ORACLE RMAN BACKUP

This article shows how to setup and configure RMAN backups.

A. ENABLING ARCHIVELOG MODE
When you enable ARCHI!"#$ Mode% you will pre&ent R!'# logs to be o&erwritten.
To enable archi&ing let(s first check the current archi&ing )ode*
+,"- +!"!CT "#$.M#'! /R#M +0+.1'ATA2A+!3
"#$.M#'!
444444444444
N#ARCHI!"#$
After ensuring that we are on N#ARCHI!"#$ )ode% we can enable archi&ing*
+,"- startup )ount
#RAC"! instance started.
Total +yste) $lobal Area 567879:;< bytes
/i=ed +i>e 5:??9@6 bytes
ariable +i>e 58;6@?76? bytes
'atabase 2uffers @85<86@7 bytes
Redo 2uffers @<@577 bytes
'atabase )ounted.
+,"- alter database archi&elog3
'atabase altered.
+,"- alter database open3
'atabase altered.
After opening database% let(s check if we were successful*
B. SCHEDULING RMAN BACKUP
a. RMAN SCHEDULING VIA ORACLE ENTERPRISE MANAGER (OEM)
In order to schedule RMAN backup &ia oracle enterprise )anager% you need to login to #!M
successfully with your +0+ account. After loging in% na&igate to AMaintenance4- +chedule
2ackupB.
To perfor) successful backup% you need to infor) #racle about your operating syste)
login credentials because #racle will need to access database files through your os file
security syste).
ATTENTION: When you change your operating syste) password% do not forget to update
your #+ credentials info on #!M pre&iously scheduled RMAN Cobs.
"ater on% choose Acusto)i>ed backupD to specify your backup strategy and choose Awhole
databaseD as the obCect you want to backup unless you ha&e another specific purpose.
Now you will see the page which will allow you to sa&e all the details you want your RMAN
backup schedule has.
"ets e=plore these properties in details one by one*
Backup Type: There are two types of backups strategi>es you can choose which are full
backups and incre)ental backups. We will go in )ore details on incre)ental backups
because it has a a)a>ing algorith) inside.
!u"" Backup#
4 I$c%e&e$'a" Backup#: RMAN incre)ental backups back up only datafile blocks that
ha&e changed since a specified pre&ious backup. 0ou can )ake incre)ental backups of
databases% indi&idual tablespaces or datafiles. The goal of an incre)ental backup is to back
up only those data blocks that ha&e changed since a pre&ious backup.
I$c%e&e$'a" Backup A"()%*'+&: !ach data block in a datafile contains a syste) change
nu)ber E+CNF% which is the +CN at which the )ost recent change was )ade to the block.
'uring an incre)ental backup% RMAN reads the +CN of each data block in the input file
and co)pares it to the checkpoint +CN of the parent incre)ental backup. If the +CN in the
input data block is greater than or eGual to the checkpoint +CN of the parent% then RMAN
copies the block. Note that if you enable the block change tracking feature% RMAN can refer
to the change tracking file to identify changed blocks in datafiles without scanning the full
contents of the datafile. #nce enabled% block change tracking does not alter how you take
or use incre)ental backups% other than offering increased perfor)ance. Incre)ental
backups either be "e&el ? Esa)e as full back upF or "e&el 5 Edetails are belowF.
D*,,e%e$'*a" )% Cu&u"a'*-e Le-e". I$c%e&e$'a" Backup#:
H A differential backup% which backs up all blocks changed after the )ost recent
incre)ental backup at le&el 5 or ?.
H A cu)ulati&e backup% which backs up all blocks changed after the )ost recent
incre)ental backup at le&el ?.
Incre)ental backups are differential by default.
HINT: Cu)ulati&e backups are preferable to differential backups when reco&ery ti)e is
)ore i)portant than disk space% because during reco&ery each differential backup )ust be
applied in succession. Ise cu)ulati&e incre)ental backups instead of differential% if
enough disk space is a&ailable to store cu)ulati&e incre)ental backups.
H Backup M)/e: If your database is in ARCHI!"#$ )ode% you can take #N"IN! backups
which )eans you can ha&e your in #J!N )ode during backup. #n the other hand% if your
database is in N#ARCHI!"#$ )ode% when your backup Cob starts it will shutdown your
database and start up your database in )ount state. After finishing backup procedure%
your backup Cob will alter your database to open state.
0 A/-a$ce/: If you )ark AAlso backup all archi&ed logs on diskD option% r)an will backup
your achi&ed logs. If you also )ark A'elete all archi&ed logs fro) disk after successfully
backing upD r)an will delete the) after backing up. This option is useful when you start to
ha&e disk si>e proble)s. Marking AIse Jro=y copy supported by )edia )anage)ent
software to perfor) a backupD will let you enable RMAN turns o&er control of the data
transfer to a )edia )anager that supports this feature. When you )ark A'elete obsolete
backupsD option% the retention policy deter)ines which backups and i)age copies are
obsolete. If selected% the obsolete backups and copies will be deleted when the backup is
finished.
When you click N!KT button% you will see a screen which will ask you about where would
you like to store your backup files% you can either choose disk backup or tape backup*
Third step is setting the Cob schedule*
"ater on% fourth step is checking the RMAN script and sub)itting the Cob*
1. RMAN SCHEDULING VIA RMAN SCRIPTING
If you no longer ha&e a particular archi&elog file you can let RMAN catalog
know this by issuing the following co))and at the r)an pro)pt after
connecting to the r)an catalog and the target database 4
change archi&elog all crosscheck 3
C. R!+T#RIN$LR!C#!RIN$ /R#M RMAN 2ACMIJ
a. Connecting to RMAN
After connecting to RMAN co))and pro)pt% we can set retention policy to reco&ery
window% redundancy and controlfile autobackup on options as below*
SOURCE
5. !nabling ARCHI!"#$ Mode% http*LLwww.cuddletech.co)LarticlesLoracleLnode86.ht)l
@. #racleN 'atabase 2ackup and Reco&ery 2asics% http*LLdownload4
uk.oracle.co)LdocsLcdL259:?<.?5Lbackup.5?@Lb5759@Lbkup??7.ht)
ORACLE RMAN BACKUP
This article shows how to setup and configure RMAN backups.
A. ENABLING ARCHIVELOG MODE
When you enable ARCHI!"#$ Mode% you will pre&ent R!'# logs to be o&erwritten.
To enable archi&ing let(s first check the current archi&ing )ode*
+,"- +!"!CT "#$.M#'! /R#M +0+.1'ATA2A+!3
"#$.M#'!
444444444444
N#ARCHI!"#$
After ensuring that we are on N#ARCHI!"#$ )ode% we can enable archi&ing*
+,"- startup )ount
#RAC"! instance started.
Total +yste) $lobal Area 567879:;< bytes
/i=ed +i>e 5:??9@6 bytes
ariable +i>e 58;6@?76? bytes
'atabase 2uffers @85<86@7 bytes
Redo 2uffers @<@577 bytes
'atabase )ounted.
+,"- alter database archi&elog3
'atabase altered.
+,"- alter database open3
'atabase altered.
After opening database% let(s check if we were successful*
B. SCHEDULING RMAN BACKUP
a. RMAN SCHEDULING VIA ORACLE ENTERPRISE MANAGER (OEM)
In order to schedule RMAN backup &ia oracle enterprise )anager% you need to login to #!M
successfully with your +0+ account. After loging in% na&igate to AMaintenance4- +chedule
2ackupB.
To perfor) successful backup% you need to infor) #racle about your operating syste)
login credentials because #racle will need to access database files through your os file
security syste).
ATTENTION: When you change your operating syste) password% do not forget to update
your #+ credentials info on #!M pre&iously scheduled RMAN Cobs.
"ater on% choose Acusto)i>ed backupD to specify your backup strategy and choose Awhole
databaseD as the obCect you want to backup unless you ha&e another specific purpose.
Now you will see the page which will allow you to sa&e all the details you want your RMAN
backup schedule has.
"ets e=plore these properties in details one by one*
Backup Type: There are two types of backups strategi>es you can choose which are full
backups and incre)ental backups. We will go in )ore details on incre)ental backups
because it has a a)a>ing algorith) inside.
!u"" Backup#
4 I$c%e&e$'a" Backup#: RMAN incre)ental backups back up only datafile blocks that
ha&e changed since a specified pre&ious backup. 0ou can )ake incre)ental backups of
databases% indi&idual tablespaces or datafiles. The goal of an incre)ental backup is to back
up only those data blocks that ha&e changed since a pre&ious backup.
I$c%e&e$'a" Backup A"()%*'+&: !ach data block in a datafile contains a syste) change
nu)ber E+CNF% which is the +CN at which the )ost recent change was )ade to the block.
'uring an incre)ental backup% RMAN reads the +CN of each data block in the input file
and co)pares it to the checkpoint +CN of the parent incre)ental backup. If the +CN in the
input data block is greater than or eGual to the checkpoint +CN of the parent% then RMAN
copies the block. Note that if you enable the block change tracking feature% RMAN can refer
to the change tracking file to identify changed blocks in datafiles without scanning the full
contents of the datafile. #nce enabled% block change tracking does not alter how you take
or use incre)ental backups% other than offering increased perfor)ance. Incre)ental
backups either be "e&el ? Esa)e as full back upF or "e&el 5 Edetails are belowF.
D*,,e%e$'*a" )% Cu&u"a'*-e Le-e". I$c%e&e$'a" Backup#:
H A differential backup% which backs up all blocks changed after the )ost recent
incre)ental backup at le&el 5 or ?.
H A cu)ulati&e backup% which backs up all blocks changed after the )ost recent
incre)ental backup at le&el ?.
Incre)ental backups are differential by default.
HINT: Cu)ulati&e backups are preferable to differential backups when reco&ery ti)e is
)ore i)portant than disk space% because during reco&ery each differential backup )ust be
applied in succession. Ise cu)ulati&e incre)ental backups instead of differential% if
enough disk space is a&ailable to store cu)ulati&e incre)ental backups.
H Backup M)/e: If your database is in ARCHI!"#$ )ode% you can take #N"IN! backups
which )eans you can ha&e your in #J!N )ode during backup. #n the other hand% if your
database is in N#ARCHI!"#$ )ode% when your backup Cob starts it will shutdown your
database and start up your database in )ount state. After finishing backup procedure%
your backup Cob will alter your database to open state.
0 A/-a$ce/: If you )ark AAlso backup all archi&ed logs on diskD option% r)an will backup
your achi&ed logs. If you also )ark A'elete all archi&ed logs fro) disk after successfully
backing upD r)an will delete the) after backing up. This option is useful when you start to
ha&e disk si>e proble)s. Marking AIse Jro=y copy supported by )edia )anage)ent
software to perfor) a backupD will let you enable RMAN turns o&er control of the data
transfer to a )edia )anager that supports this feature. When you )ark A'elete obsolete
backupsD option% the retention policy deter)ines which backups and i)age copies are
obsolete. If selected% the obsolete backups and copies will be deleted when the backup is
finished.
When you click N!KT button% you will see a screen which will ask you about where would
you like to store your backup files% you can either choose disk backup or tape backup*
Third step is setting the Cob schedule*
"ater on% fourth step is checking the RMAN script and sub)itting the Cob*
1. RMAN SCHEDULING VIA RMAN SCRIPTING
If you no longer ha&e a particular archi&elog file you can let RMAN catalog
know this by issuing the following co))and at the r)an pro)pt after
connecting to the r)an catalog and the target database 4
change archi&elog all crosscheck 3
C. R!+T#RIN$LR!C#!RIN$ /R#M RMAN 2ACMIJ
a. Connecting to RMAN
After connecting to RMAN co))and pro)pt% we can set retention policy to reco&ery
window% redundancy and controlfile autobackup on options as below*
SOURCE
5. !nabling ARCHI!"#$ Mode% http*LLwww.cuddletech.co)LarticlesLoracleLnode86.ht)l
@. #racleN 'atabase 2ackup and Reco&ery 2asics% http*LLdownload4
uk.oracle.co)LdocsLcdL259:?<.?5Lbackup.5?@Lb5759@Lbkup??7.ht)