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• Backupsets are comprised of one or more backup pieces, which are physical files containing the used blocks from the target database. Backup is done at the block level and the unused blocks are not backed up by RMAN. Backup pieces can contain datafiles and archivelogs.
  Backupsets can also be Full or Incremental. Incremental backups consist only of blocks that have been modified since another incremental backup of an equal or lower level. Full backups are the same as an Incremental Level 0 backup, only full backupsets cannot be used as the base backup for an Incremental backup strategy.


• Image Copies, on the other hand are more like full file copies of the datafiles that are being backed up.

• If your database is running in NOARCHIVELOG mode, the database cannot be open during the backup.


• If running in ARCHIVELOG mode, the frequency of your backups may depend on how long it takes to restore/recover, how much space you have for your archivelogs and what kind of backup path (full or incremental) you adopt.


• RMAN needs a Media Management Layer (like Legato Storage Manager) to perform backups directy to tape.

[prod-server:oracle] $ rman target sys/yoursyspwd rcvcat rman_admin/rman@rcat

Recovery Manager: Release 9.0.1.0.0 - Production

(c) Copyright 2001 Oracle Corporation.  All rights reserved.

connected to target database: DEMO (DBID=3191250744)
connected to recovery catalog database

RMAN> create script prod_full_backup {
2> allocate channel ch1 type disk;
3> backup full database include current controlfile
4> tag prod_full_backup
5> format '/u03/backup/%d_t%t_s%s_p%p';
6> release channel ch1;
7> }

created script prod_full_backup

RMAN>

RMAN> delete script prod_full_backup;

deleted script: prod_full_backup

RMAN> replace script prod_full_backup {
2> allocate channel ch1 type disk;
3> backup full database include current controlfile
4> tag prod_full_backup
5> format '/u03/backup/prod_t%t_s%s_p%p';
6> sql "alter system archive log current";
7> backup archivelog from logseq=16 thread 1 delete input
8> format '/u03/backup/prodarch_t%t';
9> release channel ch1;
10> }

replaced script prod_full_backup

RMAN>

SQL> select * from rc_stored_script;

    DB_KEY DB_NAME  SCRIPT_NAME
---------- -------- ------------------------------
         1 PROD     prod_full_backup

SQL> select text from rc_stored_script_line where script_name='prod_full_backup';

TEXT
-------------------------------------------------
 {
allocate channel ch1 type disk;
backup full database include current controlfile
tag prod_full_backup
format '/u03/backup/prod_t%t_s%s_p%p';
sql "alter system archive log current";
backup archivelog from logseq=16 thread 1 delete input
format '/u03/backup/prodarch_t%t';
release channel ch1;
}

10 rows selected.

RMAN> run {execute script prod_full_backup;}

executing script: prod_full_backup

allocated channel: ch1
channel ch1: sid=9 devtype=DISK

Starting backup at 13-DEC-01
channel ch1: starting full datafile backupset
channel ch1: specifying datafile(s) in backupset
including current controlfile in backupset
input datafile fno=00001 name=/u02/oradata/prod/system01.dbf
input datafile fno=00002 name=/u02/oradata/prod/undotbs01.dbf
input datafile fno=00004 name=/u02/oradata/prod/example01.dbf
input datafile fno=00005 name=/u02/oradata/prod/indx01.dbf
input datafile fno=00007 name=/u02/oradata/prod/users01.dbf
input datafile fno=00003 name=/u02/oradata/prod/drsys01.dbf
input datafile fno=00006 name=/u02/oradata/prod/tools01.dbf
input datafile fno=00008 name=/u02/oradata/prod/oem_rep.dbf
channel ch1: starting piece 1 at 13-DEC-01
channel ch1: finished piece 1 at 13-DEC-01
piece handle=/u03/backup/prod_t448394435_s2_p1 comment=NONE
channel ch1: backup set complete, elapsed time: 00:03:06
Finished backup at 13-DEC-01

sql statement: alter system archive log current

Starting backup at 13-DEC-01
current log archived
channel ch1: starting archive log backupset
channel ch1: specifying archive log(s) in backup set
input archive log thread=1 sequence=16 recid=3 stamp=448308565
input archive log thread=1 sequence=17 recid=4 stamp=448393893
input archive log thread=1 sequence=18 recid=5 stamp=448393895
input archive log thread=1 sequence=19 recid=6 stamp=448394623
input archive log thread=1 sequence=20 recid=7 stamp=448394625
channel ch1: starting piece 1 at 13-DEC-01
channel ch1: finished piece 1 at 13-DEC-01
piece handle=/u03/backup/prodarch_t448394628 comment=NONE
channel ch1: backup set complete, elapsed time: 00:00:35
channel ch1: deleting archive log(s)
archive log filename=/u01/app/oracle/oradata/prod/archive/prod1_16.arc recid=3 stamp=448308565
archive log filename=/u01/app/oracle/oradata/prod/archive/prod1_17.arc recid=4 stamp=448393893
archive log filename=/u01/app/oracle/oradata/prod/archive/prod1_18.arc recid=5 stamp=448393895
archive log filename=/u01/app/oracle/oradata/prod/archive/prod1_19.arc recid=6 stamp=448394623
archive log filename=/u01/app/oracle/oradata/prod/archive/prod1_20.arc recid=7 stamp=448394625
Finished backup at 13-DEC-01

released channel: ch1

RMAN>

#!/bin/ksh
# Shell script to run RMAN script prod_full_backup.rcv
# Logging messages to prod_full_backup.log

# Set environment variables
export ORACLE_SID=prod
export ORACLE_HOME=/u01/app/oracle/product/9.0.1

# Connect to RMAN and run the backup script
rman target sys/yoursyspwd rcvcat rman_admin/rman@rcat 
cmdfile /export/home/oracle/scripts/prod_full_backup.rcv 
msglog /export/home/oracle/log/full_backup.log
exit

[prod-server:oracle] $ chmod 755 rman_backup.ksh

run {execute script prod_full_backup;}

[prod-server:oracle] $ crontab -e
00 21 * * 0 $HOME/scripts/rman_backup.ksh

• The level 1 incremental will back up all blocks that have changed in the last 2 weeks


• The level 2 incremental will back up all blocks that changed since the last week


• The level 3 incremental will back up all blocks that changed since yesterday