Transcript Compelling Reasons to us Oracle9i R2 RMAN

Session id 36487:
Compelling Reasons to Use
Oracle9i R2 RMAN
Wayne Linton
Oracle Database Administrator
Shell Canada Limited
Shell Canada Limited
Session: 36487
whoami
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Wayne Linton, I.S.P.
30+ years Shell Canada Limited
30+ year industry, 10+ years Oracle
OCP certified from 7.3 through 9i
past president Calgary Oracle Users Group
published in Select, Oracle magazines
part time Oracle DBA instructor at Southern
Alberta Institute of Technology
Shell Canada Limited
Session: 36487
Agenda
 brief introduction to server managed
backup/recovery and compelling reasons to
start using RMAN
 for users of 3rd Party backup tools, THE
compelling reason to switch to RMAN
 for pre-9i R2 users of RMAN, compelling
reasons to upgrade!
 9iR2 RMAN backup demo
 9iR2 RMAN block recovery demo
Shell Canada Limited
Session: 36487
RMAN at Shell Canada
Solaris 9203 (1)
Solaris 9203 (2)
Solaris
Solaris 817 (5)
NT4
817 (1)
AIX
817 (3)
AIX
817 (1)
816 (2)
AIX
817 (1)
816 (2)
sqlnet
staggered backup
schedules to
prevent deadlocks
9203 rdbms
RMAN
Catalog
9203
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Session: 36487
Backup for Recovery
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one day you WILL have to recover
do you know what backups are needed ?
do you know where they are located ?
are you certain that the backups are good ?
do you have all the required archive logs ?
 are your recovery skills a little rusty?
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Session: 36487
Shell Canada Limited
Session: 36487
A Matter of Trust ?
You Trust the Management
of your Data to Oracle ...
Why not Trust
the Management of your
Backup and Recovery to Oracle?
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Session: 36487
What Is RMAN?
 Recovery Manager
 Oracle utility to backup, restore, recover
databases from Oracle 8+
 invoked from command line or Enterprise
Manager GUI
 is aware of Oracle database internals
 tracks location of all backup files needed for
recovery (in controlfile or separate catalog)
 “server managed” backup and recovery
Shell Canada Limited
Session: 36487
RMAN - Server Managed
 RMAN uses Oracle-aware server processes
to perform backup and recovery operations
 fully integrated with database, fully supported
 knows what backups to take, have been
taken, and where they are located (cfile or
catalog)
 knows what backups are needed for recovery,
and restores the required backup files to the
right location automatically
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Session: 36487
RMAN Answers the Questions:
Which backups do I need?
Where are they?
Can I recover?
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Session: 36487
#1 Fully Integrated with Database
Fully Supported by Oracle
– aware of internals so can optimize for performance
• hot backup handling of fractured blocks
• skips backup of unused / unchanged blocks
– standby backups fully interchangeable with primary
(can offload backup load to standby machine!)
– can create clone and standby databases (duplicate
command)
– knows about RAC
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Session: 36487
#2 Supports Incremental Backups
– smaller backups and reduced backup/recovery time
– reads every block and checks for corruption
– multi-level incremental and cumulative backup
schemes possible
– backups to disk (faster restore) or tape directly
– can even do ‘cold’ (mounted) incremental backups!
Shell Canada Limited
Session: 36487
Incremental Backups
archivelogs
backup
time
changed block backup writes
space needed
 Time/space depends upon amount of change
db block read / corruption checking
% db block change
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Session: 36487
#3 Online Backups Simply &
Efficiently
– no need for begin-end backup commands
– fractured (changed) blocks re-read by RMAN during
online backups
– no additional redo generated
– multiple output streams (channels) in parallel
– multi-file read, block interleaving to one backupset
 current redo log switched, archived, and backed up
as part of backupset automatically
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Session: 36487
#4 Capture and Reporting of
Backup Metadata
– controlfile contains relevant RMAN backup
metadata (whether you use RMAN or not!)
– controlfile size governed by parameter
control_file_record_keep_time = #days
– LIST datafile, archivelog backup information
– REPORT unrecoverable, report obsolete, etc.
– recommended (but optional) use RMAN Catalog to
also store backup metadata for multiple databases
 backup will use controlfile if catalog not reachable
Shell Canada Limited
Session: 36487
3rd Party Users
 3rd party tools differ little from RMAN
 have nicer GUI than OEM ?
 BUT cost increases with size or number of
databases or servers where software used
 why pay a lot of money for functionality you
already have?
Shell Canada Limited
Session: 36487
#5 RMAN is FREE!!
– included in database license
– comes with Legato MML software to write to tape
– can purchase MML software from preferred third-party
media management vendor
– see http://otn.oracle.com/deploy/availability for
members of the Backup Solutions Program
Shell Canada Limited
Session: 36487
Pre-9i users of RMAN
 early versions of RMAN were somewhat
awkward to use
 verbose scripting and messages
 lacking in ‘basic’ functionality like deletion of
obsolete O/S backup files
 9i and 9iR2 have significantly improved
usability and functionality
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Session: 36487
#6 Persistent Configuration
Parameters
– RMAN remembers backup settings from one session
to another (in controlfile, catalog), making routine
backups as simple as …
BACKUP DATABASE;
– set once and forget about them
– can configure many parameters ...
Shell Canada Limited
Session: 36487
8i vs 9i RMAN Backup Script
run {
allocate channel d1 type disk;
allocate channel d2 type disk;
allocate channel d3 type disk;
sql "alter system switch logfile";
backup
incremental level 0
format '$HOME/BACKUP/%d_%t_%s_%p.bus'
filesperset 5 (database include current controlfile);
sql "alter system archive log current";
backup
format '$HOME/BACKUP/%d_%t_%s_%p.bus'
(archivelog all delete input);
backup
format '$HOME/BACKUP/%d_%t_%s_%p.bus'
(current controlfile);
release channel d1;
release channel d2;
release channel d3;
}
backup database
incremental level 0
plus archivelog delete all input;
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Session: 36487
#6a Configure Retention Policy
– by backup redundancy count or number of days
recovery window, will determine how many backups to
keep for how long
CONFIGURE RETENTION POLICY …
– then the obsolete OS backup files are physically
removed by the command:
DELETE OBSOLETE;
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Session: 36487
#6b Auto Channel Allocation &
Parallelism
– channels are allocated automatically
– no need to code each channel separately
– number of channels allocated specified with
parallelism parameter
CONFIGURE DEVICE TYPE DISK PARALLELISM 2;
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Session: 36487
#6c Controlfile, SPFILE Auto Backup
– if set to ON, controlfile and spfile backed up together
in separate backup piece with every backup
CONFIGURE CONTROLFILE AUTOBACKUP ON;
– controlfile and spfile always and automatically backed
up with datafile #1 (system) if autobackup set to OFF
– note that spfile automatically backed up, NOT pfile!
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Session: 36487
#6c Controlfile, SPFILE Auto Backup
cont’d ...
– if set to ON, controlfile and spfile backed up
automatically whenever the database structure is
changed
– new, dropped, offlined, onlined tablespace, datafile,
redo logs, renamed file, etc.
– no need to invoke RMAN for this to happen
– auto-backup event noted in the alert log
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Session: 36487
#6d Other Noteworthy Parameters
– skip read-only tablespaces already backed-up with
CONFIGURE BACKUP OPTIMIZATION ON;
– exclude specific tablespaces with
CONFIGURE EXCLUDE FOR TABLESPACE xxxxxx;
– create up to 4 backup copies with
CONFIGURE BACKUP COPIES TO n;
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Session: 36487
#7 Auto Archive and Backup
Current Redo
– no need to manually switch, backup current log
– one copy of all archived logs backed up, current log
switched, archived, and then also backed up
– guaranteed to save all requisite redo for recovery
BACKUP DATABASE PLUS ARCHIVELOG;
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Session: 36487
#8 Clearing Multiple Archivelog
Destinations
– pre-9i supported clearing only 1 archivelog
destination
– multiple archivelog destinations searched if
necessary to obtain good log copy for backup
– all archivelog destinations cleared after backup with
command:
BACKUP DATABASE PLUS ARCHIVELOG
DELETE ALL INPUT;
Shell Canada Limited
Session: 36487
#9 Less Verbose Runtime
Messages
– every line of pre-9i RMAN output was prefixed with
RMAN-xxxxx, plus additional less useful
informational messages obscured the ‘good stuff’
– these can be optionally turned on, but are supressed
by default
– errors will still be prefixed with RMAN-xxxxx
– scan the log for RMAN-00569
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Session: 36487
D E M O N S T R A T I O N
RMAN Incremental
Backup
… in progress
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Session: 36487
Demonstration
 show all; (persistent configuration parameters)
 level 2 incremental backup:
backup incremental level 2
database plus archivelog
delete all input;
 list backup of tablespace WAIN;
 report unrecoverable;
 delete obsolete;
Shell Canada Limited
Session: 36487
#10
Block Media Recovery
– no need to offline and restore large datafile when only
a few blocks are corrupted
– backup / validate places location of corrupted
database blocks in view:
v$database_block_corruption
– alert log also lists corrupted file#, block#
BLOCKRECOVER CORRUPTION LIST;
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Session: 36487
D E M O N S T R A T I O N
RMAN
blockrecover
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Session: 36487
Demonstration
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report unrecoverable;
select * from v$database_block_corruption;
corrupt tablespace wain datafile
backup validate check logical tablespace wain;
select * from v$database_block _corruption;
blockrecover corruption list;
backup validate check logical tablespace wain;
select * from v$database_block _corruption;
Shell Canada Limited
Session: 36487
#11 Restartable Backups and
Restores
BACKUP DATABASE
NOT BACKED UP SINCE TIME …
– Restore failures may leave good versions of some
datafiles in the right place
– restarted restore will NOT restore those files
– can force them to be restored anyway with:
RESTORE FORCE ...
Shell Canada Limited
Session: 36487
#12 Staging of Archivelogs During
Recovery
– sometimes you don’t have enough disk space to
restore all the archived redo logs required for recovery
(in this example, only 100M)
– new feature automatically ‘stages’ restore of archived
logs as per available disk, applies them, and deletes
them to make room for next set of logs
RECOVER DATABASE
DELETE ARCHIVELOG MAXSIZE 100M … ;
Shell Canada Limited
Session: 36487
#13
Backing Up Backupsets
– backupsets can reside on disk for faster restore
– older backupsets can be backed up to tape and
deleted automatically from disk to make room for
new backups on disk
– backupset backups are also checked for corruption
BACKUP BACKUPSET … CREATED BEFORE …
DELETE INPUT;
Shell Canada Limited
Session: 36487
#14 Other Important RMAN
Functions
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recover to previous ‘incarnations’ if using catalog
automatic ‘tagging’ of backups
DBNEWID to change id of ‘manually’ cloned DB
OEM GUI wizard improvements
‘automated’ TSPITR for self-contained tablespaces
DUPLICATE command to build clone and standby
databases
 BACKUP and RESTORE VALIDATE
Shell Canada Limited
Session: 36487
My Personal Favourites
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Configure Retention Policy (Delete Obsolete!)
Configure Controlfile Autobackup
Other Persistent Configuration Parameters!!!!!
Block Media Recovery while still Online!
Backup Database Plus Archivelog
Delete All Input
 Recover Database Delete Archivelog Maxsize
 Restartable Backups and Restores
Shell Canada Limited
Session: 36487
Upon The Shoulders of ...
 Tammy Bednar, Oracle Corporation Database
Backup & Recovery Strategies and Best
Practices - paper 213, OOW 2001
 Tammy Bednar, Oracle Corporation
Rich Bernat, Chevrontexaco Corporation
Are You Using the Best Solution for
Protecting Your Enterprise? - paper 32513,
OOW 2002
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Session: 36487
Upon The Shoulders of ...
 Dave Anderson, SkillBuilders, Inc.
A Practical Introduction to Oracle9i RMAN
Oratechs, 2003
Shell Canada Limited
Session: 36487
Next Steps….
 Recommended sessions
– 40104 RMAN 10g: Reloaded - Tammy Bednar
Tues. 9th, 3:30 PM Moscone Room 304
– 36675 RMAN 10g & ATA Storage in Action - Bob Ng
Weds. 10th, 8:30 AM (not sure which room)
 Recommended hands-on labs
– Manage the Database Environment, Lesson 6
Performing Backups and Recovering Your Database
 Demogrounds
– 10g RMAN (many!) New Features, new EM interface
Shell Canada Limited
Session: 36487
Next Steps….
 Relevant web sites to visit for more information
– Metalink - many technical notes, articles, papers
– OTN & Oracle Documentation
• Oracle9i Recovery Manager User’s Guide - A96566-01
• Oracle9i Recovery Manager Reference - A96565-01
• Oracle9i Recovery Manager Quick Reference - A96564-01
– Oracle9i RMAN Backup and Recovery,
Freeman & Hart, ISBN 0-07-222662-5
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Session: 36487
Reminder –
please complete the
OracleWorld online session
survey
Thank you.
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Session: 36487
QUESTIONS
ANSWERS
Shell Canada Limited
Session: 36487
Session id 36487:
Compelling Reasons to Use
Oracle9i R2 RMAN
Wayne Linton
Oracle Database Administrator
Shell Canada Limited
[email protected]
Shell Canada Limited
Session: 36487