FRA(Fast Recovery Area)란?

 

Overview of FRA

Backup and Recovery Files를 간단하게 관리하기 위해 Database에 대한 Fast Recovery Area를 생성할 수 있습니다. FRA는 Backup and Recovery Files를 위한 centralized storage location을 제공하는 Oracle-managed directory, file system, or Oracle ASM disk group입니다. Oracle은 FRA에서 archived logs, flashback logs를 생성합니다. RMAN은 backup sets와 image copies를 FRA에 저장할 수 있으며 Media Recovery 중에 Files를 restore할 때 사용합니다.

Oracle은 이 storage를 자동으로 관리하여 더이상 필요하지 않은 files를 삭제합니다. Backup을 tape에 주기적으로 copy하면 다른 files를 위한 FRA free space가 생깁니다.

Backup destination을 지정하지 않고, RMAN BACKUP 명령어를 실행하면 RMAN이 자동으로 FRA에 Backup합니다.

Oracle에서는 Backup Management를 단순화하기 위해 FRA를 구성할 것을 권장합니다. 하지만 실제로 아주많이 쓰이는 기능은 아닙니다.

 

Configuring the FRA

이러한 FRA를 구성한다면, Oracle은 Database Files와 분리된 storage에 위치할 것을 권장합니다.

FRA를 구성하기 위해서는 두가지 Init Parameter를 설정해주어야합니다.

반드시 DB_RECOVERY_FILE_DEST_SIZE를 먼저 설정한 후 DB_RECOVERY_FILE_DEST를 설정해야합니다.

· DB_RECOVERY_FILE_DEST?

FRA의 location을 지정하는 Init Parameter. File system directory 혹은 ASM disk group일 수 있지만 raw disk에는 위치할 수 없습니다.

· DB_RECOVERY_FILE_DEST_SIZE?

FRA의 size를 지정하는 Init Parameter. Bytes단위.

 

구성 과정

· FRA를 구성하지 않은 경우

SQL> show parameter db_recovery_file_dest

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
db_recovery_file_dest                string
db_recovery_file_dest_size           big integer 0

· FRA 구성

SQL> alter system set db_recovery_file_dest_size=3G;

System altered.

SQL> alter system set db_recovery_file_dest='/oracle/fra';

System altered.

SQL> show parameter db_recovery

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
db_recovery_file_dest                string      /oracle/fra
db_recovery_file_dest_size           big integer 3G

· FRA를 확인하는 View

SQL> col name for a20
SQL> select * from v$recovery_file_dest;

NAME                 SPACE_LIMIT SPACE_USED SPACE_RECLAIMABLE NUMBER_OF_FILES
-------------------- ----------- ---------- ----------------- ---------------
/oracle/fra           3221225472          0                 0               0

SQL> select * from v$recovery_area_usage;

FILE_TYPE            PERCENT_SPACE_USED PERCENT_SPACE_RECLAIMABLE NUMBER_OF_FILES
-------------------- ------------------ ------------------------- ---------------
CONTROL FILE                          0                         0               0
REDO LOG                              0                         0               0
ARCHIVED LOG                          0                         0               0
BACKUP PIECE                          0                         0               0
IMAGE COPY                            0                         0               0
FLASHBACK LOG                         0                         0               0
FOREIGN ARCHIVED LOG                  0                         0               0

7 rows selected.

· FRA에 자동으로 Backup 되는지 확인
[oracle@test ~]$ rman target /

Recovery Manager: Release 11.2.0.3.0 - Production on Tue Jul 13 16:55:08 2021

Copyright (c) 1982, 2011, Oracle and/or its affiliates.  All rights reserved.

connected to target database: UPTEST (DBID=xxxxxxxxx)

RMAN> backup database;

Starting backup at 13-JUL-21
using target database control file instead of recovery catalog
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=35 device type=DISK
channel ORA_DISK_1: starting full datafile backup set
channel ORA_DISK_1: specifying datafile(s) in backup set
input datafile file number=00001 name=/oracle/app/base/uptest/system01.dbf
input datafile file number=00002 name=/oracle/app/base/uptest/sysaux01.dbf
input datafile file number=00005 name=/oracle/app/base/uptest/test01.dbf
input datafile file number=00003 name=/oracle/app/base/uptest/undotbs01.dbf
input datafile file number=00004 name=/oracle/app/base/uptest/users01.dbf
channel ORA_DISK_1: starting piece 1 at 13-JUL-21
channel ORA_DISK_1: finished piece 1 at 13-JUL-21
piece handle=/oracle/fra/UPTEST/backupset/2021_07_13/o1_mf_nnndf_TAG20210713T165512_jgtkq07g_.bkp tag=TAG20210713T165512 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:07
channel ORA_DISK_1: starting full datafile backup set
channel ORA_DISK_1: specifying datafile(s) in backup set
including current control file in backup set
including current SPFILE in backup set
channel ORA_DISK_1: starting piece 1 at 13-JUL-21
channel ORA_DISK_1: finished piece 1 at 13-JUL-21
piece handle=/oracle/fra/UPTEST/backupset/2021_07_13/o1_mf_ncsnf_TAG20210713T165512_jgtkq8b5_.bkp tag=TAG20210713T165512 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:01
Finished backup at 13-JUL-21

[oracle@test ~]$ ls /oracle/fra/UPTEST/backupset/2021_07_13/
o1_mf_ncsnf_TAG20210713T165512_jgtkq8b5_.bkp  o1_mf_nnndf_TAG20210713T165512_jgtkq07g_.bkp

SQL> select * from v$recovery_area_usage;

FILE_TYPE            PERCENT_SPACE_USED PERCENT_SPACE_RECLAIMABLE NUMBER_OF_FILES
-------------------- ------------------ ------------------------- ---------------
CONTROL FILE                          0                         0               0
REDO LOG                              0                         0               0
ARCHIVED LOG                          0                         0               0
BACKUP PIECE                      14.22                         0               2
IMAGE COPY                            0                         0               0
FLASHBACK LOG                         0                         0               0
FOREIGN ARCHIVED LOG                  0                         0               0

7 rows selected.

 

 

 

참조 :

https://docs.oracle.com/database/121/ADMQS/GUID-EA0666F4-0EB0-4EB5-AD4C-24F77A64CE9D.htm#ADMQS09113

Fast Recovery Area

 

https://docs.oracle.com/database/121/ADMQS/GUID-D6A541BF-A878-4B45-AFAC-1E921554731E.htm#GUID-D6A541BF-A878-4B45-AFAC-1E921554731E

Configuring the Fast Recovery Area