Oracle Recovery Manager RMAN 10 g Reloaded

Oracle Recovery Manager (RMAN) 10 g : Reloaded Boris Gurov Support Engineer Oracle Bulgaria

Agenda Ÿ What is Recovery Manager? Ÿ Automatic disk based recovery Ÿ Optimized incremental backups Ÿ Incrementally updated backups Ÿ Just say no to shrinking backup windows Ÿ A new twist to transportablespaces Ÿ Q&A

Recovery Manager: Oracle’s Backup & Recovery Utility Ÿ Over 25 Man Years of Engineering Technology provides: Recovery Manager Enterprise Manager & 3 rd Party Tools – – – Media Management Layer – Network – Intimate knowledge of database file formats and recovery procedures Manages and automates the backup, restore, and recovery process Creates and maintains backup policies Catalogs all backup and recovery activities Operates on-line and in parallel for fast processing Corrupt block detection during backup and restore and the ability to validate backups Integrated with Enterprise Manager & 3 rd party network backup products

New World: Disk Based Data Recovery 1980’s - 200 MB Ÿ Disk economics are close to tape Ÿ Disk is better than tape – 1000 x increase Random access to any data Ÿ We rearchitected our recovery strategy to take advantage of these economics – Random access allows us to backup and recover just the changes to the database Ÿ Backup and Recovery goes from hours to minutes 2000’s - 200 GB

Flash Recovery Area Ÿ Unified storage location for all recovery files and recovery related activities in an Oracle Database. – Centralized location for control files, online redo logs, archive logs, flashback logs, backups – A flash recovery area can be defined as a directory, file system, or ASM disk group – A single recovery area can be shared by more than one database Ÿ Minimize the number of initialization parameters to set when you create a database – Define a database area and flash recovery area location – Oracle creates and manages all files using OMF Database Area Flash Recovery Area

Flash Recovery Area Space Management Archive Logs & Database File Backups Flash Recovery Area Disk limit is reached and a new file needs to be written into the Flash Recovery Area Space Pressure occurs Warning Issued to user RMAN updates list of files that may be deleted 1 2 Backup Files to be deleted Oracle delete files that are no longer required on disk.

Benefits to Using a Flash Recovery Area Ÿ Unifies the storage location of related recovery files Ÿ Manages the disk space allocated for recovery files automatically Ÿ Simplifies database administrator tasks Ÿ Much faster backup Ÿ Much faster restore Ÿ Much more reliable due to inherent reliability of disks

Change Tracking File Flash Recovery Area 1011001010110 0001110100101 1010101110011 Change Tracking File Ÿ Optimizes incremental backups – Track which blocks have changed since last backup Ÿ Integrated change tracking file – Changed blocks are tracked as redo is generated – RMAN backup automatically uses changed block list

The Size of the Change Tracking File • Approximately 1/250000 of the total size of the database • Depends on the number of the threads in RAC environment • Depends on the number of the old backups (max 8 backups are tracked)

Enabling Block Change Tracking – ALTER DATABASE ENABLE BLOCK CHANGE TRACKING [USING FILE ‘/oracle/u 101/changetrack/o 1_mf_yzczmrr 7_. chg‘]; – The Change Tracking Writer (CTWR) process – v$block_change_tracking view STATUS FILE BYTES

Incremental Backup and Changed Tracking File Benefits Ÿ Faster – Optimizes incremental backups to only backup those changed blocks directly – Integrated with DB recovery and logging Ÿ Better – Uses less space since changes are tracked per block group – RAC enabled Ÿ Simpler – Automatically integrates with backup and recovery – zero effort

Incrementally Updated Backups RMAN incremental backup Incrementally Updated Backups RMAN RECOVER COPY OF DATAFILE Initiate Merge Ÿ Eliminates the need to perform a whole database backup. Ÿ Reduces the time required for media recovery since the image copy is updated with the latest block changes.

Eliminate Shrinking Backup Window Syndrome! Ÿ Fully automatic disk based backup and recovery – Set it and Forget it Ÿ Nightly incremental backup rolls forward recovery area backup – Database Area Nightly Flash Recovery Apply Area Validated Incremental Weekly Archive To Tape Two Independent Disk Systems Changed blocks are tracked in production DB Ÿ Full scan is never needed – – Dramatically faster (20 x) Blocks validated to prevent corruption of backup copy Ÿ Use low cost disk array for recovery area

Oracle Suggested Strategy Ÿ Easy & Reliable – Integrates the Oracle DB 10 g features Ÿ Fast Recovery Options – Backup and Recovery goes from hours to minutes

Automated Disk Based Backup & Recovery Benefits Ÿ Much faster backup – Just propagate changes to recovery area – Dramatic difference for large databases Ÿ Much faster restore – Copy backup files from the Flash Recovery Area – Or simply use the copy in the Flash Recovery Area Ÿ Much more reliable due to inherent reliability of disks – Tapes not needed for normal backup/recovery, only for archiving

Backup Management Ÿ List RMAN backups – View files included in a backup set Ÿ Perform maintenance – Remove obsolete backups with a single click

What is Transportable Tablespace? Ÿ Mechanism to quickly move a tablespace across Oracle databases Ÿ Most efficient means to move bulk data between databases. – File is simply copied at OS level File 1 File 2 OS copy expdat. dmp File 1 File 2 expdat. dmp 24

Oracle 10 g Cross Platform Transportable Tablespace Small Endian Platforms Big Endian Platforms Linux (Intel IA 32/64) Windows (Intel IA 32/64) Open VMS (Intel IA 64) Tru 64 UNIX (Alpha) Simple File Copy Within These High Speed File Convert RMAN Solaris (SPARC) HP-UX (Intel IA 64) HP-UX (PA-RISC) AIX (Power. PC) Simple File Copy Within These

Cross Platform Transportable Tablespace Benefits Ÿ Fast data distribution in Data Warehousing environment (data marts) Ÿ Used for publishing structured data (i. e. catalogs on CDs) Ÿ Sharing of read only tablespaces by heterogeneous systems Ÿ Allowing a database to be migrated from one platform to another

Creating Compressed Backups Ÿ Compression of archive logs and backupses using LZ based approach Ÿ The compressed backupset is not be usable with pre– Oracle Database 10 g Ÿ RMAN> BACKUP COMPRESSED BACKUPSET DATABASE; Ÿ RMAN> CONFIGURE DEVICE TYPE DISK PARALLELISM 2 Ÿ BACKUP TYPE TO COMPRESSED BACKUPSET;

Other Oracle 10 g Backup & Recovery Enhancements Ÿ Restore tolerates missing or corrupt backup – Automatically fails over to previous backup Ÿ Automated recovery through a previous point in time recovery – Ÿ Ÿ Ÿ Recovery through resetlogs Fully automated tablespace point-in-time recovery Automatic channel failover on backup or restore Time window based throttling of backups Tablespace Rename Drop Database

Resources Ÿ HA OTN: http: //otn. oracle. com/deploy/availability Ÿ RMAN Discussion Forum http: // otn. oracle. com Ÿ Meta. Link http: // Meta. Link. oracle. com & QUESTIONS ANSWERS