Backup
Specifications
A backup is
a copy of data from your database that can be used to reconstruct that data.
The results of a backup created through RMAN can be either image copies or
backup sets.
When
performing a backup using RMAN, you can specify:
•
The
type of backup to be performed. You can perform backups of the entire database
to include every used data block in the files (a FULL backup) or incremental
backups (INCREMENTAL).
If CONFIGURE CONTROLFILE AUTOBACKUP is enabled, RMAN automatically backs up the control file and the current server parameter file after a BACKUP command is executed.
If CONFIGURE CONTROLFILE AUTOBACKUP is enabled, RMAN automatically backs up the control file and the current server parameter file after a BACKUP command is executed.
•
What
to backup. Valid values are DATABASE, DATAFILE, TABLESPACE, ARCHIVELOG, CURRENT
CONTROLFILE, or SPFILE.
•
Whether
an image copy (AS COPY) or backup set (AS BACKUPSET) is created
•
The
file name format and location for backup pieces (FORMAT)
•
Which
data files or archived redo logs should be excluded from the backup set (SKIP)
•
That
the input files should be deleted upon the successful creation of the backup
set (DELETE INPUT)
•
Proxy
options that specify how the Media Management Library (MML) is to carry out the
copying of the files. The PROXY option of the BACKUP command provides a way for
you to relieve RMAN of having to know how the media that is controlled by the
MML works.
Backup
Destinations
•
Backups
can be written to a designated disk directory, a Media Management Library, or
the Flash Recovery Area. Specifying a disk directory or the Flash Recovery Area
means that backups go to hard-disk media. Typically, they are regularly moved
offline to tape via the media management interface in order to maintain disk
space availability. Any disk directory can be specified as the destination of a
backup provided that it already exists.
•
If
you configure a Flash Recovery Area, many backup and recovery tasks are
simplified for you. The Oracle Database server automatically names files for
you, and deletes obsolete files when there is space pressure.
Configuring
Persistent Settings for RMAN
•
To
simplify ongoing use of RMAN for backup and recovery, RMAN enables you to set
several persistent configuration settings for each target database. These
settings control many aspects of RMAN’s behavior. You can save persistent
configuration information such as channel parameters, parallelism, and the
default device type in the RMAN repository (which is stored in either the
control file or a recovery catalog database).
•
These
settings have default values, which allow you to use RMAN immediately. However,
as you develop a more advanced backup and recovery strategy, you may have to
change these settings to implement that strategy. You can use the CONFIGURE
command to configure persistent settings for RMAN backup, restore, duplication,
and maintenance jobs. These settings are in effect for any RMAN session until
the configuration is cleared or changed.
Using
Enterprise Manager to Configure RMAN Settings
You can use
Oracle Enterprise Manager to specify the backup settings for an instance. From
the Database Home page, navigate to Availability > Backup Settings.
The Backup
Settings property page consists of three tabs:
•
Device: Used to set the disk and tape
configuration settings, including the Media Management Library (MML) settings
•
Backup
Set: Used to
specify parameters for backup sets and to enter host credentials
•
Policy: Used to set various backup and
retention policies before you initiate a backup, such as automatically backing
up the control file and SPFILE. The Policy page also allows you to configure
block change tracking support, a feature that provides faster incremental
backups.
Note: Backup settings provide the default
settings for all backups taken. When creating a backup, some of these settings
can be overridden for that specific backup.
