PROD Hot Oracle Database Cloning Without RMAN

Hot database cloning is ideal for 24/7 production databases where downtime is not an option. This method uses the hot backup mode to clone a database while it is running — no RMAN required, no database shutdown needed.

In this guide, we’ll demonstrate hot cloning of a database named PROD using SQL*Plus and basic OS utilities like scp.

Prerequisites

Archivelog mode must be enabled.
Sufficient space on target host.
SSH access between source and target.
Consistent file paths between source and target (or adjustments in init.ora and controlfile script).

Source & Clone Configuration

Source DB SID: PROD
Clone DB SID: PROD
File paths are the same on both systems.

Step 1: Clone the Parameter File (`init.ora`)

On the source:


SQL> create pfile from spfile;

Then, copy it to the target server:


scp $ORACLE_HOME/dbs/initPROD.ora oracle@funclonedb.lab:$ORACLE_HOME/dbs/

On the target, edit initPROD.ora as needed:


cat $ORACLE_HOME/dbs/initPROD.ora

Ensure directories for:

Control files
Audit dump (adump)

Create them if missing:


mkdir -p /u01/db_files/PROD/control
mkdir -p /u01/db_files/PROD/adump

Step 2: Clone the Controlfile (Trace Method)

On the source:


SQL> alter database backup controlfile to trace as '/tmp/PROD_ctl.sql' 
REUSE RESETLOGS;

Copy the controlfile trace to the target:


scp /tmp/PROD_ctl.sql oracle@funclonedb.lab:/tmp/

Edit the controlfile trace on the target:


vi /tmp/PROD_ctl.sql

Clean it up:

Delete everything before CREATE CONTROLFILE
Delete everything after the last ;

You should retain something like:


CREATE CONTROLFILE REUSE DATABASE "PROD" RESETLOGS NOARCHIVELOG
  MAXLOGFILES 16
  MAXLOGMEMBERS 3
  MAXDATAFILES 100
  MAXINSTANCES 8
  MAXLOGHISTORY 292
LOGFILE
  GROUP 1 '/u01/db_files/PROD/redo01.log' SIZE 200M,
  GROUP 2 '/u01/db_files/PROD/redo02.log' SIZE 200M,
  GROUP 3 '/u01/db_files/PROD/redo03.log' SIZE 200M
DATAFILE
  '/u01/db_files/PROD/system01.dbf',
  '/u01/db_files/PROD/sysaux01.dbf',
  '/u01/db_files/PROD/undotbs01.dbf',
  '/u01/db_files/PROD/users01.dbf'
CHARACTER SET AL32UTF8;

Step 3: Clone the Datafiles

3.1 Put DB in Backup Mode


SQL> alter system switch logfile;
SQL> alter database begin backup;

3.2 Copy Datafiles & Redo Logs


scp /u01/db_files/PROD/*log oracle@funclonedb.lab:/u01/db_files/PROD/
scp /u01/db_files/PROD/*.dbf oracle@funclonedb.lab:/u01/db_files/PROD/

3.3 End Backup Mode


SQL> alter database end backup;
SQL> alter system switch logfile;
SQL> archive log list;

3.4 Copy Archivelogs

Copy all archivelogs generated between begin backup and end backup to the same location on the target:


scp /u02/PROD/archivelog/* oracle@funclonedb.lab:/u02/PROD/archivelog/

Step 4: Mount and Recover Clone DB

4.1 Startup and Mount


sqlplus / as sysdba
SQL> startup nomount;
SQL> @/tmp/PROD_ctl.sql
SQL> alter database mount;

4.2 Recover Database


SQL> recover database using backup controlfile until cancel;

Feed the required archive logs when prompted. Continue hitting ENTER until prompted to type CANCEL.

4.3 Open Clone Database


SQL> alter database open resetlogs;

Hot Clone Complete

We’ve now created a fully functional clone of the PROD database without shutting it down and without using RMAN.

Please do like and subscribe to my youtube channel: https://www.youtube.com/@foalabs If you like this post please follow,share and comment

PROD Hot Oracle Database Cloning Without RMAN