Oracle – Cloning Database – Cold Cloning, Hot Cloning

Clone an Oracle Database using Cold Physical Backup

Database Name: troy

Source Database side: (Troy database)

Cold Backup Steps

1. Get the file path information using below query

Select name from v$datafile;

Select member from v$logfile;

Select name from v$controlfile;

2. Parameter file backup

If troy database running on spfile

Create pfile=/u01/backup/inittroy.ora from spfile;

If database running in pfile using os command to copy the pfile and placed in backup path.

3.Taken the control file backup

Alter database backup controlfile to trace as /u01/backup/control01.ora;

4.Shutdown immediate

5.Copy all the data files/log files using os command & placed in backup path.

6.Startup the database.

Clone Database side: (Clone database)

Database Name: Clone

Clone Database Steps:

1.Create the appropriate folder in corresponding path & placed the backup files in corresponding folder.(bdump,udump,create,pfile,cdump,oradata)

2.Change the init.ora parameter like control file path, dbname, instance name etc…

3.Create the password file using orapwd utility.

(Database in windows we need to create the service id using oradim utility)

4.Startup the Database in NOMOUNT stage.

5.Create the control file for cloning database.

Using backup controlfile trace to generate the create controlfile scripts.

Change the Database name & files path, also change ‘REUSE’ needs to be changed to ‘SET’.

CREATE CONTROLFILE SET DATABASE “clone” RESETLOGS FORCE LOGGING NOARCHIVELOG
MAXLOGFILES 50
MAXLOGMEMBERS 5
MAXDATAFILES 100
MAXINSTANCES 1
MAXLOGHISTORY 453
LOGFILE
GROUP 1 ‘/U01/oradata/clone/redo01.log’ SIZE 200M,
GROUP 2 ‘/U01/oradata/clone/redo02.log’ SIZE 200M,
GROUP 3 ‘/U01/oradata/clone/redo03.log’ SIZE 200M
DATAFILE
‘/U01/oradata/clone/system01.dbf’,
‘/U01/oradata/clone/undotbs01.dbf’,
‘/U01/oradata/clone/users01.dbf’,
CHARACTER SET WE8ISO8859P1;

Note: placed the script in sql prompt. Now controlfile created.

6.Now open the database.

Alter database open resetlogs;

Note: Check the logfile, datafiles & instance status

**********************************************************************************

Clone an Oracle Database using Hot Physical Backup

Database Name: troy

Database must be in Archive log mode.

Source Database side: (Troy database)

Hot Backup Steps:

1.Get the file path information using below query.

Select tablespace_name, file_name from dba_data_files order by 1;

2. Parameter file backup

If troy database running on spfile

Create pfile=/u01/backup/inittroy.ora from spfile;

If database running in pfile using os command to copy the pfile and placed in backup path.

3.Put the tablespace in begin backup mode Using os command to copy the datafiles belongs to begin backup mode tablespace & placed in backup path. (Refer below example)

4.Once copied the datafile, release the tablespace from begin backup mode to end backup

5.Repeat the steps 1-3 for all your tablespaces.

6.Taken the controlfile backup

Alter database backup controlfile to trace as /u01/backup/control01.ora;

7.Backup all your archive log files between the previous backup and the new backup as well.

Example:

Steps:

1.Alter tablespace system begin backup;

To ensure the begin backup mode tablespace using below query

Select * from v$backup; (refer the Change#, Time column)

2. Host cp /u01/oracle/raja/system1.DBF /u01/backup/system01.dbf using os command to copy the datafile.

3. Alter tablespace system end backup;

To ensure the begin backup mode tablespace using below query

Select * from v$backup;

Clone Database side: (Clone database)

Database Name: Clone

Clone Database Steps:

1. Create the appropriate folder in corresponding path & placed the backup files in corresponding folder.(bdump,udump,create,pfile,cdump,oradata)

2. Change the init.ora parameter like control file path, dbname, instance name etc…

3. Create the password file using orapwd utility.

(Database in windows we need to create the service id using oradim utility)

4.Startup the Database in NOMOUNT stage.

5.Create the control file for cloning database.

Using backup controlfile trace to generate the create controlfile scripts.

Change the Database name & files path, also change ‘REUSE’ needs to be changed to ‘SET’.

CREATE CONTROLFILE SET DATABASE “clone” RESETLOGS FORCE LOGGING NOARCHIVELOG
MAXLOGFILES 50
MAXLOGMEMBERS 5
MAXDATAFILES 100
MAXINSTANCES 1
MAXLOGHISTORY 453
LOGFILE
GROUP 1 ‘/U01/oradata/clone/redo01.log’ SIZE 200M,
GROUP 2 ‘/U01/oradata/clone/redo02.log’ SIZE 200M,
GROUP 3 ‘/U01/oradata/clone/redo03.log’ SIZE 200M
DATAFILE
‘/U01/oradata/clone/system01.dbf’,
‘/U01/oradata/clone/undotbs01.dbf’,
‘/U01/oradata/clone/users01.dbf’,
CHARACTER SET WE8ISO8859P1;

Note: placed the script in sql prompt. Now controlfile created.

6.Recover the database using controlfile.

Recover database using backup controlfile until cancel;

7.Now open the database.

Alter database open resetlogs;

Note: Check the logfile, datafiles status.

I Hope this article helped you to understand the cloning oracle database.Suggestions are welcome.