If you ...	Then ...
Create a new dat abase in the current release	The snapshot control file location u ses the default value. In this case, the default snapshot control file location changes if you change the Oracle home.
Upgrade to the current rel ease from a release prior to 8.1.7	The snapshot control file loca tion is not set to the default value. Instead, RMAN uses the snapshot location that is already stored in the control file. In this ca se, the snapshot control file location does not change if you change the Oracle home.

6
Configuri ng the RMAN Environment: Advanced Topics

This chapter describ es how to perform setup and configuration tasks. This chapter contains these topics:

Configuring the Flash Recovery Area: Advanced Topics

To take maximum advantage of the flash recovery area, it should be used to store and manage as many different types of file as possible: online redo logs, archived redo logs, control files and RMAN's own working files for backu p and restore operations.

This section contains the following topics:

The following statements can create online redo logs in the f lash recovery area:

CREATE DATABASE
ALTER DATABASE ADD LOGFILE
ALT ER DATABASE ADD STANDBY LOGFILE
ALTER DATABASE OPEN RESETLOGS


 
The default size of an online log created in the flash recovery area is 100 MB. T
he log member filenames are automatically generated by the database.

The initialization par ameters that determine where online redo log files are created are DB_CREATE_ONLINE_LOG_DEST_n, DB_RECOVERY_FILE_DEST and DB_CREATE_FILE_DEST. Details of the effect of various combinations of these paramet ers on online redo log creation can be found inOracle Database SQL Reference in the description of the LOGFILE clause of the C REATE DATABASE statement.

Configuring Control File Creation in the Flash Recovery Area

The initialization parameters CONTROL_FILES, DB_CREATE_ONLINE _LOG_DEST_n, DB_RECOVERY_FILE_DEST, and DB_CREATE_FILE_DEST all interact to de termine the location where the database control files are created.

For a full description o f how these parameters interact, see the "Semantics" section of the description of CREATE CONTROLFILE in Oracle Database SQL Reference.

If the database creates an Oracle managed control file, and if the database uses a serv er parameter file, then the database sets the CONTROL_FILES initialization parameter in the server parameter file. If th e database uses a client-side initialization parameter file, then you must set the CONTROL_FILES initialization paramete r manually in the initialization parameter file.

Archived Redo Log Creation in the Flash Recovery Area

It is recommended that you the use flash recovery area as an archived log location because the archived log s are automatically managed by the database. Whatever archiving scheme you choose, it is always advisable to create multiple copies o f archived logs.

You have the following basic options, listed from most to least recommende d:

Enable archiving to the flash recovery area only and use disk mirroring to create copies of the archived redo logs.
Enable archiving to the flash recovery area and set other LOG_ARCHIVE_DEST_n initialization parameter to locations outside the flash recovery area.

Set LOG_ARCHIVE_DEST_n initialization parameters to archive only to n on-flash recovery area locations.

If you want to use the flash recovery area, you can not use the LOG_ARCHIVE_DEST and LOG_ARCHIVE_DUPLEX_DEST initialization parameters. You must use instead th e LOG_ARCHIVE_DEST_n parameters, which have somewhat different semantics. Once your database is us ing LOG_ARCHIVE_DEST_n, you can configure a flash recovery area.

Rules for Initialization Parameters Affect ing Redo Log File Destinations

The interactions among different init ialization parameters affecting redo log archiving desintations are as follows:

If LOG_ARCHIVE_DEST (and, optionally, LOG_ARCHIVE_DUPLEX_DEST) is set, these parameters w ill specify the only redo log archiving destinations.

If DB_RECOVERY_FIL E_DEST is specified (that is, if a flash recovery area is configured) and no LOG_ARCHIVE_DEST_n is specified, then LOG_ARCHIVE_DEST_10 is implicitly set to the flash recovery area. (You can override this behavio r by explicitly setting LOG_ARCHIVE_DEST_10 to an empty string.)

If you set any local destinations for LOG_ARCHIVE_DEST_n, then archived redo logs are stored only in the destinations you specify using those parameters. In this case, redo log files are not archived in the flash recovery area by d efault. If you have a flash recovery area configured, you can explicitly add the flash recovery area to the set of archiving destinat ions by setting one of the LOG_ARCHIVE_DEST_n parameters to LOCATION=USE_DB_RECOVERY_FILE_DE ST (note that this does not have to be LOG_ARCHIVE_DEST_10).

< /a>If you do not set any value for LOG_ARCHIVE_DEST, LOG_ARCHIVE_DEST_n, or DB_ RECOVERY_FILE_DEST, then the redo logs are archived to a default location that is platform-specific. On Solaris, for example, the default is ?/dbs.

Filenames for Archived Redo Log Files in the Flash Recovery Area

The generated filenames for the archived redo logs in the flash recovery area are Oracle Manged Filename s and are not determined by LOG_ARCHIVE_FORMAT.

RMAN File Creation in the Flash Recovery Area

This section describes RMAN commands or implicit actions (such as control file autobackup) that can cre ate files in the flash recovery area, and how to control whether a specific command creates files there or in some other destination. The assumption in all cases is that a flash recovery area has already been configured for your database. The commands are:

BACKUP

Do not specify a FORMAT option to the BACKUP command, and do not configure a FORMAT option for disk backups. In such a case, RMAN creates backup pieces and image copies in the flash recovery area, with names in Orac le Managed Files name format.

Control File Autobackup

RMAN can create control file autobackups in the flash recovery area. Use the RMAN command CONFIGURE CONTROLFILE AUTOBACKUP FORMAT FOR DEVICE TYPE DISK CLEAR to clear any configured format option fo r the control file autobackup location on disk. Control file autobackups will be placed in the flash recovery area when no other dest ination is configured.

RESTORE ARCHIVELOG 

Explicitly or implicitly (as in the case of ), set one of the LOG_ARCHIVE_DEST_n) parameters to 'LOCATION=USE_DB_RECOVERY_FILE_DEST'. If you do not specify SET ARCHIVELOG DESTINATION to override t his behavior, then restored archived redo log files will be stored in the flash recovery area.
< a name="1014239">RECOVER DATABASE or TABLESPACE, BLOCKR ECOVER, and FLASHBACK DATABASE These comm ands restore archived redo logs from backup for use during media recovery, as required by the command. RMAN restores any redo log fil es needed during these operations to the flash recovery area, and delete them once they are applied during media recovery. To direct the restored archived redo logs to the flash recovery area, set one of the LOG_ARCHI VE_DEST_n parameters to 'LOCATION=USE_DB_RECOVERY_FILE_DEST", and make sure you are not usi ng SET ARCHIVELOG DESTINATION to direct restored archived logs to some other destination.
Configurin g RMAN to Make Backups to a Media Manager On most platforms, to back up to and restore from sequential media such as tape you must integrate a media manager with your Oracle database. A media manag er is not an Oracle product and must be obtained from a third-party vendor. If you choose to use RMAN with a media manager, then you must obtain all product-specific information from the vendor. This section describes the ge neric steps for configuring RMAN for use with a media manager. The actual steps depend on the media management product that you insta ll and the platform on which you are running the database. Read the following sections in o rder when configuring the media manager: Prerequisites for Using a Media Manager with RMAN Locating the Media Management Library: The SBT_LIBRARY Parameter Testing Whether the Media Manager Library Is Integrated Correctl y Configuring Automatic Channels for Use with a Media Manager See Also: "Media Management" for an overview of media management software and its implications for RMAN Prerequisites fo r Using a Media Manager with RMAN Before you can begin using RMAN wi th a media manager, you must install it and make sure that RMAN can communicate with it. Instructions for this procedure should be av ailable in the media manager vendor's software documentation. In general, you should begin by installing and configuring the media management software on the target host or production network. Ensure that you can make non-RM AN backups of operating system files on the target database host. This step makes later troubleshooting much easier, by confirming th at the basic integration of the media manager with the target host has been successful. Refer to your media management documentation to learn how to back up files to the media manager outside of RMAN. Then, obtain and instal l the third-party media management module for integration with the database server. This module contains the media management library that the Oracle database loads and uses when accessing the media manager. It is generally a third-party product which must be purcha sed separately. Contact your media management vendor for details. Locating the Media Management Library: The SBT_LIBRARY Parameter When allocating or configuring channels for RMAN to use to communicate with a m edia manager, specify the SBT_LIBRARY parameter to provide the path to the media management software library. When RMAN actually allocates channels to communicate with a media manager, it attempts to load the library indicated by the SBT_LIBRARY parameter. If you do not provide a value for this parameter, RMAN looks in a platform -specific default location. On UNIX, the default library filename is $ORACLE_HOME/lib/libobk.so, with the extension name varying according to platform: .so, .sl, .a, and so forth. On Windows the default library loc ation is %ORACLE_HOME%\bin\orasbt.dll. Note: The default media management library file is not part of the standard database installation. It is only present if you install third-party media management software. If the database is unable to locate a media management library in th e location specified by the SBT_LIBRARY parameter or the default location, then RMAN issues an ORA-27211 er ror and exits. Whenever channel allocation fails, the database writes a trace file to the < code>USER_DUMP_DEST directory. The following shows sample output: SKGFQ OSD: Error in function sbtinit on line 2278 SKGFQ OSD: Look for SBT Trace messages in file /oracle/rdbms/log/sbtio.log SBT Initialize failed for /oracle/lib/libobk.so See Also: Your operating system specific Oracle documentation and the documentation supplied by your media vendor for instructi ons on how to achieve media manager integration on your platform "After Installation of Media Manager, RMAN Channel Allocation Fails: Scenario" for troubleshooting scenarios involving media manager problems Testing Whether the Media Manager Library Is In tegrated Correctly After you have confirmed that the database server can load the media management library, test to make sure that RMAN can back up to the media manager. The process for testing the med ia management library is described in the following sections: Configuring Media Management Software for RMAN Backups Testing ALLOCATE CHANNEL on the Media Manager Testing a Backup to the Media Manager Configuring Media Management Software for RMAN B ackups After installing the media management software, perform whate ver configuration that your vendor requires so that the software can accept RMAN backups. Depending on the type of media management s oftware that you installed, you may have to define media pools, configure users and classes, and so forth.
Then, determine which PARMS settings are needed for the ALLOCATE CHANNEL or CONFIGURE CHANNEL commands as well as the recommended FORMAT string for the BACKUP command (if needed). The PARMS parameter sends instructions to the media manager. For example, the following vendor-spec ific PARMS setting instructs the media manager to back up to a volume pool called oracle_tapes:

PARMS='ENV=(NSR_DATA_VOLUME_POOL=oracle_tapes)'

Refer to your third-party vendor documentation for the appropriate settings.

See Also:

Oracle Database Recovery Manager Reference for ALLOCATE CHANNEL syntax

Oracle Database Recovery Manager Reference for channel control options

Configuring Backup Piece Names and Sizes for a Media Manager

To work with restri ctions on file names and sizes imposed by your media manager, you may need to configure RMAN settings that control the naming and siz e of backup pieces.

Configuring Backup Piece Names for RMAN Backups to a Media Manager

You may need to manage the naming of backup pieces to be written to the media manager, so that backup pieces have unique na mes. A backup piece name is determined by the FORMAT string specified in the BACKUP command, the CONF IGURE CHANNEL command, or the ALLOCATE CHANNEL command. The media manager considers the backup piece name as the filename of the backup file, so this name must be unique in the media manager catalog.

You can use the substitution variables provided by RMAN to generate unique backup piece names. If you do not specify the FORMAT parameter, then RMAN automatically generates a unique filename with the %U substitution variable.
< a name="1006666">

Note: Refer to your media management documentation to determine the string character limit for the media manager. For example, some media managers only support a 14-character backup piece name, and some require special FORMAT strings. The unique backup piece names generated by %U are less than 14 characters.

See Also:
Oracle Database Recovery Manager Reference f or the complete list of variables allowable in format strings with the BACKUP command

Configuring Backup Piece Sizes for RMAN Backups to a Media Manager

Some media managers have limits on the maximum size of files that they can back up or restore. You must ensure that RMAN does not produce backup sets lar ger than limits imposed by your media manager.

To limit backup piece sizes, use the paramet er MAXPIECESIZE, which you can set in the CONFIGURE CHANNEL and ALLOCATE CHANNEL commands. Ref er to the *.rcv scripts in the demo subdirectory on your system, which is located in an operating system sp ecific location ($ORACLE_HOME/rdbms on UNIX) for an example.

Testing ALLOCATE CHANNEL on the Media Manager
Use the follow ing steps to confirm that RMAN is able to load the media management library when allocating a channel for your media manager.

Start RMAN and connect to the target database. For ex ample, enter:
% rman TARGET /

Run the ALLOCATE CHANNEL command with the PARMS required by your media management software. For example, run this command:
RUN { ALLOCATE CHANNEL c1 DEVICE TYPE sbt PARMS='SBT_LIBRARY=/mediavendor/lib/libobk.so ENV=(N SR_SERVER=tape_ srv,NSR_GROUP=oracle_tapes)'; }

If you do not receive an error message, then the database successfully loaded the media management library. If you rec eive the ORA-27211 error, the media management library could not be loaded:
RM AN-00571: =========================================================== RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS =============== RMAN-00571: =========================================================== RMAN-03009: failure of allocate command on c1 channel at 11/30/2001 13:57:18 ORA-19554: error all ocating device, device type: SBT_TAPE, device name: ORA-27211: Failed to load Media Management Library Additional information: 25
In this case, you must check your media management installation to make sure that the library is correctly installed, and re-check the value for the SBT_LIB RARY parameter as described in "Locating the Media Management Library: The SBT_LIBRARY Parameter"< a href="rcmconfg.htm#1012649">.
For any other errors, check the trace file in USE R_DUMP_DEST directory for more information.

See Also:
Oracle Database Recovery Manager Reference and "Size of Backup Pieces"for details on how to set MAXPIECESIZE

See Also:
"After Installation of Media Manager, RMAN Channel Allocation Fails: Scenario" for a troubleshooting scenario

Testing a Backup to the Media Manager

After testing a channe l allocation on the media manager, make a test backup. For example, to test whether your backup goes successfully to tape, you might run the following command:

RUN { ALLOCATE CHA NNEL c1 DEVICE TYPE sbt PARMS='SBT_LIBRARY=/mediavendor/lib/libobk.so ENV=(NSR_SERVER=tape_srv,NSR_ GROUP= oracle_tapes)'; BACKUP CURRENT CONTROLFILE; }

The specifics of your PARMS and FORMAT settings depend on the media management s oftware that you are using.

If the backup succeeds, then you are ready to make backups to y our media manager.

Possible failures include the following cases:

Case Response

The backup hangs.

A hanging backup usually indicates that the media manager is waiting to mount a tape. Check if there are any m edia manager jobs in "tape mount request" mode and fix the problem.

Ensure that the steps in "Configuring RMAN to Make Backups to a Media Manager" are corr ectly done. Refer to "Backup Job Is Hanging: Scenario" if the p roblem persists.

The backup fails with an ORA-19511

This error i ndicates that the media management software is not correctly configured. Ensure that the steps in "Con figuring RMAN to Make Backups to a Media Manager" are correctly done. Also, ensure that you ha ve the correct PARMS and FORMAT strings required by your media management software.

See Also:
"Testing the Media Management API" and "RMAN Troubleshooting Scenarios" for more information ab out troubleshooting RMAN with a media manager

Oracle® Database Backup and Recovery Advanc ed User's Guide 10g Release 1 (10.1) Part Number B10734-01
Home	Book List	Contents	Index	Master Index	Feedback

Channel Name	Setting
`ORA_DISK_1`	`FORMAT` `=` `'/tmp/backup_%U'`
`ORA_DISK_2`	`MAXPIECESIZE` `=` `20M`
`ORA_DISK_3`	`FORMAT` `=` `'/tmp/backup_%U'`
`ORA_DISK_4`	`MAXPIECESIZE` `=` `40M`

Channel Name	Setting
`ORA_SBT_TAPE_1`	`PARMS='ENV=(BACKUP_DIR=?/oradata)'`
`ORA_SBT_TAPE_2`	`PARMS='ENV=(BACKUP_DIR=?/oradata)'`
`ORA_SBT_TAPE_3` < /td>	`PARMS='ENV=(BACKUP_DIR=/tmp)'`

6 Configuri ng the RMAN Environment: Advanced Topics

Configuring Control File Creation in the Flash Recovery Area

Archived Redo Log Creation in the Flash Recovery Area

Rules for Initialization Parameters Affect ing Redo Log File Destinations

Filenames for Archived Redo Log Files in the Flash Recovery Area

RMAN File Creation in the Flash Recovery Area

Prerequisites fo r Using a Media Manager with RMAN

< font face="Arial, Helvetica, sans-serif" color="#330099">Locating the Media Management Library: The SBT_LIBRARY Parameter

Testing Whether the Media Manager Library Is In tegrated Correctly

Configuring Media Management Software for RMAN B ackups

Configuring Backup Piece Names and Sizes for a Media Manager

Configuring Backup Piece Names for RMAN Backups to a Media Manager

Configuring Backup Piece Sizes for RMAN Backups to a Media Manager

Testing ALLOCATE CHANNEL on the Media Manager

Testing a Backup to the Media Manager

Configuring Automatic Channels for Use with a Media Manager

Configuring a Generic Automatic Channel for a Device Type

Configured Channels and the Def ault Device Type

Showing the Automatic Channel Configuration Settings

Showing the Automatic Channel Settings

Manually Overriding Co nfigured Channels

Configuring a Specific Channel for a Device Type

Configuring S pecific Channels: Examples

Mixing Generic and Specific Chann els

Relations hip Between CONFIGURE CHANNEL and Parallelism Setting

Clearing Channel and Device Settings

Showing the Default Maximum Size of Backup Sets: SHOW MAXSETSIZE

Displaying Backup Optimization Setting : SHOW BACKUP OPTIMIZATION

Showing the Configured Degree of Duplexing: SHOW... BACKUP COPIES

Showing the Tablespaces Excluded from Backups

Showing the Default Filenames Configured for Auxiliary Channels

Default Location of the Snapshot Control Fi le

Viewing the Configu red Location of the Snapshot Control File

Setting the Location of t he Snapshot Control File

Showing the Current Snapshot Control File Name

6
Configuri ng the RMAN Environment: Advanced Topics