oracle Database"
Section 8.3, "Reconfiguring Oracle Cluster Synchronization Services"
Section 8.4, "Removing Oracle Software"

Note:

If you want to remove an Oracle Real Application Clusters (RAC) installation, then refer to Oracle Real Application Clusters Installation and Configuration Guide (B10766-08) for more information.

If you want to remove an individual product, then check the product-specific documentation for requirements and restrictions.

8.1 Identifying All Instances

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

$ type sys$login:[hostname]oratab

8.2 Removing an Oracle Database

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

Caution - Potential Loss of Data:

Removing an Oracle Database deletes all of the data in the database. If you want to keep this data, then ensure that you back up the database before deleting it.

Log in as the oracle user.
Enter the following command to change the directory to the default database location:
```
set default Oracle_home
```
At the prompt, specify the SID for the database that you want to remove:
```
$ @orauser sid
```
Start the Database Configuration Assistant (DBCA) by using the following command:
```
$ @dbca
```
The Welcome screen is displayed.
Click Next.

The Operations screen is displayed.
Select Delete a Database, then click Next.
Select the database that you want to delete, and then click Finish.
In the screen that is displayed, confirm that you want to delete the database.
When DBCA removes the database, you are prompted to select whether you want to perform another operation. Click Yes to return to the Operations screen or click No to exit from DBCA. If you want to remove another database, click Yes and repeat Steps 6 through 8.

8.3 Reconfiguring Oracle Cluster Synchronization Services

On cluster systems with Oracle Real Application Clusters (RAC) installations, the Cluster Synchronization Services (CSS) daemon is configured during the Oracle Cluster Ready Services (CRS) installation. If the system is running Oracle Cluster Ready Services (CRS), then refer to Oracle Real Application Clusters Installation and Configuration Guide (B10766-08) for information about removing RAC or CRS.

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, then 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 if other Oracle Database 10g installations exist on the system, then you must reconfigure the CSS daemon to run from another Oracle Database 10g Oracle home.

The following subsections describe how to complete these tasks:

Section 8.3.1, "Identifying Oracle Database 10g Oracle Homes"
Section 8.3.2, "Reconfiguring the Oracle CSS Daemon"
Section 8.3.3, "Deleting the Oracle CSS Daemon Configuration"

8.3.1 Identifying Oracle Database 10g Oracle Homes

Search the oratab file by using the following command:

$ type oratab

From the output, identify any Oracle home directories where Oracle Database 10g is installed. Oracle homes that contain Oracle Database 10g typically have paths similar to the following. However, they may use different paths.

/disk/oracle/db1010

If there is only one Oracle home directory that contains Oracle Database 10g, refer to Section 8.3.3, "Deleting the Oracle CSS Daemon Configuration" for information about deleting the Oracle CSS daemon configuration.

If you identify more than one Oracle Database 10g Oracle home directory, refer to the following section for information about reconfiguring the Oracle CSS daemon.

8.3.2 Reconfiguring the Oracle CSS Daemon

To reconfigure the Oracle CSS daemon so that it runs from an Oracle home that you are not removing:

Enter the following command to identify the Oracle home directory being used to run the CSS daemon:

$ type DISK:[MYLOGIN.vmshost.oracle]ocr.loc

The output from this command is similar to the following:

$ type  DISK:[MYLOGIN.vmshost.oracle]ocr.loc
ocrconfig_loc= VMSDEVICE:[ANY_VMS_DIR]ocr.dat
local_only=FALSE

The ocrconfig_loc parameter specifies the location of the Oracle Cluster Registry (OCR) used by the CSS daemon. The path is the Oracle home directory where the CSS daemon is running.

Note:

If the value for the local_only parameter is FALSE, Oracle CRS is installed on this system. Refer to Oracle Real Application Clusters Installation and Configuration Guide (B10766-08) for information about removing RAC or CRS.

If this Oracle home directory is not the Oracle home that you want to remove, you can continue to Section 8.4, "Removing Oracle Software".

Navigate to the Oracle home directory for an Oracle Database 10g installation that you are not removing.
Run the following command in this new Oracle home:
```
$ @orauser
```
Enter the following command to reconfigure the CSS daemon to run from this Oracle home:
```
$ @ora_root:[bin]localconfig "reset" ORACLE_HOME
```
The script stops the Oracle CSS daemon, reconfigures it in the new Oracle home, and then restarts it. When the system starts, the CSS daemon starts automatically from the new Oracle home.

8.3.3 Deleting the Oracle CSS Daemon Configuration

To delete the Oracle CSS daemon configuration:

Navigate to the Oracle home directory that you are removing.
Run the following command in the Oracle home:
```
$ @orauser
```
Enter the following command to delete the CSS daemon configuration from this Oracle home:
```
$ @ora_root:[bin]localconfig  delete
```
The script stops the Oracle CSS daemon, then deletes its configuration. When the system restarts, the CSS daemon does not start.

Note:

Delete the CSS daemon configuration only if you are certain that no other Oracle Database 10g installation requires it.

8.4 Removing Oracle Software

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

Remove any database instances that are associated with this Oracle home, and delete or reconfigure the Oracle CSS daemon.
Stop any processes running in this Oracle home:

Table 8-1 Commands to Stop Processes Running in Oracle Home

Process Name Command

Oracle Net Services listener lsnrctl stop
If necessary, log in as the oracle user.
Run the orauser.com file to redefine the Oracle home.
```
$ @orauser
```
Start Oracle Universal Installer as follows:
```
$ @ora_root:[oui.bin]runinstaller.com
```
In the Welcome screen, click Deinstall Products.

The Inventory screen is displayed, listing all of the Oracle homes on the system.
In the Inventory screen, select the Oracle home and the products that you want to remove, then click Remove.

Caution:
If you select to remove Oracle JVM, then Oracle Universal Installer removes all installed products that depend on Oracle JVM, including Oracle Database.
When Oracle Universal Installer displays a confirmation screen asking you to confirm that you want to uninstall the products and their dependent components, click Yes.

The Installer displays a progress indicator as it removes the software.
When the products have been deleted, click Cancel to exit from Oracle Universal Installer, then click Yes.

Process Name	Command
Oracle Net Services listener	`lsnrctl stop`

Note:

Always use Oracle Universal Installer to remove Oracle software. Do not delete any Oracle home directories without first using Oracle Universal Installer to remove the software.