Shulou(Shulou.com)06/01 Report--

In this issue, the editor will bring you about how to backup and restore ORACLE RMAN. The article is rich in content and analyzes and narrates it from a professional point of view. I hope you can get something after reading this article.

RMAN can perform incremental backups: databases, tablespaces, data files

Only used block can be backed up as backup set

Correspondence between tablespaces and data files: dba_data_files / v$datafile_header

In noarchivelog mode, you can use RMAN to back up the table spaces of read-only and offline

ORACLE RMAN downtime backup:

Backup

RMAN connection under ORACLE,WINDOWS in command mode

RMAN TARGET /

The local authentication mode is used to connect to the local database. The RMAN connection database must be in dedicate mode. Therefore, the database in share mode should configure a dedicate connection for RMAN connections.

If you want to back up the control files and parameter files together

Configure controfile autobackup on;// opens autobackup

Configure controfile autobackup off;// shuts down autobackup

Shut down the database

RMAN > shutdown immediate

The backup of mount database RMAN must be in MOUNT mode, which is important to control file backup.

RMAN > startup mount

The simplest backup

RMAN > backup database

That's it, OK.

For such a backup, the backup set is in the default location of the database. % oracle_home%/ora92/database

Of course, you can also use run to define your backup flexibly.

RMAN > run {

> allocate chennel D1 type disk; / / assign channels

> backup full database / / full backup of the database

> include current controlfile / / including the current controlfile

> format'e:\ oracle\ orders\ db_%d_%s_%p_%t_%T'; / / backup file location and file name format

> release channel d1bomber / release channel

>}

Restore

1. The data file is corrupted, but the control file is good, or has been restored.

RMAN connects to the database

Startup mount

Restore database

Recover database noredo

Alter database open resetlogs

Recover database noredo this command instructs RMAN to perform the final restore operation in preparation for opening the database. Because it is in NOARCHIVELOG mode and no archived redo logs are applied and the online redo logs are lost, the noredo parameter is required in this command.

Finally, open the database using alter database open resetlogs. Because the control file has been restored and the redo log needs to be rebuilt, you must use resetlogs.

2. Restore control files

Startup nomount

Set dbid =

Restore controlfile from autobackup

Alter database mount

Restore database

Recover database noredo

Alter database open resetlogs

Alter database open

In this example, there is a DBID that can

Found in select * from v$database. But a database in the control file is broken, how can OPEN see it? this is to write down the DBID at ordinary times.

This is the simplest example of backup and recovery with RMAN, but you can see the outline of RMAN backup and recovery.

ORACLE RMAN online backup:

1. Before ORACLE RMAN online backup, you need to change the log mode to archive log.

a. Shut down the database

SQL > shutdown immediate

b. Start the database to mount state

SQL > startup mount

c. Enable archive mode

SQL > alter database archivelog

d. View the modified database backup and recovery strategy and the location of the archived files

SQL > archive log list

Note: after changing to archive mode, all previous database backups are invalid.

e. Modify the corresponding initialization parameters

Before Oracle10g, you also need to modify the initialization parameters to put the database in automatic archiving mode.

You can view it with SQL > show parameter log_archive_start;.

NAME TYPE VALUE

Log_archive_start boolean FALSE

SQL > alter system set log_archive_start=true scope=spfile

Restart the database this parameter takes effect, and the database is in automatic archiving mode.

Of course, you can skip step 5 and go directly.

SQL > archive log start

Enable automatic archiving of the database, but the database is still in manual archiving mode after restart.

two。 Run: RMAN target /

3. Save RMAN information: it is saved in control file by default with a preservation period of 7 days.

Adjust: alter system set control_file_record_keep_time= days

4. Set up an independent database to save RMAN backup information

Since there is only one database, it is built on its own database.

a. Create tablespace RC:create tablespace rc datafile size 10m autoextend on next 1m

b. Create a user RC:

CREATE USER rc IDENTIFIED BY rc TEMPORARY TABLESPACE temp DEFAULT TABLESPACE rc QUOTA UNLIMITED ON rc

c. Authorized RC: GRANT RECOVERY_CATALOG_OWNER TO rc

d. Build:

Rman catalog rc/rc@orcl

RMAN > create catalog

RMAN > exit

Rman target / catalog rc/rc@orcl

RMAN > register database

e. Use:

Rman target / catalog rc/rc@orcl

After this connection, the data will be stored in the control file and one copy each in the catalog

5. Global parameter configuration:

Viewing: show all

Modify: specific settings of configure parameter name

For example: modify whether to automatically save controlfile: configure controlfile autobackup on

Restore default value: configure parameter name clear

Key parameters:

a. Save cycle: retention policy

Default is redundancy 1: keep a backup

Available value: recovery window of 7 days: keep backups that meet the 7-day recovery cycle

Check based on condition: report obsolete:RMAN lists backups that can be deleted based on the save cycle parameter

Delete more than backup: delete obsolete

b. Optimized backup: backup optimization:RMAN automatically ignores content that has been backed up (data files, archive logs, backup blocks)

Prerequisite: backup specifies the same channel

c. Default backup channel: default device type to disk: default backup to disk, path is flash recovery area

Channel Type:

Disk: file system path

Flash recovery area: default path

Sbt: tape Devic

Modify to another path to disk: configure channel device type disk format 'path /% U'

For example: configure channel device type disk format'/ tmp/movedata/%U'

6. Backup result

Backupset:backup (as backupset) backup content, which is divided into one or more backup piece, only this type of backup can be compressed.

Copy:backup as copy backup content

View by type:

Backupset View: list backup summary (list backupset summary)

View details: list backupset BS

Copy View: list copy

View by content:

Entire database: list backup of database

Tablespace:list backup of tablespace users

Data file: list backup of datafile n

Control file: list backup of controlfile

Archive logs: list archivelog all

View by rule:

View files that can be deleted according to save rules: report obsolete

View what needs to be backed up according to the save rules: report

Combined inspection of RMAN and OS: corsscheck content

7. Backup mode

Full: complete

Incremental: incremental backup

Types of incremental backups: databases, data files, tablespaces

a. First of all, you need to do a level 0 backup as a basis. For example: backup incremental level 0 backup content; (backup content: all used data block, different from image copy)

b. Increment type:

Cumulative increment: backup cumulative level 1 backup content

Differential increment: backup incremental level 1 backup content

Difference: cumulative increments are always level 0-based backups

The first differential increment is based on level 0 backup; from the second, it is based on the previous incremental backup.

C. Image backup increment method:

The first time: based on the complete Image

The second time: based on complete, do incremental backup; after completion, synthesize into a complete Image

The third time: make incremental backup based on the second complete Image, and synthesize it into a complete Image after completion

Achieve:

For example: for tablespace example

RUN {

RECOVER COPY OF tablespace example WITH TAG 'incr_update'

BACKUP INCREMENTAL LEVEL 1 FOR RECOVER OF COPY WITH TAG 'incr_update'

Tablespace example

}

d. Enable the parameter "block change tracking" to improve the speed

View status: SELECT status FROM v$block_change_tracking

Default value: DISABLED

Enable: ALTER DATABASE ENABLE BLOCK CHANGE TRACKING; (DB_CREATE_FILE_DEST in the default storage path OMF)

Set the file path:

ALTER DATABASE ENABLE BLOCK CHANGE TRACKING USING FILE'/ u01 REUSE oradata REUSE

Turn off: ALTER DATABASE DISABLE BLOCK CHANGE TRACKING

Backup and check: bakcup check logical backup contents

No backup, just check the file: backup validate backup contents

If an error is reported in the check, check: vogue backupsetting corruptionwitch vandalism copywriting

8. Backup content:

The whole database: RMAN > backup database

Classic full library backup: backup as compressed backupset database include current controlfile plus archivelog delete input

Tablespace:RMAN > backup tablespace name

Data file: RMAN > backup datafile n; (n: specific data file number select file_name,file_id,tablespace_name from dba_data_files;)

Control file: RMAN > backup current controlfile

Or RMAN > backup database include current controlfile

Log file: RMAN > backup archivelog all

Or RMAN > backup database plus archivelog

Parameter file: RMAN > backup spfile

9. Reduction

a. Complete recovery

Method 1: restore the entire database from the most recent backup set, and the database automatically runs redo and archive logs (full recovery):

SQL > shutdown immediate

SQL > startup mount

RMAN > restore database

RMAN > recover database

RMAN > sql 'alter database open'

Method 2: restore the entire database from tag, and the database also runs redo and archive logs (full recovery), and the result is the same as the script above:

1. View the label:

RMAN > list backupset summary

Key TY LV S Device Type Completion Time # Pieces # Copies Compressed Tag

25 B An A DISK 25-JUL-11 11 NO TAG20110725T104634

28 B 0 A DISK 25-JUL-11 11 NO TAG20110725T104645

29 B An A DISK 25-JUL-11 11 NO TAG20110725T104711

30 B F A DISK 25-JUL-11 11 NO TAG20110725T104713

31 B An A DISK 25-JUL-11 11 NO TAG20110725T105333

32 B An A DISK 25-JUL-11 11 NO TAG20110725T105350

33 B 1 A DISK 25-JUL-11 11 NO TAG20110725T105353

34 B An A DISK 25-JUL-11 11 NO TAG20110725T105408

35 B F A DISK 25-JUL-11 11 NO TAG20110725T105411

36 B An A DISK 25-JUL-11 11 NO TAG20110725T111403

37 B 1 A DISK 25-JUL-11 11 NO TAG20110725T111405

38 B An A DISK 25-JUL-11 11 NO TAG20110725T111421

39 B F A DISK 25-JUL-11 11 NO TAG20110725T111423

two。 Restore the database:

SQL > shutdown immediate

SQL > startup mount

RMAN > restore database from tag TAG20110725T104645

RMAN > recover database from tag TAG20110725T104645

RMAN > alter database open

b. Incomplete recovery:

SQL > shutdown immediate

SQL > startup mount

RMAN > restore database from tag TAG20110725T104645

RMAN > recover database until time "to_date ('2011-08-04 15 to_date 3714 25mm hh34:mi:ss')"

RMAN > alter database open resetlogs

Note: all backup sets are invalid after use. To ensure security, you need to recomplete the database (after ORACLE10G, backups before resetlog are still available).

Critical tablespace recovery (system / undotbs1 / sysaux):

SQL > shutdown abort

SQL > startup mount

RMAN > restore tablespace name

RMAN > recover tablespace name

RMAN > sql 'alter database open'

Non-critical tablespace recovery (example / users):

Select * from vested datafile headers; correspondence between tablespaces and data files

SQL > alter database datafile Digital offline

RMAN > restore tablespace name

RMAN > recover tablespace name

SQL > alter database datafile Digital online

10. Delete backup

All backup backup sets: delete backup

All copy backup machines: delete copy

Specific backup: delete backupset 19

Delete Files can be deleted according to save rules: delete obsolete

Delete expired backups:

Delete expired backupset

Delete expired copy

11. RUN block

For example:

RMAN > RUN {

ALLOCATE CHANNEL c1 DEVICE TYPE sbt

ALLOCATE CHANNEL c2 DEVICE TYPE sbt

ALLOCATE CHANNEL c3 DEVICE TYPE sbt

BACKUP

INCREMENTAL LEVEL = 0

FORMAT'/ disk1/backup/df_%d_%s_%p.bak'

(DATAFILE 1, 4, 5, CHANNEL C1)

(DATAFILE 2, 3, 3, 9 CHANNEL c2)

(DATAFILE 6, 7, 8, CHANNEL c3)

ALTER SYSTEM ARCHIVE LOG CURRENT

}

twelve。 External variables:

Language: set nls_lang=american

Date: set nls_date_format=yyyy-mm-dd....

13. RMAN sciprt

Prerequisites: have catalog

Written: (global indicates that it can be called by multiple databases)

Create global script. Name

Comment "remarks"

{script content}

For example:

Create global script. Abc

Comment "test"

{backup current controlfile;}

Call: run {execute script. First name}

For example: run {execute script. Abc;}

View: print script. Name

Rewrite:

Replace global script. Name

Comment "remarks"

{script content}

Delete: delete script. First name

14. Permanent retention backup

The condition is that the backup cannot be kept in flash recovery area.

a. Create a backup:

RUN

{

ALLOCATE CHANNEL C1 DEVICE TYPE disk format'/ tmp/autobackup/%U'

BACKUP tablespace example

}

b. Find the backup:

List backupset of tablespace example

c. Change the property to permanent

Change backupset number keep forever nologs

15. Establish multiple fixed-size backups

For example: example test backup size is greater than 50m

Run

{

Allocate channel C1 device type disk maxpiecesize 10m format'/ tmp/autobackup/%U'

Backup tablespace example

}

There are six files in / tmp/autobackup directory

16. Run script: backup recovery area

Backup content:

A. Control file autobackup

B. Incremental backup sets

17.block change tracking

a. For the entire database

b. Default storage path: background_dump_dest

The above is the editor for you to share how to carry out ORACLE RMAN backup and restore, if you happen to have similar doubts, you might as well refer to the above analysis to understand. If you want to know more about it, you are welcome to follow the industry information channel.

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