首页 > 代码库 > Backup Optimization for SBT Backups With Redundancy Retention Policy
Backup Optimization for SBT Backups With Redundancy Retention Policy
ocp 053
703. Given below are RMAN commands to enable ba ckup optimization and set the retention policy:
The USERS tablespace has never been backed up. Y ou take the USERS tablespace offline on Monday.
View the Exhibit to examine the operations performed by using RMAN. Which two statements are true
about the backup of the USERS tablespace? (Choose two.)
A.It will be backed up as a part of database backup on Friday.
B.It will be backed up as a part of database backup on Tuesday.
C.It will not be backed up as a part of database backup on Wednesday.
D.The command on Sunday deletes the backup of the USERS tablespace taken on Tuesday.
Answer: AB
答案解析:
从以下答案指导BD正确。
参考:http://docs.oracle.com/cd/E11882_01/backup.112/e10642/rcmconfb.htm#BRADV89464
Backup Optimization for SBT Backups With Redundancy Retention Policy
Assume that you configure a retention policy for redundancy. In this case, RMAN only skips backups of offline or read-only data files to SBT when there are r
+ 1 backups of the files, where r
is set in CONFIGURE
RETENTION
POLICY
TO
REDUNDANCY
r
.
For example, assume that you enable backup optimization and set the following retention policy:
With these settings, RMAN only skips backups when three identical files are already backed up. Also assume that you have never backed up the users
tablespace, which is read/write, and that you perform the actions described in Table 5-5 over the course of the week.
Table 5-5 Effect of Redundancy Setting on Backup Optimization
Day | Action | Result | Redundant Backup |
---|---|---|---|
Monday | Take | ||
Tuesday |
| The | |
Wednesday |
| The | |
Thursday |
| The | Tuesday backup |
Friday |
| The | Tuesday backup |
Saturday |
| The | Tuesday backup |
Sunday |
| The Tuesday backup is deleted. | |
Monday |
| The | Wednesday backup |
The backups on Tuesday, Wednesday, and Thursday back up the offline users
tablespace to satisfy the condition that three backups must exist (one more than redundancy setting). The Friday and Saturday backups do not back up the users
tablespace because of backup optimization. The Tuesday backup of users
is obsolete beginning on Thursday.
On Sunday, you delete all obsolete backups, which removes the Tuesday backup of users
. The Tuesday backup is obsolete because of the retention policy setting. The whole database backup on Monday then backs up the users
tablespace to satisfy the condition that three backups must exist (one more than redundancy setting). In this way, you can recycle your tapes over time.
RMAN> show all;
RMAN configuration parameters for database with db_unique_name TEST0221 are:
CONFIGURE RETENTION POLICY TO REDUNDANCY 2;
CONFIGURE BACKUP OPTIMIZATION ON;
CONFIGURE DEFAULT DEVICE TYPE TO DISK; # default
CONFIGURE CONTROLFILE AUTOBACKUP OFF; # default
CONFIGURE CONTROLFILE AUTOBACKUP FORMAT FOR DEVICE TYPE DISK TO ‘%F‘; # default
CONFIGURE DEVICE TYPE DISK PARALLELISM 1 BACKUP TYPE TO BACKUPSET; # default
CONFIGURE DATAFILE BACKUP COPIES FOR DEVICE TYPE DISK TO 1; # default
CONFIGURE ARCHIVELOG BACKUP COPIES FOR DEVICE TYPE DISK TO 1; # default
CONFIGURE MAXSETSIZE TO UNLIMITED; # default
CONFIGURE ENCRYPTION FOR DATABASE OFF; # default
CONFIGURE ENCRYPTION ALGORITHM ‘AES128‘; # default
CONFIGURE COMPRESSION ALGORITHM ‘BASIC‘ AS OF RELEASE ‘DEFAULT‘ OPTIMIZE FOR LOAD TRUE ; # default
CONFIGURE ARCHIVELOG DELETION POLICY TO NONE; # default
CONFIGURE SNAPSHOT CONTROLFILE NAME TO ‘/u01/app/oracle/product/11.2.0/dbhome_1/dbs/snapcf_test0221.f‘; # default
RMAN> list backup;
specification does not match any backup in the repository
RMAN> sql ‘alter tablespace users offline‘;----------星期一offline
sql statement: alter tablespace users offline
RMAN> backup database; -----------------星期二,全库备份
Starting backup at 06-MAR-14
using channel ORA_DISK_1
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=/u01/app/oracle/oradata/test0221/system01.dbf
input datafile file number=00002 name=/u01/app/oracle/oradata/test0221/sysaux01.dbf
input datafile file number=00005 name=/u01/app/oracle/oradata/test0221/example01.dbf
input datafile file number=00003 name=/u01/app/oracle/oradata/test0221/undotbs01.dbf
input datafile file number=00004 name=/u01/app/oracle/oradata/test0221/users01.dbf
channel ORA_DISK_1: starting piece 1 at 06-MAR-14
channel ORA_DISK_1: finished piece 1 at 06-MAR-14
piece handle=/u01/app/oracle/fast_recovery_area/TEST0221/backupset/2014_03_06/o1_mf_nnndf_TAG20140306T123613_9khysyg0_.bkp tag=TAG20140306T123613 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:01:55
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 06-MAR-14
channel ORA_DISK_1: finished piece 1 at 06-MAR-14
piece handle=/u01/app/oracle/fast_recovery_area/TEST0221/backupset/2014_03_06/o1_mf_ncsnf_TAG20140306T123613_9khyxm0v_.bkp tag=TAG20140306T123613 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:02
Finished backup at 06-MAR-14
RMAN> backup database;----------星期三全库备份
Starting backup at 06-MAR-14
using channel ORA_DISK_1
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=/u01/app/oracle/oradata/test0221/system01.dbf
input datafile file number=00002 name=/u01/app/oracle/oradata/test0221/sysaux01.dbf
input datafile file number=00005 name=/u01/app/oracle/oradata/test0221/example01.dbf
input datafile file number=00003 name=/u01/app/oracle/oradata/test0221/undotbs01.dbf
input datafile file number=00004 name=/u01/app/oracle/oradata/test0221/users01.dbf
channel ORA_DISK_1: starting piece 1 at 06-MAR-14
channel ORA_DISK_1: finished piece 1 at 06-MAR-14
piece handle=/u01/app/oracle/fast_recovery_area/TEST0221/backupset/2014_03_06/o1_mf_nnndf_TAG20140306T123854_9khyyyqz_.bkp tag=TAG20140306T123854 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:01:56
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 06-MAR-14
channel ORA_DISK_1: finished piece 1 at 06-MAR-14
piece handle=/u01/app/oracle/fast_recovery_area/TEST0221/backupset/2014_03_06/o1_mf_ncsnf_TAG20140306T123854_9khz2mf1_.bkp tag=TAG20140306T123854 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:01
Finished backup at 06-MAR-14