Database Cloning Using Cold Backup

DATABASE CLONING USING COLD BACKUP | LINUX

CLONING ORACLE DATABASE FROM SERVER TO SERVER

ABOUT DATABASE CLONING

Database cloning is creating a Identical copy of existing

database. It can be done on separate hosts or on the same

host.

WHY CLONING ?

Every company will have PRODUCTION | TESTING| DEVELOPMENT

database. Some times development and production

environment there will become need to transport the entire

database from one physical machine to another. This copy may

be used for development, production testing, beta testing,

etc ..

1) If DBA wants to change dbname or DBID of the database.

2) Relocating an Oracle database to another machine.

3) Moving Oracle database to new Storage media.

THREE WAYS TO CLONE A DATABASE

COLD CLONING HOT CLONING RMAN CLONING

This article is intended as a brief guide to clone Oracle

database from server to server. I will show how to clone

Exploring the Oracle DBA Technology by Gunasekaran ,Thiyagu


database using cold cloning. Cold cloning is very easier to

clone by using OS commands.

Cold cloning does NOT require database recovery because the

source database is shut down normally before the image is

created.

COLD BACKUP CLONING SAME DIRECTORY STRUCTURE.

BUT DIFFERENT SERVER

SOURCE DATABASE : orcl

TARGET DATABASE : clone

SOURCE IP : 192.168.1.200 SERVER01

TARGET IP : 192.168.1.168 SERVER02

SOURCE DATABASE FILES PATH : /u01/app/oracle/oradata/orcl

TARGET DATABASE FILES PATH : /u01/app/oracle/oradata/clone

CHECKING IPADDRESS FOR SOURCE MACHINE - SERVER01

$ /sbin/ifconfig

eth0 Link encap:Ethernet HWaddr 00:0C:29:23:9F:47

inet addr:192.168.1.200 Bcast:192.168.1.255 Mask:255.255.255.0 . .. [ Trimmed ]

CHECKING IPADDRESS FOR TARGET MACHINE - SERVER02



$ /sbin/ifconfig

eth0 Link encap:Ethernet HWaddr 00:0C:29:01:A9:D2

inet addr:192.168.1.168 Bcast:192.168.1.255 Mask:255.255.255.0 . .. [ Trimmed ]

STARTUP THE SOURCE DATABASE ( IF NOT OPEN )

$ export ORACLE_SID=orcl

$ sqlplus /nolog

SQL> conn /as sysdba

Connected to an idle instance.

SQL> startup

ORACLE instance started....

[ Trimmed ].

Database opened.

IDENTIFY THE PATH AND NAMES OF DATABASE FILES

( DATAFILES, CONTROL FILES, AND REDO LOG FILES )

SQL> select name from v$datafile;

SQL> select name from v$controlfile;



SQL> select member from v$logfile;

http://www.scribd.com/doc/187563299/Identify-the-Path-and-Names-of-Database-Files

TAKE CONTROL FILE BACKUP

Create a control file for the clone database. To do this, from the

source database and request a dump of the current control

file. The file will require extensive editing before it can be used.

By default , trace goes to USER_DUMP_DEST. We can check the

path. SQL> show parameter user_dump_dest ;

I am taking trace file at specific path ---

SQL> alter database backup controlfile to trace as 'path ' ;

alter database backup controlfile to trace as

'/u01/backup/ctrl.sql'; Database altered.

PARAMETER FILE BACKUP

If database is using pfile, use OS command to copy the pfile

to a backup location. In my case i am using spfile. I will

create pfile from the spfile.


http://www.scribd.com/doc/187563299/Identify-the-Path-and-Names-of-Database-Files


PLEASE NOTE

Once created, the new pfile will need to be edited. The cloned

database will be new name, this will need to be changed .

Review the contents of the file and make alterations as

necessary.

SHUTDON THE SOURCE DATABASE

SQL> shut immediate;

Database closed.

Database dismounted.

ORACLE instance shut down.

CREATE DIRECTORIES FOR CLONE DATABASE - SERVER02



MOVING TRACE FILE AND PFILE FROM SOURCE TO TARGET

SQL> cd /u01/backup/

$ ls -l

-rw-r--r-- 1 oracle oinstall 5799 Oct 24 00:07 ctrl.sql

-rw-r--r-- 1 oracle oinstall 995 Oct 24 00:29 initclone.ora

TAKING CLOD BACKUP OF THE SOURCE DATABASE



I RECEIVED ALL DATABASE FILES - IN SERVER02



EDIT THE CLONE DATABASE PARAMETER FILE

$ cd $ORACLE_HOME/dbs

[oracle@oel5 dbs]$ ls -l clone*

-rw-r--r-- 1 oracle oinstall 995 Oct 24 01:16 clone.ora



As i said , pfile will need to be edited so i want to edit it as

per target database (clone). See both screen shots.

Now i am going to edit trace file located at $HOME

Remove all lines from the top of the file up to but not including

the second 'STARTUP MOUNT

Remove any lines that start with --

Remove any lines that start with a #

Remove any blank lines in the 'CREATE CONTROLFILE' section.



Remove the line 'RECOVER DATABASE USING BACKUP CONTROLFILE'

Move to the top of the file to the 'CREATE CONTROLFILE' line. The word

'REUSE' needs to be changed to 'SET'. Decide whether the database will be

put into archivelog mode or not.

HOW THE FILE WOULD LOOK FOR A CLONE DATABASE

POINTS TO REMEMBER

Cold cloning does NOT require database recovery because the

source database is shut down normally before the image is

created. So i choosing NOARCHIVELOG mode. If you wish to

change , just change as ARCHIVELOG . This is suffice.



Edit the /etc/oratab (or /opt/oracle/oratab) and add an entry for

the clone database. This is also part of the database

environment.

CREATE A PASSWORD FILE at $ORACLE_HOME/dbs

Create password file using oratab utility

$ cd $ORACLE_HOME/dbs

$ orapwd file=orapw$ORACLE_SID password=<password> entries=n

$ orapwd file=orapwclone password=clone entries=3

Oracle exatly needs $ORACLE_SID PREFIX init. so i am

changing

parameter file name from initclonedb.ora to initclone.ora

$ ls -l initclone*

-rw-r--r-- 1 oracle oinstall 1037 Oct 23 00:36 initclonedb.ora

[oracle@oel5 dbs]$ mv initclonedb.ora initclone.ora

ls -l initclone*

-rw-r--r-- 1 oracle oinstall 1037 Oct 23 00:36 initclone.ora



CHECKING CLONE DATABASE FILES

CHECK DBID , DBNAME fOR TARGET DATABASE



Above screen for target database. We need to change DBID because it is

having source database DBID. HOW TO CHANGE DBID CLICK HERE ..

SCREEN SHOT FOR SOURCE DATABASE

PERFORM FEW CHECKS IN TARGET DATABASE

Make sure all datafiles are okay ..

SQL> select distinct status from v$datafile;


http://www.scribd.com/doc/187559341/How-to-Change-Dbname-Dbid-and-Instance-Name


STATUS

ONLINE

SYSTEM

It should return only ONLINE and SYSTEM.

SQL> create spfile from pfile='/ path of the pfile ' ;

File created.

SQL> startup force;

ORACLE instance started.

...

[Trimmed].

POINTS TO NOTE :

Change the database ID If RMAN is going to be used to back-

up the database, the database ID must be changed. If RMAN

isn't going to be used, there is no harm in changing the ID.



Now , Cloned destination database is ready to be

used.

POINTS TO NOTE :

During cold clone , we can do EITHER restore (copy back)

control file or create control file . Yes , if we have same

locations in clone server as source, then we do NOT need to

create control file again just copy all files then start

database.

REFERENCE LINK :

http://www.scribd.com/doc/187550497/Cloning-Oracle-Database-From-Server-to-

Server


http://www.scribd.com/doc/187550497/Cloning-Oracle-Database-From-Server-to-Server

http://www.scribd.com/doc/187550497/Cloning-Oracle-Database-From-Server-to-Server

Date post:	21-Jan-2016
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Database Cloning Using Cold Backup

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