RMAN Backup Setting

Contents:- Oracle Backup Retention Concept,  Configure Backup Setting, Show Existing Company Backup Policy

Retention Policy

A retention policy specifies which backup will be kept and for how long.

There are two types of retention policy

Recovery Window

Establishes a period of time within which point-in-time recovery is possible.

Rman> Configure retention policy to recovery window of <days> days;

If you are not using  a recovery catalog, then you should keep the recovery window time period <= the value of the control file parameter CONTROL_FILE_RECORD_KEEP_TIME to prevent the record of older backups from being overwritten in the control file. And if you are using a recovery catalog, then make sure that CONTROL_FILE_RECORD_KEEP_TIME is greater than the time period between catalog resynchronization.

Catalog Resynchronization happens when you

          Create a backup. In this case synchronization is done implicitly.

          Execute the resync catalog command.

Redundancy

Establishes a fixed number of backup that must be kept.

Rman> Configure retention policy to redundancy <copies>;

Disable Retention Policy

Rman >Configure retention policy to none;

Backup Setting

Show all Existing Backup Setting.

$> rman target /

Rman> show all;

Rman> show exclude;

Rman> show controlfile autobackup format;

Or

$> sqlplus sys as sysdba

Sql> select * from v$rman_configuration;

Configure New Backup Setting

$> rman target /

Controlfile Autobackup Setting

Rman> configure controlfile autobackup format for device type disk to ‘/u01/app/oracle/backup/controlfile/%F’;

With a control file autobackup, RMAN can recover the database even if the current control file, recovery catalog, and server parameter file are inaccessible. RMAN Can search for and restore the server parameter file or control file from that autobackup.

Use multiple Streams of data

Rman> configure device type sbt parallelism 3;

Parallelism is the number of streams of data that can be used to read from and write to the device. For example:- if the media manager has two tape drives available, then parallelism 2 would allow both tape drives to be used simultaneously for backup command using that media manager.

Use Clear option to reset to default setting.

Rman> configure retention policy to clear;

configure and allocating channels.

Rman> configure default device type to disk;

Rman> configure default device type to tape;

Configure backup setting for multiple copies of backup set

Rman> configure archivelog backup copies for device type disk to 2;

Rman> configure Datafile backup copies for device type disk to 2;

Rman> backup database plus archivelog ;    -- two copies of backup are made to two different disks.

Note:- This setting only applies to all backups except control file autobackups because the autobackup of a control file always produces one copy.

Note:- rman can make up to 4 backup copies of backup set simultaneously, each an exact duplicate of others. duplex backup set can only apply to backup set and can not apply to image copies.

Configure Backup Optimization

When enable backup optimization , the backup command skips files when identical files have already been backed up.

Rman> configure backup optimization on;

To Override backup optimization

Rman> backup device type disk backupset all force;

Configure Compression Backup

Backup compression can be used skip the backup of unallocated blocks as well as unused blocks.

Available compression algorithm are HIGH, MEDIUM,BASIC and LOW.

Rman> configure compression algorithm ‘HIGH/ MEDIUM/LOW/BASIC’;

Encryption Backup

Transparent Encryption:           With a Wallet (default)

Password Encryption:               With a password. ( no wallet)

Dual Mode Encryption              has both transparent and password encryption modes.

Spool backup

Rman> spool log to ‘/u01/app/oracle/backup/backup_log.txt’;