RMAN Configuration Demystified: A Practical Deep Dive for DBAs – Part 2

 

RMAN Configuration Demystified: A Practical Deep Dive for DBAs – Part 2

 

RMAN > CONFIGURE DEVICE TYPE DISK PARALLELISM 2;

 

• RMAN opens 2 channels to write to disk simultaneously.
• This improves backup/restore speed, especially for large databases or multiple datafiles.
• Each channel can operate independently, writing to different backup pieces.

 

RMAN >CONFIGURE DEVICE TYPE SBT PARALLELISM 2;

 

·         RMAN will use 2 channels to send backup data to tape drives in parallel.

·         This improves throughput (faster backups/restores) especially when:

·         You have multiple tape drives.

·         Your tape infrastructure supports concurrent streams.

 

RMAN >CONFIGURE CHANNEL DEVICE TYPE DISK FORMAT '/backup/orabackup/ora_df%t_s%s_s%p';

 

·         Sets the backup file naming format for disk backups.

·         %t represents four byte time stamp, %s with the backup set number, and %p with the backup piece number.

 

RMAN >CONFIGURE CHANNEL DEVICE TYPE DISK MAXPIECESIZE 2G;

 

·         RMAN Limits maximum size of a backup piece to 2 GB.

 

RMAN >CONFIGURE CHANNEL DEVICE TYPE DISK FORMAT ‘/tmp/%U’;

 

·         Overrides previous disk format to /tmp/%U. (%U = unique filename)

 

RMAN >CONFIGURE CHANNEL DEVICE TYPE DISK FORMAT ‘/disk1/%U’, ‘/disk2/%U’;

 

Defines where and how RMAN should name the backup files:

• %U is a substitution variable that generates a unique file name.
• RMAN will alternate writing backup pieces between /disk1/ and /disk2/ paths.
• This provides load balancing across multiple directories/disks.

 

RMAN >CONFIGURE DEVICE TYPE <DISK | SBT> BACKUP TYPE TO COMPRESSED BACKUPSET;

 

This Configures RMAN to always create compressed backup sets instead of regular backup sets or image copies.

 

RMAN >CONFIGURE CONTROLFILE AUTOBACKUP ON;

 

This is used to enable automatic backup of the control file and the server parameter file (SPFILE) every time an RMAN backup is run or a structural change is made to the database.

 

RMAN >CONFIGURE CONTROLFILE AUTOBACKUP FORMAT FOR DEVICE TYPE DISK TO '/u01/orclbackup/ora_cf%F';

 

This sets a custom format for automatic control file and SPFILE backups when the device type is DISK.

%F Combines the DBID, day, month, year, and sequence into a unique and repeatable generated name

 

RMAN >CONFIGURE CONTROLFILE AUTOBACKUP FORMAT FOR DEVICE TYPE DISK TO '+DATA/%F';

 

This is used to configure automatic control file and SPFILE backups to be stored in an Oracle ASM disk group named +DATA

 

RMAN >CONFIGURE BACKUP OPTIMIZATION ON;

 

It enables backup optimization, which helps avoid backing up files that haven't changed since the last backup.

With BACKUP OPTIMIZATION ON, RMAN will skip backing up:

• Datafiles that are:
• part of a previous backup of the same file
• not changed since that backup
• Archived redo logs that were already backed up to the same device type
• Control files and SPFILEs that are unchanged

RMAN >CONFIGURE DATAFILE BACKUP COPIES FOR DEVICE TYPE SBT TO 2;

 

·         This command instructs RMAN to create 2 identical copies of each datafile backup when backing up to SBT (tape).

·         It will write 2 separate backup sets, each containing the same datafiles.

·         This increases redundancy — useful for offsite + onsite storage, or general fault tolerance.

 

RMAN >CONFIGURE ARCHIVELOG BACKUP COPIES FOR DEVICE TYPE SBT TO 2;

 

·         This tells RMAN to create 2 identical copies of each archived redo log backup when backing up to SBT (tape).

·         It writes them as separate backup sets (not just duplicated files in the same set)

 

RMAN >CONFIGURE DATAFILE BACKUP COPIES FOR DEVICE TYPE DISK TO 2;

 

·         It configures RMAN to create 2 identical backup copies of each datafile when backing up to disk.

·         Each copy is a complete, usable backup of the datafile.

·         This provides redundancy in case one backup file is lost or corrupted.