SAMEER WADHWA

Sr. Oracle DBA

10 steps for cloning a database.

Summary :-

                        The following steps must be on Source -Production instance/Server

Step 1. Shutdown database in normal mode and start it up in restricted mode.

Step 2. Take the backup of control file

Step 3. Shutdown database again in normal mode.

Step 4. Copy /FTP init parameter file ,control file script and all the database file on the destination server/location, once all the files are successfully copied, you may startup the database normally.

The following step must be on destination – Clone instance/server

Step 5. Edit init parameter file and control file script.

Step 6. New Environment setup .

Step 7. Connect with svrmgrl and recreate control file

Step 8. Open the database in resetlogs.

Step 9. Shutdown the database in normal mode

Step 10. Take the cold backup and start the database in archive/non archive mode.

Details :-

Step 1 – 3 on the Source Server ( Server A)

SVRMGR> connect internal/oracle

Connected.

SVRMGR> shutdown ;

Database closed.

Database dismounted.

ORACLE instance shut down.

SVRMGR> startup restrict

ORACLE instance started.

Total System Global Area 57124108 bytes

Fixed Size 70924 bytes

Variable Size 40198144 bytes

Database Buffers 16777216 bytes

Redo Buffers 77824 bytes

Database mounted.

Database opened.

SVRMGR> alter database backup controlfile to trace;

Statement processed.

SVRMGR>

SVRMGR> show parameter user_dump_dest

NAME TYPE VALUE

----------------------------------- ------- -------------------------

user_dump_dest string E:\ora816\admin\ora816\udump

Note :- Backup control file will generate in user dump destination as above. Check for the latest Ora<xxxxx>.trc . Rename this file to Ctrlprod.sql

SVRMGR> shutdown immediate;

Database closed.

Database dismounted.

ORACLE instance shut down.

Source – Production Instance/Server

Destination – Clone Instance /Server

Step 4: Copy all the parameter files (initsid.ora, configsid.ora ), Control files, Ctrlprod.sql ( created as above) and all data files to clone server . It is good to follow the OFA. If you are cloning a database on the same machine then create a different directory structure ( as OFA) for cloning instance and copied all the required files of primary instance here.

Step 4a : On Unix ( Let us say your cloning instance name is clone)

If you had followed OFA , your initsid.ora parameters files would be in $ORACLE_BASE/admin/clone/pfile/initclone.ora

and configsid.ora would be in $ORACLE_BASE/admin/clone/pfile/configclone.ora.

Create a symbolic link

Change the working directory to $ORACLE_HOME/dbs and create a symbolic link

$ ln –s $ORACLE_BASE/admin/clone/pfile/initclone.ora initclone.ora

Step 5 : On destination server

Change the following parameter in the initsid.ora of the cloning instance/server

InitSid.ora (initora816.ora) of the Source/production server.

InitSid.ora (initclone.ora) of the

destination/clone server.

db_name = "ora816"

instance_name = ora816

service_names = ora816

control_files = ("e:\ora816\oradata\ora816\control01.ctl", "f:\ora816\oradata\ora816\control02.ctl", "g:\ora816\oradata\ora816\control03.ctl")

Db_name= “clone”

Instance_name= clone

Service_name = clone

Control_file = (“C:\clone\control01.ctl”,”D:\clone\control02.ctl”)

The other parameter which is required to change is user_dump_dest, background_dump_dest,log_archive_dest

Oraxxxx.trc is copied from source/production instance to destination/clone instance and renamed it as ctrlclone.sql .

Edit ctrlclone.sql as follows.

Oraxxxx.trc in user dump dest of Source/Production instance

Ctrlclone.sql

STARTUP NOMOUNT

CREATE CONTROLFILE REUSE DATABASE "ORA816" NORESETLOGS ARCHIVELOG

MAXLOGFILES 32

MAXLOGMEMBERS 2

MAXDATAFILES 32

MAXINSTANCES 16

MAXLOGHISTORY 1815

LOGFILE

GROUP 1 'E:\ORA816\ORADATA\ORA816\REDO03.LOG' SIZE 1M,

GROUP 2 'E:\ORA816\ORADATA\ORA816\REDO02.LOG' SIZE 1M,

GROUP 3 'E:\ORA816\ORADATA\ORA816\REDO01.LOG' SIZE 1M

DATAFILE

'E:\ORA816\ORADATA\ORA816\SYSTEM01.DBF',

'E:\ORA816\ORADATA\ORA816\RBS01.DBF',

'E:\ORA816\ORADATA\ORA816\TEMP01.DBF',

'E:\ORA816\ORADATA\ORA816\TOOLS01.DBF',

'E:\ORA816\ORADATA\ORA816\INDX01.DBF',

'E:\ORA816\ORADATA\ORA816\DR01.DBF',

'E:\ORA816\DATABASE\NGAR5ORA81601.DBF',

'E:\ORA816\DATABASE\RBSTEST01.DBF'

CHARACTER SET WE8ISO8859P1

;

# Recovery is required if any of the datafiles are restored backups,

# or if the last shutdown was not normal or immediate.

RECOVER DATABASE

# All logs need archiving and a log switch is needed.

ALTER SYSTEM ARCHIVE LOG ALL;

# Database can now be opened normally.

ALTER DATABASE OPEN;

/* Delete everything upto startup nomount */

STARTUP NOMOUNT pfile=f:\clone\initclone.ora

CREATE CONTROLFILE set DATABASE "CLONE" resetlogs noarchivelog

MAXLOGFILES 32

MAXLOGMEMBERS 2

MAXDATAFILES 32

MAXINSTANCES 16

MAXLOGHISTORY 1815

LOGFILE

GROUP 1 'F:\CLONE\ORA816\REDO03.LOG'

SIZE 1M,

GROUP 2 'F:\CLONE\ORA816\REDO02.LOG'

SIZE 1M,

GROUP 3 'F:\CLONE\ORA816\REDO01.LOG'

SIZE 1M

DATAFILE

'F:\CLONE\ORA816\SYSTEM01.DBF',

'F:\CLONE\ORA816\RBS01.DBF',

'F:\CLONE\ORA816\TEMP01.DBF',

'F:\CLONE\ORA816\TOOLS01.DBF',

'F:\CLONE\ORA816\INDX01.DBF',

'F:\CLONE\ORA816\DR01.DBF', 'F:\CLONE\DATABASE\NGAR5ORA81601.DBF',

'F:\CLONE\DATABASE\RBSTEST01.DBF'

CHARACTER SET WE8ISO8859P1

;

# Recovery is required if any of the datafiles are restored backups,

# or if the last shutdown was not normal or immediate.

#RECOVER DATABASE

# All logs need archiving and a log switch is needed.

#ALTER SYSTEM ARCHIVE LOG ALL;

# Database can now be opened normally.

#ALTER DATABASE OPEN;

STEP 6 :-

ON NT :- You have to create a windows NT services as follows.

C:\>oradim -new -sid clone -srvc oracleserviceClone -intpwd oracle -startmode auto -pfile f:\clone\initclone.ora

ON Unix :-

(A) Change the working directory to /etc and edit the oratab file to put the entry for CLOBE instance.

(B) Setup login profile for the Oracle user having dba group.

ORACLE_SID=CLONE

Export ORACLE_SID

Or .oraenv

STEP 7 :- Create controlfile as follows :-

Check in the initclone.ora REMOTE_LOGIN_PASSWORDFILE is set to

   exclusive or shared.  If this is set, then a valid passwordfile

should exist in ORACLE_HOME/dbs or created using orapwd as

orapwd file=/u01/oracle/V816/dbs/orapwV722 password=oracle entries=1

where /u01/oracle/V816 is an oracle home

SVRMGR> @f:\clone\ctrlclone.sql

ORACLE instance started.

Total System Global Area 57123804 bytes

Fixed Size 70620 bytes

Variable Size 40198144 bytes

Database Buffers 16777216 bytes

Redo Buffers 77824 bytes

Statement processed.

STEP 8 :- Open the database in resetlog mode as follows.

SVRMGR> alter database open resetlogs;

Statement processed.

STEP 9 :- Shutdown the database in Normal mode

SVRMGR> connect internal/oracle

Connected.

SVRMGR> shutdown ;

Database closed.

Database dismounted.

ORACLE instance shut down.

STEP 10 :- Take the cold backup and start the database in archive/non archive mode.

Note :-

You cannot move datafiles from one operating system and use them on a different operating system. Therefore, it is not possible to clone a database running on SUN on an HP machine. You would have to use export/import.

Thanks for reading this article. Email me your comments or suggestions

Sameer Wadhwa

Wadhwa_S@Hotmail.com

SamWad@msn.com