Control File Multiplexing , Recovery

Contents:- Control File Multiplexing, Recovery of  Control File in Difference Ways

Control File Multiplexing 

Earlier and Upto 11g R1

Steps

SQL> Shutdown Immediate

In Widows Physically copy and paste control file.

Or in linux

SQL> cp ‘/u01/app/oracle/oradata/control01.ctl’  ‘/u01/app/oracle/oradata/control02.ctl’

Sql> Startup nomount

SQL> Alter system set control_files=/u01/app/oracle/oradata/control01.ctl’,‘/u01/app/oracle/oradata/control02.ctl’

Sql> Shutdown immediate

Sql > Startup

Or

After 11g R2

Steps

Take Backup of your spfile.

Sql> Create pfile=’/u01/app/oracle/backup/initstc.ora’ from spfile;

Update control_files parameter for the new control file.

Sql> alter system set control_files= '+DATA/orcl/controlfile/current.271.867278417','+DATA','+FLASH/orcl/controlfile/current.259.867278417' scope=spfile;

Sql> shutdown immediate

Sql> startup nomount

Create new control file using RMAN.

$> rman target /

$> restore controlfile from '+DATA/orcl/controlfile/current.271.867278417';

Update the SPFILE with the new control file name (that you will found in your data disk because you have given that disk name in control_files parameter in step 2)

Sql> alter system set control_files='+DATA/orcl/controlfile/current.271.867278417','+DATA/orcl/controlfile/current.264.867368249','+FLASH/orcl/controlfile/current.259.867278417' scope=spfile;

Sql> startup force

Sql> show parameter control_files

Thanks you . Congrats You multiplexed your control Files.

                                     
Control File Recovery

When at Least One Control File is Available

Two Way Recovery

1^st Way Recovery

          Before 11g R2

          Sql> shutdown immediate

          Sql> cp ‘/u01/app/oracle/oradata/control02.ctl’ ‘/u01/app/oracle/oradata/control01.ctl’;

          Sql> startup

          After 11g R2

  

          Sql> shut immediate

  

          Sql> startup nomount

          $>rman target /

          $> restore controlfile from '+DATA/orcl/controlfile/current.271.867278417';

sql>alter database mount;

          sql>alter database open;

          2nd way: Control file location remove from parameter file.

          Sql>shut immediate

          Sql>startup nomount

          Sql> alter system set control_files='D:\APP\XP\ORADATA\ORCL1\CONTROL01.CTL','D:\APP\XP\FLASH_RECOVERY_AREA\ORCL1\CONTROL02.CTL' scope=spfile;

          Sql> shut immediate

          Sql> startup

Recovery after lost of all control file using RMAN when catalog configured

Steps

Run

{

Shutdown immediate;

Startup mount;

Allocate channel c1 device type disk;

Restore controlfile from autobackup;

Sql ‘alter database mount’;

Recover database;

Sql ‘alter database open resetlogs’;

}

Recovery after lost of all control file using Control File backup to trace

Steps

Sql> alter session set tracefile_identifier=abc;

Sql>alter database backup controlfile to trace;

Open this abc.trc script and from that create script for controlfile re-create

Sql> shutdown immediate

Sql> startup nomount

Sql> @controlfile_recreate script

Recovery after lost of all control file using RMAN Using Snapshot Controlfile.

Steps

$> rman target /

Rman>run

{

Shutdown immediate;

Startup nomount;

Allocate channel ch type disk;

Restore controlfile from ‘snapshot_controlfile_path’;

alter database mount;

Recover database;

Alter database open resetlogs;

}

Recovery after lost of all control file and spfile.

Steps

$>rman target /

Rman>sql ‘shutdown abort’;

Rman>run

{

Startup nomount force;

Restore spfile from autobackup;

Shutdown immediate;

Startup nomount;

Restore controlfile from autobackup;

Alter database mount;

Alter database open resetlogs;

}

Recover all lost control file when catalog is not configured\

Steps

$>. Oraenv

Orcl

$>rman target /

Rman>shutdown immediate

Rman>startup nomount

Rman>set dbid=123456789;

Rman>restore controlfile from autobackup;