what files does rman backup

The RMAN BACKUP command supports backing up the following types of files:

• Data files and control files
• Server parameter file
• Archived redo logs
• RMAN backups

Full Answer

How to configure RMAN backup?

To configure backup optimization:

• Start RMAN and connect to a target database and a recovery catalog (if used).
• Run the SHOW BACKUP OPTIMIZATION command to determine whether optimization is currently enabled. ...
• Enable backup optimization by running the following command: CONFIGURE BACKUP OPTIMIZATION ON;

Is Symantec backup a substitute for RMAN?

Symantec NetBackup to backup the Oracle Database Appliance using Oracle StorageTek tape products. The information in this document is intended to detail basic configuration of NetBackup (NBU) on the Oracle Database Appliance to allow for RMAN backups directly to tape. A restore example, private

How to improve RMAN backup performance?

• Do you have any tablespaces that are in/can be placed into READ-ONLY mode? ...
• Are you using BIGFILE tablespaces? If so, you can parallelize the backup using the SECTION SIZE clause.
• You could consider the merged incremental backup strategy. ...

How to take offline backups using RMAN?

• Run BACKUP CURRENT CONTROLFILE.
• Include a backup of the control file within any backup by using the INCLUDE CURRENT CONTROLFILE option of the BACKUP command.
• Back up datafile 1, because RMAN automatically includes the control file and SPFILE in backups of datafile 1 when the controlfile autobackup is set to OFF.

Where are RMAN backup files?

RMAN> BACKUP AS BACKUPSET DATABASE PLUS ARCHIVELOG; You can also take a backup of only a specific table space. The following example takes backup of only PRD01 tablespace. Once the backup is completed, do an ls on the /backup/rman directory, you'll now see RMAN backup files.

What are RMAN files?

Oracle RMAN stores data in image files or backup sets, which are made up of backup pieces. A backup piece is an RMAN-specific binary file that only RMAN can create or restore.

Which parameter file is backed up by Oracle RMAN tool?

RMAN uses a snapshot control file to ensure a read-consistent version. If CONFIGURE CONTROLFILE AUTOBACKUP is ON (by default it is OFF ), then RMAN automatically backs up the control file and server parameter file after every backup and after database structural changes.

Does RMAN backup empty blocks?

In Oracle 10g Release 2 RMAN does not backup unused blocks (empty blocks below the High watermark). Further related information; Null Compression: When backing up datafiles into backup sets, RMAN does not back up the contents of data blocks that have never been allocated.

What is the difference between RMAN and export backup?

Export is often used as a supplement to RMAN, usually for the restore of specific tables. Recovery manager (rman) - RMAN is designed for backup and recovery, a extension of the Enterprise Backup Utility (EBU). RMAN takes full, physical, consistent backups of your database files..

Where is RMAN information stored?

The RMAN repository is the collection of metadata about the target databases that RMAN uses for backup, recovery, and maintenance. RMAN always stores this information in records in the control file. The version of this information in the control file is the authoritative record of RMAN's backups of your database.

Which file is not backup by RMAN?

Although the database depends on other types of files for operation, such as network configuration files, password files, and the contents of the Oracle home, these files cannot be backed up with RMAN.

What are the files containing in the full database backup?

Overview of File Backups. A full file backup backs up all the data in one or more files or filegroups. By default, file backups contain enough log records to roll forward the file to the end of the backup operation. Backing up a read-only file or filegroup is the same for every recovery model.

How do I backup my RMAN database?

Backing Up a Database in ARCHIVELOG ModeStart RMAN and connect to a target database.Run the BACKUP DATABASE command. For example, enter the following command at the RMAN prompt to back up the database and all archived redo log files to the default backup device: RMAN> BACKUP DATABASE PLUS ARCHIVELOG;

What are the 3 types of backups?

The most common backup types are a full backup, incremental backup and differential backup. Other backup types include synthetic full backups and mirroring.

Can you take image backups using RMAN?

Although image copies cannot use all RMAN features, their advantages are that you can apply incremental backups to them (synthetic full backups) and you can use them directly in place without first copying them, for very fast restores. Each backup set contains one or more physical files called backup pieces.

What is compressed backup in RMAN?

The AS COMPRESSED BACKUPSET option of the BACKUP command allows RMAN to perform binary compression of backupsets. The resulting backupsets do not need to be uncompressed during recovery. It is most useful in the following circumstances: You are performing disk-based backup with limited disk space.

Why does RMAN always choose incremental backups over archived redo logs?

If it has a choice, then RMAN always chooses incremental backups over archived redo logs because applying changes at a block level is faster than applying redo.

What does RMAN do when it is unused?

When employing unused block compression, RMAN skips reading, and backing up, any database blocks that are not currently allocated to some database object. This is regardless of whether those blocks had previously been allocated.

What is the first channel allocated during a backup job?

The first channel allocated during the backup job creates the autobackup and places it into its own backup set. For autobackups after database structural changes, the server process associated with the structural change makes the backup.

What is sparse backup?

A sparse backup can either be in the backup set format (default) or the image copy format. RMAN restores sparse data files from sparse backups and then recovers them from archive and redo logs. You can perform a complete or a point-in-time recovery on sparse data files.

What is RMAN multiplexing?

For example, the FILESPERSET parameter of the BACKUP command determines how many data files to put in each backup set . The MAXOPENFILES parameter of ALLOCATE CHANNEL or CONFIGURE CHANNEL defines how many data files RMAN can read from simultaneously. The basic multiplexing algorithm is as follows:

What is proxy copy in RMAN?

During a proxy copy, RMAN turns over control of the data transfer to a media manager that supports this feature. Proxy copy can only be used with media managers that support it and cannot be used with channels of type DISK. The PROXY option of the BACKUP command specifies that a backup is a proxy copy.

What is the backup copy of command?

You can use the BACKUP COPY OF command to back up existing image copies of database files either as backup sets or as image copies. When using this command, an image copy of every data file specified in the command must exist. If there are multiple copies of a data file, then the latest one is used.

What is a backup set in RMAN?

RMAN can store backup data in a logical structure called a backup set, which is the smallest unit of an RMAN backup. A backup set contains the data from one or more datafiles, archived redo logs, control files, or server parameter file. Backup sets, which are only created and accessed through RMAN, are the only form in which RMAN can write backups to media managers such as tape drives and tape libraries.

Why does RMAN always choose incremental backups over archived redo logs?

If it has a choice, then RMAN always chooses incremental backups over archived redo logs because applying changes at a block level is faster than applying redo.

What is proxy copy in RMAN?

During a proxy copy, RMAN turns over control of the data transfer to a media manager that supports this feature. Proxy copy can only be used with media managers that support it and cannot be used with channels of type DISK. The PROXY option of the BACKUP command specifies that a backup should be a proxy copy.

What is RMAN encryption?

RMAN supports backup encryption for backup sets. You can use wallet-based transparent encryption, password-based encryption, or both. You can use the CONFIGURE ENCRYPTION command to configure persistent transparent encryption. Use the SET ENCRYPTION command at the RMAN session level to specify password-based encryption.

Why is RMAN status obsolete?

For example, if a database backup is considered OBSOLETE in the RMAN repository, it is because it is either not needed for recovery to a point within the recovery window, or it is redundant.

What is inconsistent backup?

Any database backup that is not consistent is an inconsistent backup. A backup made when the database is open is inconsistent, as is a backup made after an instance failure or SHUTDOWN ABORT command. When a database is restored from an inconsistent backup, Oracle Database must perform media recovery before the database can be opened, applying any pending changes from the redo logs.

Does RMAN backup undo?

In backup undo optimization, RMAN excludes undo not needed for recovery of a backup, that is, for transactions that have been committed. Backup undo optimization works for level 0 and full disk backups and Oracle Secure Backup (OSB) tape backups. Unlike backup optimization, backup undo optimization is not configurable.

What is Oracle RMAN?

This chapter describes backup strategies using Oracle Recovery Manager utility (RMAN) with Data Guard and standby databases. RMAN can perform backups with minimal effect on the primary database and quickly recover from the loss of individual datafiles, or the entire database. RMAN and Data Guard can be used together to simplify the administration of a Data Guard configuration.

What to do if you lose all control files?

If you lose all of your control files, you can choose among the following procedures, depending on the amount of downtime that is acceptable. Create a new control file If all control file copies are lost, you can create a new control file using the NORESETLOGS option and open the database after doing media recovery.

Can a standby database share backup files?

The following sections describe how to modify the backup procedures for other configurations, such as when the standby and primary databases cannot share backup files ; the standby instance is only used to remotely archive redo log files; or the standby database filenames are different than the primary database.

Can you backup redo logs on standby?

In a standby environment, backing up datafiles and archived redo log files taken on the primary or standby system are usable on either system for recovery. Although some files such as the control file and SPFILE must be backed up on the primary database, the process of backing up datafiles and archived redo log files can be off-loaded to the standby system, to minimize the effect of backups on the production system.

Can RMAN run against FAL?

Use the same procedure described in Section 10.1, with the exception that the RMAN commands that back up database files cannot be run against the FAL server. The FAL server can be used as a backup source for all archived redo log files, thus off-loading backups of archived redo log files to the FAL server.

What is RMAN backup and recovery environment?

The RMAN backup and recovery environment is preconfigured for each target database. The configuration is persistent and applies to all subsequent operations on this target database, even if you exit and restart RMAN.

What is a RMAN file?

RMAN supports the use of command files to manage recurring tasks such as weekly backups. A command file is a client-side text file containing RMAN commands, exactly as you enter them at the RMAN prompt. You can use any file extension. The RUN command provides a degree of flow-of-control in your scripts.

What is crosscheck in RMAN?

The CROSSCHECK command synchronizes the logical records of RMAN backups and copies with the files on storage media. If a backup is on disk, then CROSSCHECK determines whether the header of the file is valid. If a backup is on tape, then RMAN queries the RMAN repository for the names and locations of the backup pieces. It is a good idea to crosscheck backups and copies before deleting them.

What does "delete" mean in RMAN?

The DELETE command removes RMAN backups and copies from disk and tape, updates the status of the files to DELETED in the control file repository, and removes the records from the recovery catalog (if you use a catalog). If you run RMAN interactively, and if you do not specify the NOPROMPT option, then DELETE displays a list of files and prompts for confirmation before deleting any file in the list.

What command is used to verify that all database files exist?

You can use the VALIDATE command to confirm that all database files exist, are in their correct location, and are free of physical corruption. The CHECK LOGICAL option also checks for logical block corruption.

Is incremental backup faster than redo logs?

Incremental backups are generally smaller and faster to make than full database backups. Recovery with incremental backups is faster than using redo logs alone. The starting point for an incremental backup strategy is a level 0 incremental backup, which backs up all blocks in the database.

Does RMAN overwrite old records?

The database may overwrite older records in the control file, but RMAN maintains records forever in the catalog unless the records are deleted by the user . This chapter explains how to use RMAN in the most basic configuration, which is without a recovery catalog or media manager.

Can you assign a tag to a particular backup?

If you are taking lot of backups, it will be easier to assign a tag to a particular backup, which we’ll later use during Oracle recovery (or while using list command to view it).

Can you take a backup of an Oracle database if you are not a DBA?

by Ramesh Natarajan on August 27, 2013. Tweet. Even if you are not an Oracle DBA, you’ll still encounter a situation where you may have to take a backup of an Oracle database. Using Oracle RMAN, you can take a hot backup for your database, which will take a consistent backup even when your DB is up and running.

Can you use RMAN to backup Oracle database?

Only RMAN understands the format of these files. So, if you backup an Oracle DB using RMAN, only RMAN knows how to read the backup and restore it .

What is RMAN image copy?

RMAN can use image copies created by mechanisms outside of RMAN, such as native operating system file copy commands or third-party utilities that leave image copies of files on disk. These copies are known as user-managed copies or operating system copies.

What is proxy copy in RMAN?

During a proxy copy, RMAN turns over control of the data transfer to a media manager that supports this feature . Proxy copy can only be used with media managers that support it, not with disk. The PROXY option of the BACKUP command specifies that a backup should be a proxy copy.

Can RMAN create a backup?

RMAN can create backups on disk or a third-party media device such as a tape drive. If you specify DEVICE TYPE DISK, then your backups are created on disk, in the file name space of the target instance that is creating the backup. You can make a backup on any device that can store a datafile.

Can RMAN read multiple files?

In this case, RMAN simultaneously reads multiple files from disk and and then writes their blocks into the same backup set. (Image copies, by contrast, are never multiplexed.) For example, RMAN can read from two datafiles simultaneously, and then combine the blocks from these datafiles into a single backup piece.