Deinstalling Oracle DB 12c software

There are some situations that demands us to uninstall the installed software. same thing happen for me today I was trying to install the Oracle Database 12c in silent mode the logs tells that there is some prerequisites not matched. Hence the installation log retured with non zero value that is 6.

To re-install my software I need to uninstall the existing software.

To uninstall Oracle Database navigate to the ORACLE_HOME then find deinstall directory containing the deinstall command.

$cd /u01/app/oracle/product/12.1.0.2/dbhome_1/deinstall
./deinstall
Checking for required files and bootstrapping ...
Please wait ...
Location of logs /tmp/deinstall2016-04-25_04-18-49AM/logs/

############ ORACLE DECONFIG TOOL START ############

The product version number of the specified home cannot be determined. Is the product version 12.1.0.2.0 (y - yes, n - no)? [n]y

######################### DECONFIG CHECK OPERATION START #########################
## [START] Install check configuration ##
The deinstall tool cannot determine the home type needed to deconfigure the selected home.  Please select the type of Oracle home you are trying to deinstall.
Single Instance database - Enter 1
Real Application Cluster database - Enter 2
Grid Infrastructure for a cluster - Enter 3
Grid Infrastructure for a stand-alone server - Enter 4
Client Oracle Home - Enter 5
Transparent Gateways Oracle Home - Enter 6
GSM Oracle Home - Enter 7
1
The product version number of the specified home cannot be determined. Is the product version at least 11.2.0.1.0 (y - yes, n - no)? [n]
y


Checking for existence of the Oracle home location /u01/app/oracle/product/12.1.0.2/dbhome_1
Oracle Home type selected for deinstall is: Oracle Single Instance Database
Oracle Base selected for deinstall is:
Checking for existence of central inventory location /oracle/oraInventory

## [END] Install check configuration ##


Network Configuration check config START

Network de-configuration trace file location: /tmp/deinstall2016-04-25_04-18-49AM/logs/netdc_check2016-04-25_04-23-44-AM.log

Network Configuration check config END

Database Check Configuration START

Database de-configuration trace file location: /tmp/deinstall2016-04-25_04-18-49AM/logs/databasedc_check2016-04-25_04-23-48-AM.log

Use comma as separator when specifying list of values as input

Specify the list of database names that are configured in this Oracle home []:
Database Check Configuration END
Oracle Configuration Manager check START
OCM check log file location : /tmp/deinstall2016-04-25_04-18-49AM/logs//ocm_check7593.log
Oracle Configuration Manager check END

######################### DECONFIG CHECK OPERATION END #########################


####################### DECONFIG CHECK OPERATION SUMMARY #######################
Oracle Home selected for deinstall is: /u01/app/oracle/product/12.1.0.2/dbhome_1
Inventory Location where the Oracle home registered is: /gbuora/oraInventory
Checking the config status for CCR
Oracle Home exists with CCR directory, but CCR is not configured
CCR check is finished
Do you want to continue (y - yes, n - no)? [n]: y
A log of this session will be written to: '/tmp/deinstall2016-04-25_04-18-49AM/logs/deinstall_deconfig2016-04-25_04-19-43-AM.out'
Any error messages from this session will be written to: '/tmp/deinstall2016-04-25_04-18-49AM/logs/deinstall_deconfig2016-04-25_04-19-43-AM.err'

######################## DECONFIG CLEAN OPERATION START ########################
Database de-configuration trace file location: /tmp/deinstall2016-04-25_04-18-49AM/logs/databasedc_clean2016-04-25_04-24-15-AM.log

Network Configuration clean config START

Network de-configuration trace file location: /tmp/deinstall2016-04-25_04-18-49AM/logs/netdc_clean2016-04-25_04-24-15-AM.log

De-configuring backup files...
Backup files de-configured successfully.

The network configuration has been cleaned up successfully.

Network Configuration clean config END

Oracle Configuration Manager clean START
OCM clean log file location : /tmp/deinstall2016-04-25_04-18-49AM/logs//ocm_clean7593.log
Oracle Configuration Manager clean END

######################### DECONFIG CLEAN OPERATION END #########################


####################### DECONFIG CLEAN OPERATION SUMMARY #######################
Cleaning the config for CCR
As CCR is not configured, so skipping the cleaning of CCR configuration
CCR clean is finished
#######################################################################


############# ORACLE DECONFIG TOOL END #############

Using properties file /tmp/deinstall2016-04-25_04-18-49AM/response/deinstall_2016-04-25_04-19-43-AM.rsp
Location of logs /tmp/deinstall2016-04-25_04-18-49AM/logs/

############ ORACLE DEINSTALL TOOL START ############





####################### DEINSTALL CHECK OPERATION SUMMARY #######################
A log of this session will be written to: '/tmp/deinstall2016-04-25_04-18-49AM/logs/deinstall_deconfig2016-04-25_04-19-43-AM.out'
Any error messages from this session will be written to: '/tmp/deinstall2016-04-25_04-18-49AM/logs/deinstall_deconfig2016-04-25_04-19-43-AM.err'

######################## DEINSTALL CLEAN OPERATION START ########################
## [START] Preparing for Deinstall ##
Setting LOCAL_NODE to localhost
Setting CRS_HOME to false
Setting oracle.installer.invPtrLoc to /tmp/deinstall2016-04-25_04-18-49AM/oraInst.loc
Setting oracle.installer.local to false

## [END] Preparing for Deinstall ##

Setting the force flag to false
Setting the force flag to cleanup the Oracle Base
Oracle Universal Installer clean START

Detach Oracle home '/u01/app/oracle/product/12.1.0.2/dbhome_1' from the central inventory on the local node : Done

Delete directory '/u01/app/oracle/product/12.1.0.2/dbhome_1' on the local node : Done

Delete directory '/gbuora/oraInventory' on the local node : Done

Oracle Universal Installer cleanup was successful.

Oracle Universal Installer clean END


## [START] Oracle install clean ##

Clean install operation removing temporary directory '/tmp/deinstall2016-04-25_04-18-49AM' on node 'localhost'

## [END] Oracle install clean ##


######################### DEINSTALL CLEAN OPERATION END #########################


####################### DEINSTALL CLEAN OPERATION SUMMARY #######################
Successfully detached Oracle home '/u01/app/oracle/product/12.1.0.2/dbhome_1' from the central inventory on the local node.
Successfully deleted directory '/u01/app/oracle/product/12.1.0.2/dbhome_1' on the local node.
Successfully deleted directory '/gbuora/oraInventory' on the local node.
Oracle Universal Installer cleanup was successful.

Run 'rm -r /opt/ORCLfmap' as root on node(s) 'localhost' at the end of the session.
Run 'rm -r /etc/oratab' as root on node(s) 'localhost' at the end of the session.
Oracle deinstall tool successfully cleaned up temporary directories.
#######################################################################


############# ORACLE DEINSTALL TOOL END #############

Then you will be no longer having the directory structure which was used for Oracle Database.

Reference document:

Remov Oracle Database Software