How to create “Cold” RMAN Backup

 

This blog entry describes how to take rman backup of a database with NOARCHIVELOG mode. The only option you have to take backup of a NOARCHIVELOG mode database is to take consistent whole database backup.

The characteristic of a consistent backup is as under:

• All read/write datafiles and control files are checkpointed with the same system change number (SCN)
• A consistent backup does not need recovery after it is restored as all files in the backup are guaranteed to contain all changes up to the same SCN.

The steps involved in taking consistent backup as as under:

• Make sure the database is shutdown properly.
• If the database is not shut down consistently, for example, an instance fails or you issue a “shutdown abort” statement, then the datafiles are always inconsistent and hence your restore will fail. The script is shutting down the database twice as to ensure that the datafiles are in consistent state.
• Startup the database in mount option
• Configure the location where you need to take the backup
• The script is backing up the database on an disk at ‘backupPool/backup’ directory
• Configure autobackup of controlfile and specify a location where control file will be backed up.
• Backup the complete database

Here is the script to take cold rman backup:

#!/bin/sh
echo "Taking backup of $ORACLE_SID\n"
#rman target /  log=backupbench.log << !

shutdown immediate ;
startup  pfile=p_build.ora force dba;
shutdown immediate;
startup pfile=p_build.ora mount ;

configure device type disk parallelism 15 backup type to  backupset ;
configure channel device type disk format '/backupPool/backup/ora_df%t_s%s_s%p' ;
configure controlfile autobackup on ;
configure controlfile autobackup format for device type  disk to  '/backupPool/backup/cf_%F' ;

backup database tag 'JGD_create';
alter database open;
exit
!