Cloning Database Using Enterprise Manager
It is possible to clone the database directly from Oracle
Enterprise Manager (OEM). By
using the OEM cloning feature, this makes it possible to clone the
database with some simple mouse clicks without running any RMAN
script. Take a backup of the database to the same host using
Open OEM and switch to the Maintenance tab and in the Data
Movement section, select the Clone Database link:
Figure 5.1: Selection in the Maintenance Tab
As a source type, select A running database instance? and click
Figure 5.2: Choice in Clone Database for Source Type
In this step, provide the location for the working directory. The
backup of the database will be stored in this directory. If the
working directory needs to be deleted after the clone operation,
select the first option. Below that, enter the username and
password of the user who owns the Oracle software and click Next.
Figure 5.3: Clone Database: Source Working Directory Screen
In next screen, enter the name of the new clone database and click
Figure 5.4: Clone Database: Select Destination Screen
Now provide the destination for the database files of the clone
database. If a different directory needs to be given, then click
the Customize button. Next, select the network configuration file
location and provide passwords for specific users.
Figure 5.5: Clone Database: Destination Options Screen
By clicking the Customize button, a different directory for every
file of the database will be able to be provided as follows:
Figure 5.6: Customize Destination Options Screen
Here, Oracle schedules a job to clone the database. This job can
be run immediately or be made to run anytime that is desired. Just
click Next to make it run immediately.
Figure 5.7: Clone Database: Schedule
This is the last page of configuring the clone of the database.
Just click the Submit Job button and the clone processwill begin:
Figure 5.8: Reviewing the Clone Database Process
Here, a message that cloning has been started will appear:
Figure 5.9: Clone Database Confirmation Message
The status of the clone operation can be viewed by clicking on the
View Status button:
Figure 5.10: Viewing the Status of the Clone Operation
Click on the name of the job to get more information about the
Figure 5.11: Job Information Screen
Click on the status of the job:
Figure 5.12: Summary Status of the Job
As can be seen, the clone operation has started and this shows
that the steps that were performed were successful. Now press F5
to refresh the pages and see that the steps are performing
automatically. At last, the final summary will appear and the
cloning process ends.
Figure 5.13: Final Summary of the Clone Process
Now connect to the db2 database and check the status of the
instance to be sure that it was cloned successfully.
$ export ORACLE_SID=db2
$ sqlplus "/ as sysdba"
It can now be seen that the production database was
Pre & Post Cloning Changes
To avoid the confusion between the
production and test/development databases, do not set the clone
database name as a production database name.
It is not mandatory to have the
initialization parameter's value of the cloned instancesimilar to the production instance. Of course, the
source, i.e. the production database, must be in archivelog mode
for the duration of the cloning.
It is not compulsory to have the
cloned instance in archivelog mode because unnecessary
archivelog files are generated which consume hard disk space.
If the cloned instance crashes and
needs to be recovered, it can easily be cloned again from the
After the clone, change the system
users' passwords, i.e. SYS and SYSTEM, and any critical and
application users' passwords.
Disable the jobs which are not
required to be run in the cloned instance.
Change any application users' tables
from the cloned database that are still referring the production
database, i.e. server IP, port details, printer details and