Advanced RMAN

Rman is powerfull to for Oracle Backup, it has many features but little known. this post covered 11gR1 and 11gR2.

• Rman Recovery manager tool, could be backup up database, datafile, tablespace and archivelog
• All commands necessary to end with semicolon
• Rman can be used for both hot or cold backups. But database must be archivelog mode for host backups  as you know.

• In 11g rman REDUCE the size of backup with :
• skips the undo data for committed transactions.
• 10g backup 
•  at TAPE = once used blocks (ou) +used now blocks (u) +never used (nu)
• at DISK =  once used blocks (ou) +used now blocks (u)
• 11g backup
• at TAPE =  (o.u)+ (u)
• at DISK  = (u)
• Datafiles can  have many to many backup pices , Backup pices can have many to one Backup sets  and a datafile cant be split accross the backupsets
• 11g RMAN Read and Restore parallel.

• Incremental backups checks for used blocks, so it can check it he blocks have been backed up before.
• It can  backup only changed blocks
• Reducing backup size, time, I/O and CPU
• Level 0 Full Backup
• Level 1 changed since last level 1
•  Incremental doesnt care blocks are logging and data exist on undo or redo.
• Can be compressed.

• %d name of the database
• %D day of the Date
• %M month number
• %Y yerar
• %t time from reference point
• %T YYYYMMDD
• %n tablespace name
• %p backup piece number
• %s backupset number
• %U cover all parameters.

• Block Media Recovery
• 11gR1 recover datafile parameter is deprecated so we must use !
• blockrecover datafile DF# block  BLOCK#;

• Flash Recovery Area
• We have to define 2 initialization parameters;
• db_recovery_file_dest='+ORAFLASH' or '/ORAFLASH'
• db_recovery_file_dest_size = 10G

• Image Copies
• copies all blocks used or not
• command includes as copy
• Image copy backup is simple rman doesnt have to read file and restoring is simplier with no reconstruction
• merge is possible 
• !you tahe a imgae copy backup every sunday and incremental merge every day.
• Compression ?
• you cant backup to tape. you can backup only disk.

• Regular backup
• only used blocks are backed up so size is smaller than image copy
• time is short than image copy
• compression possible
• disk and tape backup is possible

• Compression
• how compressi,on do this;Default algorithm method is BZIP2.
• ABC123
• ABC789
• ABC223 SO GET THE ABC AS SYMBOL & and writes data to disk &123, &789 ....
• show compression algorithm;
• CONFIGURE COMPRESSION ALGORITHM 'BZIP2'; #default;
• There is another algorithm avaible in 11gR1-  ZLIB2 ( cpu usage is less then BZIP2)  but it requires advanced compression option.

• Trace and debug and logging
• You can use trace and debugging command at rman
• rman target=/ debug=all trace=rmantrace1.trc
• end of backup  you can read  #vi rmantrace1.trc
• rman target=/ log=rman1.log ( append is possible )
• rman target=/ log=rman1.log append
• rman target=/ log=rman1.log checksyntax
• v$rman_output
• v$rman_backup_job
• v$rman_backup_job_details

• Duplicating Database
• 10g needs connection to primary and backup for duplicate via rman
• 11gR1 needs connect to primary but backup not necessary from active DB
• 11gR2 from backup alone but no connection to primary needed. ***********

• Health checks (11g)
• RMAN >list failure
• RMAN >advise  failure
• RMAN >repair  failure preview

• Security
• Oracle RMAN can encrypt an entire database backup using one of these three methods:
• Local TDE master encryption key
• Passphrase
• Hybrid  : Passphrase and  Local TDE master encryption key
• Wallet ( alter system set encryption wallet open authenticated by "ilknur";
• you can store table encryption key SYS.ENC$ table.

 Make sure directory
$ORACLE_BASE/admin/$ORACLE_SID/wallet exists
set enc key password : key.sql
open the wallet : wallo.sql
close the wallet : wallo.sql


more information rman backup security: http://www.oracle.com/technetwork/database/security/index-095354.html