Oracle RMAN 映像備份（Image copies）基本原理與方案

luashin發表於2016-03-22
Oracle

   映像級別備份（image copies）相當於資料檔案和歸檔日誌的複製複製品，與原檔案在儲存空間上完全一致，如果需要做一個部分恢復（比如某一資料檔案）採用映像備份情況下只需要檢索相應的映像即可，恢復速度非常快，在某些非常情況下，可以直接switch到映像資料檔案以保證生產環境儘可能短時間的停機，事後再做一個copy到原路徑，選擇空閒時段再次swich回去。

   鑑於映像備份需要佔用和生產資料檔案相同的空間，所以在資料量較大的情況下是不建議採用的，因為這種方案需要客戶為花費雙份儲存的錢，但是如果說在某庫建立之初，資料檔案不是很大，或者說某庫資料量始終較小，那麼選擇影響備份是一種極好的方案，可以在資料檔案出現物理損壞時，以最短的時間完成介質恢復。

下面介紹一些最簡單的RMAN映像備份方案

1、開啟rman塊追蹤技術

SQL> alter database enable block change tracking using file '/u01/app/oralce/oradata/orcl/block_change_track_file.f';

Database altered.


2、進行映像級別的level 0備份

run {

ALLOCATE CHANNEL "ch1" DEVICE TYPE DISK FORMAT "/u04/%U";

BACKUP AS COPY TAG 'BASE01' INCREMENTAL LEVEL 0 DATABASE;

}

3、進行映像級別的level 1備份

$ rman target /

run {

ALLOCATE CHANNEL "ch1" DEVICE TYPE DISK FORMAT "/u04/%U";

BACKUP TAG 'incr_update' INCREMENTAL LEVEL 1 DATABASE;

}

4、用level 1的備份update level 0 中的映像

run {
ALLOCATE CHANNEL "ch1" DEVICE TYPE DISK FORMAT "/u04/%U";
RECOVER COPY OF DATABASE WITH TAG 'BASE01';

 }

實驗紀錄

1、level 0

RMAN> run {

ALLOCATE CHANNEL "ch1" DEVICE TYPE DISK FORMAT "/u04/%U";

BACKUP AS COPY TAG 'BASE01'

INCREMENTAL LEVEL 0

DATABASE;

}

2> 3> 4> 5> 6>

released channel: ORA_DISK_1

allocated channel: ch1

channel ch1: SID=32 device type=DISK


Starting backup at 05-SEP-13

channel ch1: starting datafile copy

input datafile file number=00001 name=/u01/app/oralce/oradata/orcl/system01.dbf

output file name=/u04/data_D-ORCL_I-1349053318_TS-SYSTEM_FNO-1_0coj3jug tag=BASE01 RECID=18 STAMP=825348067

channel ch1: datafile copy complete, elapsed time: 00:00:25

channel ch1: starting datafile copy

input datafile file number=00002 name=/u01/app/oralce/oradata/orcl/sysaux01.dbf

output file name=/u04/data_D-ORCL_I-1349053318_TS-SYSAUX_FNO-2_0doj3jv9 tag=BASE01 RECID=19 STAMP=825348091

channel ch1: datafile copy complete, elapsed time: 00:00:25

channel ch1: starting datafile copy

input datafile file number=00005 name=/u01/app/oralce/oradata/orcl/example01.dbf

output file name=/u04/data_D-ORCL_I-1349053318_TS-EXAMPLE_FNO-5_0eoj3k02 tag=BASE01 RECID=20 STAMP=825348107

channel ch1: datafile copy complete, elapsed time: 00:00:15

channel ch1: starting datafile copy

input datafile file number=00004 name=/u01/app/oralce/oradata/orcl/users01.dbf

output file name=/u04/data_D-ORCL_I-1349053318_TS-USERS_FNO-4_0foj3k0h tag=BASE01 RECID=21 STAMP=825348116

channel ch1: datafile copy complete, elapsed time: 00:00:03

channel ch1: starting datafile copy

input datafile file number=00003 name=/u01/app/oralce/oradata/orcl/undotbs01.dbf

output file name=/u04/data_D-ORCL_I-1349053318_TS-UNDOTBS1_FNO-3_0goj3k0l tag=BASE01 RECID=22 STAMP=825348120

channel ch1: datafile copy complete, elapsed time: 00:00:07

Finished backup at 05-SEP-13


Starting Control File and SPFILE Autobackup at 05-SEP-13

piece handle=/u01/app//product/11.2.0/dbhome_1/dbs/c-1349053318-20130905-00 comment=NONE

Finished Control File and SPFILE Autobackup at 05-SEP-13

released channel: ch1


RMAN>


2、做一些操作，比如建立一個表

SQL> create table rmantest1 as select * from rmantest;

Table created.


SQL> commit;

Commit complete.


SQL> select count(*) from rmantest1;

  COUNT(*)

----------

  2209792

 

3、level 1

RMAN> run {

ALLOCATE CHANNEL "ch1" DEVICE TYPE DISK FORMAT "/u04/%U";

BACKUP TAG 'incr_update'

INCREMENTAL LEVEL 1

DATABASE;

}

2> 3> 4> 5> 6>

allocated channel: ch1

channel ch1: SID=37 device type=DISK


Starting backup at 05-SEP-13

channel ch1: starting incremental level 1 datafile backup set

channel ch1: specifying datafile(s) in backup set

input datafile file number=00001 name=/u01/app/oralce/oradata/orcl/system01.dbf

input datafile file number=00002 name=/u01/app/oralce/oradata/orcl/sysaux01.dbf

input datafile file number=00005 name=/u01/app/oralce/oradata/orcl/example01.dbf

input datafile file number=00004 name=/u01/app/oralce/oradata/orcl/users01.dbf

input datafile file number=00003 name=/u01/app/oralce/oradata/orcl/undotbs01.dbf

channel ch1: starting piece 1 at 05-SEP-13

channel ch1: finished piece 1 at 05-SEP-13

piece handle=/u04/0loj3khg_1_1 tag=INCR_UPDATE comment=NONE

channel ch1: backup set complete, elapsed time: 00:00:15

Finished backup at 05-SEP-13


Starting Control File and SPFILE Autobackup at 05-SEP-13

piece handle=/u01/app//product/11.2.0/dbhome_1/dbs/c-1349053318-20130905-03 comment=NONE

Finished Control File and SPFILE Autobackup at 05-SEP-13

released channel: ch1

 

4、update image copy with incremental level 1

RMAN> run {

ALLOCATE CHANNEL "ch1" DEVICE TYPE DISK FORMAT "/u04/%U";

RECOVER COPY OF DATABASE WITH TAG 'BASE01';

 }

2> 3> 4>

using target database control file instead of recovery catalog

allocated channel: ch1

channel ch1: SID=32 device type=DISK


Starting recover at 05-SEP-13

channel ch1: starting incremental datafile backup set restore

channel ch1: specifying datafile copies to recover

recovering datafile copy file number=00001 name=/u04/data_D-ORCL_I-1349053318_TS-SYSTEM_FNO-1_0coj3jug

recovering datafile copy file number=00002 name=/u04/data_D-ORCL_I-1349053318_TS-SYSAUX_FNO-2_0doj3jv9

recovering datafile copy file number=00003 name=/u04/data_D-ORCL_I-1349053318_TS-UNDOTBS1_FNO-3_0goj3k0l

recovering datafile copy file number=00004 name=/u04/data_D-ORCL_I-1349053318_TS-USERS_FNO-4_0foj3k0h

recovering datafile copy file number=00005 name=/u04/data_D-ORCL_I-1349053318_TS-EXAMPLE_FNO-5_0eoj3k02

channel ch1: reading from backup piece /u04/0loj3khg_1_1

channel ch1: piece handle=/u04/0loj3khg_1_1 tag=INCR_UPDATE

channel ch1: restored backup piece 1

channel ch1: restore complete, elapsed time: 00:00:15

Finished recover at 05-SEP-13


Starting Control File and SPFILE Autobackup at 05-SEP-13

piece handle=/u01/app/oracle/product/11.2.0/dbhome_1/dbs/c-1349053318-20130905-04 comment=NONE

Finished Control File and SPFILE Autobackup at 05-SEP-13

released channel: ch1

來自 “ ITPUB部落格 ” ，連結：http://blog.itpub.net/9034054/viewspace-2061463/，如需轉載，請註明出處，否則將追究法律責任。

相關文章