Home / server / Questions / 44202
Accepted
BIBD
Asked: 2009-07-23 10:45:25 +0800 CST

How do you clone an oracle instance?

  • 772

How do you clone an oracle instance? Basically, I want to end up copying it from d:\oracle\oldname to d:\oracle\newname.

I'm working with Oracle 10.2.

database oracle database-administration oracle10g

3 Answers

  1. Best Answer

    Look into using the RMAN DUPLICATE command. I believe this was introduced in 9i, but is certainly available in 10g. It takes care of all of those steps that used to be necessary when cloning manually such as renaming datafiles, recreating control files, resetting database name, etc.

    If you have a new directory structure for data and log files you can just permanently set the clone's startup parameters to convert these automatically to the new format/location by a string replacement specification. Cloning then becomes as simple as connecting to the target ("clone from"), aux ("clone to"), and RMAN catalog databases and issuing the RMAN command "DUPLICATE DATABASE to (myNewDBname)". You can also set the "until time" to bring the clone up to an earlier point in time.

    Oracle 11g adds the ability to clone directly from a live database.

    By the way, if you're not backing up with RMAN, then drop everything else and start doing this now!

    • 4

  2. I assume you want a different instance name on the clone ?,

    In many ways the easiest way may well be to use RMAN or your backup and restore software to do the job for you.

    I think it would be along the lines of:

    • Backup your database
    • Shutdown your database
    • Create a new database with the same SID as the original
    • Restore into the new database
    • export ORACLE_SID=newname
    • Change the pfile or spfile to reflect the new location of the control file
    • Generate a new password file orapwd file=orapw password=?? entries=5
    • Start the new database up
    • Start the old database up

    This is pieced together from memory and having a quick google, its been about 2 years since I did any serious work with oracle so I would not expect the above to be correct but it may set you off in the right direction.

    If you wanted the same instance on a different server I would recommend using NFS and a netapp and flexclones as they work wonderfully.

    • 0

  3. If you can get a cold or hot backup of your database:

    1. Copy cold/hot backup files to the new directory structure.
    2. Modify your init.ora file for the new instance.
    3. Issue STARTUP MOUNT logged on as sysdba user

    4. Run the following commands:

      conn / as sysdba

      STARTUP NOMOUNT CREATE CONTROLFILE REUSE SET DATABASE "NEWNAME" RESETLOGS NOARCHIVELOG MAXLOGFILES xx MAXLOGMEMBERS xx MAXDATAFILES xxx MAXINSTANCES xx MAXLOGHISTORY xxxx LOGFILE GROUP 1 'd:\oracle\NEWNAME\REDO01.LOG' SIZE XXM, --pick your redo log size
      GROUP 2 'd:\oracle\NEWNAME\REDO02.LOG' SIZE XXM,
      GROUP 3 'd:\oracle\NEWNAME\REDO03.LOG' SIZE XXM DATAFILE
      'd:\oracle\NEWNAME\SYSTEM.DBF',
      'd:\oracle\NEWNAME\undotbs.DBF',
      'd:\oracle\NEWNAME\USERS.DBF',
      'd:\oracle\NEWNAME\sysaux.DBF',
      'd:\oracle\NEWNAME\TOOLS.DBF' -- any other files in your database need to be renamed as well CHARACTER SET WE8ISO8859P1; -- adjust as necessary

      ALTER DATABASE OPEN RESETLOGS;

    and you'll probably want to do something like this as well:

    ALTER TABLESPACE TEMP ADD TEMPFILE 'd:\oracle\newname\temp.dbf' SIZE 20M REUSE AUTOEXTEND ON NEXT 20M MAXSIZE UNLIMITED;

    That should get you close...

    • 0