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Agenda
What is Recovery Manager? Automatic disk based recovery Optimized incremental backups Incrementally updated backups Just say no to shrinking backup windows A new twist to transportable tablespaces Q&A
Recovery Manager: Oracle’s Backup & Recovery Utility
Over 25 Man Years of Engineering Technology provides:
– 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 & 3rd party network backup products
Media Management Layer
Enterprise ManagerEnterprise Manager& 3& 3rdrd Party Tools Party Tools
Network
RecoveryRecoveryManagerManager
New World: Disk Based Data Recovery
Disk economics are close to tape
Disk is better than tape– Random access to any data
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
Backup and Recovery goes from hours to minutes
2000’s - 200 GB
1980’s - 200 MB
1000x increase
Flash Recovery Area 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
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
Disk limit is reached and a new file needs to be written
into the Flash Recovery Area
Backup Files
to be deleted
Archive Logs &Database File
Backups
Warning Issued to user
Space Pressure occurs
RMAN updates
list of files that
may be deleted
12
Oracle
delete files that
are no longer
required on
disk.
Flash Recovery
Area
Benefits to Using a Flash Recovery Area
Unifies the storage location of related recovery files
Manages the disk space allocated for recovery files automatically
Simplifies database administrator tasks Much faster backup Much faster restore Much more reliable due to inherent reliability of disks
Change Tracking File Optimizes incremental
backups– Track which blocks have
changed since last backup
Integrated change tracking file– Changed blocks are
tracked as redo is generated
– RMAN backup automatically uses changed block list
101100101011000011101001011010101110011
ChangeTracking File
Flash RecoveryArea
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/u101/changetrack/o1_mf_yzczmrr7_.chg‘];
– The Change Tracking Writer (CTWR) process– v$block_change_tracking view
STATUS
FILE
BYTES
Incremental Backup and Changed Tracking File
Benefits Faster
– Optimizes incremental backups to only backup those changed blocks directly
– Integrated with DB recovery and logging Better
– Uses less space since changes are tracked per block group
– RAC enabled Simpler
– Automatically integrates with backup and recovery – zero effort
Incrementally Updated Backups
Eliminates the need to perform a whole database backup. Reduces the time required for media recovery since the image
copy is updated with the latest block changes.
RMAN
RECOVER COPY OF DATAFILE
RMANincremental
backup
Initiate Merge
IncrementallyUpdated Backups
Eliminate Shrinking Backup Window Syndrome!
Fully automatic disk based backup and recovery
– Set it and Forget it
Nightly incremental backup rolls forward recovery area backup
– Changed blocks are tracked in production DB
Full scan is never needed– Dramatically faster (20x)– Blocks validated to prevent
corruption of backup copy
Use low cost disk array for recovery area
Two Independent Disk Systems
Flash RecoveryArea
Nightly ApplyValidatedIncremental
WeeklyArchiveTo Tape
DatabaseArea
Oracle Suggested Strategy
Easy & Reliable– Integrates the
Oracle DB 10g features
Fast Recovery Options
– Backup and Recovery goes from hours to minutes
Automated Disk Based Backup & Recovery Benefits
Much faster backup– Just propagate changes to recovery area– Dramatic difference for large databases
Much faster restore – Copy backup files from the Flash Recovery Area– Or simply use the copy in the Flash Recovery
Area Much more reliable due to inherent reliability of disks
– Tapes not needed for normal backup/recovery, only for archiving
Backup Management
List RMAN backups– View files included
in a backup set Perform maintenance
– Remove obsolete backups with a single click
What is Transportable Tablespace?
OS copyFile 1 File
2expdat.dmp
File 1 File
2expdat.dmp
2424
Mechanism to quickly move a tablespace across Oracle databases
Most efficient means to move bulk data between databases.
– File is simply copied at OS level
Oracle10g Cross Platform Transportable Tablespace
Solaris (SPARC)
Open VMS (Intel IA64)
Windows (Intel IA32/64)
Linux (Intel IA32/64)
AIX (PowerPC)
HP-UX (PA-RISC)
Tru64 UNIX (Alpha)
HP-UX (Intel IA64)
Small Endian Platforms Big Endian Platforms
Simple File Copy Within These
Simple File Copy Within These
High SpeedFile Convert
RMAN
Cross Platform Transportable Tablespace Benefits
Fast data distribution in Data Warehousing environment (data marts)
Used for publishing structured data (i.e. catalogs on CDs)
Sharing of read only tablespaces by heterogeneous systems
Allowing a database to be migrated from one platform to another
Creating Compressed Backups
Compression of archive logs and backupses using LZ based approach
The compressed backupset is not be usable with pre– Oracle Database 10g
RMAN> BACKUP COMPRESSED BACKUPSET DATABASE;
RMAN> CONFIGURE DEVICE TYPE DISK PARALLELISM 2
BACKUP TYPE TO COMPRESSED BACKUPSET;
Other Oracle10g Backup & Recovery Enhancements Restore tolerates missing or corrupt backup
– Automatically fails over to previous backup
Automated recovery through a previous point in time recovery
– 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
HA OTN: http://otn.oracle.com/deploy/availability
RMAN Discussion Forum http:// otn.oracle.com
MetaLink http:// MetaLink.oracle.com &Q U E S T I O N SQ U E S T I O N S
A N S W E R SA N S W E R S