Database Copying/Cloning

A database cloning procedure is especially useful for the DBA who wants to give his developers a full-sized TEST and DEV instance by cloning the PROD instance into the development server areas.

This Oracle clone procedure can be use to quickly migrate a system from one UNIX server to another.  It clones the Oracle database and this Oracle cloning procedures is often the fastest way to copy a Oracle database.

STEP 1: On the old system, go into SQL*Plus, sign on as SYSDBA and issue: “alter database backup controlfile to trace”. This will put the create database syntax in the trace file directory. The trace keyword tells oracle to generate a script containing a create controlfile command and store it in the trace directory identified in the user_dump_dest parameter of the init.ora file. It will look something like this:

    STARTUP NOMOUNT

    CREATE CONTROLFILE REUSE DATABASE "OLDLSQ" NORESETLOGS

    NOARCHIVELOG

    MAXLOGFILES 16

    MAXLOGMEMBERS 2

    MAXDATAFILES 240

    MAXINSTANCES 1

    MAXLOGHISTORY 113

    LOGFILE

    GROUP 1 ('/u03/oradata/oldlsq/log1a.dbf',

    '/u03/oradata/olslsq/log1b.dbf') SIZE 30M,

    GROUP 2 ('/u04/oradata/oldlsq/log2a.dbf',

    '/u04/oradata/oldlsq/log2b.dbf') SIZE 30M

    DATAFILE

    '/u01/oradata/oldlsq/system01.dbf',

    '/u01/oradata/oldlsq/mydatabase.dbf'

    ;

    # Recovery is required if any of the datafiles are restored

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

    RECOVER DATABASE

    # Database can now be opened normally.

    ALTER DATABASE OPEN;

 STEP 2: Shutdown the old database

 STEP 3: Copy all data files into the new directories on the new server. You may change the file names if you want, but you must edit the controlfile to reflect the new data files names on the new server.

    rcp /u01/oradata/oldlsq/* newhost:/u01/oradata/newlsq

    rcp /u01/oradata/oldlsq/* newhost:/u01/oradata/newlsq

    rcp /u03/oradata/oldlsq/* newhost:/u03/oradata/newlsq

    rcp /u04/oradata/oldlsq/* newhost:/u04/oradata/newlsq

 STEP 4: Copy and Edit the Control file – Using the output syntax from STEP 1, modify the controlfile creation script by changing the following:

 Old:

     CREATE CONTROLFILE REUSE DATABASE "OLDLSQ" NORESETLOGS

 New:

     CREATE CONTROLFILE SET DATABASE "NEWLSQ" RESETLOGS

 STEP 5: Remove the “recover database” and “alter database open” syntax

    # Recovery is required if any of the datafiles are restored

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

    RECOVER DATABASE

    # Database can now be opened normally.

    ALTER DATABASE OPEN;

STEP 6: Re-names of the data files names that have changed.

Save as db_create_controlfile.sql.

Old:

    DATAFILE

    '/u01/oradata/oldlsq/system01.dbf',

    '/u01/oradata/oldlsq/mydatabase.dbf'

New:

    DATAFILE

    '/u01/oradata/newlsq/system01.dbf',

    '/u01/oradata/newlsq/mydatabase.dbf'

STEP 7: Create the bdump, udump and cdump directories

    cd $DBA/admin

    mkdir newlsq

    cd newlsq

    mkdir bdump

    mkdir udump

    mkdir cdump

    mkdir pfile

 STEP 8: Copy-over the old init.ora file

     rcp $DBA/admin/olslsq/pfile/*.ora newhost:/u01/oracle/admin/newlsq/pfile

 STEP 9: Start the new database

     @db_create_controlfile.sql

 STEP 10: Place the new database in archivelog mode