Download Oracle Recovery Manager (RMAN) 10g

Oracle Recovery Manager
(RMAN) 10g : Reloaded
Boris Gurov
Support Engineer
Oracle Bulgaria
Agenda
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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:
Recovery
Manager
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Enterprise Manager
& 3rd Party Tools
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Media Management Layer
–
Network
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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
New World:
Disk Based Data Recovery
1980’s - 200 MB
 Disk economics are close to tape
 Disk is better than tape
–
1000x increase
Random access to any data
 We rearchitected our recovery
strategy to take advantage of
these economics
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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
Flash Recovery Area
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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
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
 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
Flash Recovery
Area
1011001010110
0001110100101
1010101110011
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
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
RMAN
incremental
backup
Incrementally
Updated Backups
RMAN
RECOVER COPY OF
DATAFILE
Initiate Merge
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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.
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
–
Database
Area
Nightly Flash Recovery
Apply
Area
Validated
Incremental
Weekly
Archive
To Tape
Two Independent Disk Systems
Changed blocks are tracked
in production DB
 Full scan is never needed
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Dramatically faster (20x)
Blocks validated to prevent
corruption of backup copy
 Use low cost disk array for
recovery area
Oracle Suggested Strategy
 Easy & Reliable
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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?
 Mechanism to quickly move a tablespace
across Oracle databases
 Most efficient means to move bulk data
between databases.
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File is simply copied at OS level
File
1 File
2
OS copy
expdat.dmp
File
1 File
2
expdat.dmp
24
Oracle10g Cross Platform
Transportable Tablespace
Small Endian Platforms
Big Endian Platforms
Linux (Intel IA32/64)
Windows (Intel IA32/64)
High Speed
File Convert
Open VMS (Intel IA64)
Tru64 UNIX (Alpha)
Simple File Copy Within These
Solaris
(SPARC)
HP-UX (Intel IA64)
HP-UX (PA-RISC)
RMAN
AIX (PowerPC)
Simple File Copy Within These
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
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Automatically fails over to previous backup
 Automated recovery through a previous point in time
recovery
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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
QUESTIONS
ANSWERS