QUESTION 8
Your multitenant container (CDB) containing three pluggable databases (PDBs) is running in ARCHIVELOG mode. You find that the SYSAUX tablespace is corrupted in the root container. The steps to recover the tablespace are as follows:
1. Mount the CDB.
2. Close all the PDBs.
3. Open the database.
4. Apply the archive redo logs.
5. Restore the data file.
6. Take the SYSAUX tablespace offline.
7. Place the SYSAUX tablespace online.
8. Open all the PDBs with RESETLOGS.
9. Open the database with RESETLOGS.
10. Execute the command SHUTDOWN ABORT.
Which option identifies the correct sequence to recover the SYSAUX tablespace?
A. 6,5,4,7
B. 10,1,2,5,8
C. 10,1,2,5,4,9,8
D. 10,1,5,8,10
【题目示意】
本题考察的是CDB中的SYSAUX表空间完全恢复。
【解析】
在数据库已经open的情况下,某些非关键数据文件发生损坏。只需要在保证数据库其他数据文件可用的状态下,对损坏的文件或损坏文件所在的表空间进行restore和recover操作。不需要关闭数据库,再进行恢复。在restore之前,要求表空间处于offline状态。
【实验】
1.修改数据库为归档模式
[[email protected] ~]$ sqlplus / as sysdba SQL*Plus: Release 12.1.0.1.0 Production on Mon Aug 11 14:58:41 2014 Copyright (c) 1982, 2013, Oracle. All rights reserved. Connected to an idle instance. [email protected]> startup ORACLE instance started. Total System Global Area 2121183232 bytes Fixed Size 2290360 bytes Variable Size 1308626248 bytes Database Buffers 805306368 bytes Redo Buffers 4960256 bytes Database mounted. Database opened. [email protected]> shu immediate Database closed. Database dismounted. ORACLE instance shut down. [email protected]> startup mount ORACLE instance started. Total System Global Area 2121183232 bytes Fixed Size 2290360 bytes Variable Size 1308626248 bytes Database Buffers 805306368 bytes Redo Buffers 4960256 bytes Database mounted. [email protected]> alter database archivelog; Database altered. [email protected]> alter database open; Database altered. [email protected]> alter system switch logfile; System altered.
2.使用RMAN备份数据库
[email protected]> !rman Recovery Manager: Release 12.1.0.1.0 - Production on Mon Aug 11 15:00:13 2014 Copyright (c) 1982, 2013, Oracle and/or its affiliates. All rights reserved. RMAN> connect target / connected to target database: DBSTYLE (DBID=2767578829) RMAN> backup database; Starting backup at 11-AUG-14 using target database control file instead of recovery catalog allocated channel: ORA_DISK_1 channel ORA_DISK_1: SID=50 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=00005 name=/u01/app/oracle/oradata/DBSTYLE/undotbs01.dbf input datafile file number=00001 name=/u01/app/oracle/oradata/DBSTYLE/system01.dbf input datafile file number=00003 name=/u01/app/oracle/oradata/DBSTYLE/sysaux01.dbf input datafile file number=00006 name=/u01/app/oracle/oradata/DBSTYLE/users01.dbf channel ORA_DISK_1: starting piece 1 at 11-AUG-14 channel ORA_DISK_1: finished piece 1 at 11-AUG-14 piece handle=/u01/app/oracle/fast_recovery_area/DBSTYLE/backupset/2014_08_11/o1_mf_nnndf_TAG20140811T150021_9yjtj5z5_.bkp tag=TAG20140811T150021 comment=NONE channel ORA_DISK_1: backup set complete, elapsed time: 00:00:26 channel ORA_DISK_1: starting full datafile backup set channel ORA_DISK_1: specifying datafile(s) in backup set input datafile file number=00008 name=/u01/app/oracle/oradata/DBSTYLE/DBS/sysaux01.dbf input datafile file number=00007 name=/u01/app/oracle/oradata/DBSTYLE/DBS/system01.dbf input datafile file number=00009 name=/u01/app/oracle/oradata/DBSTYLE/DBS/DBS_users01.dbf channel ORA_DISK_1: starting piece 1 at 11-AUG-14 channel ORA_DISK_1: finished piece 1 at 11-AUG-14 piece handle=/u01/app/oracle/fast_recovery_area/DBSTYLE/FDD32A078F321802E0430A50A8C0F4FF/backupset/2014_08_11/o1_mf_nnndf_TAG20140811T150021_9yjtjz65_.bkp tag=TAG20140811T150021 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 input datafile file number=00004 name=/u01/app/oracle/oradata/DBSTYLE/pdbseed/sysaux01.dbf input datafile file number=00002 name=/u01/app/oracle/oradata/DBSTYLE/pdbseed/system01.dbf channel ORA_DISK_1: starting piece 1 at 11-AUG-14 channel ORA_DISK_1: finished piece 1 at 11-AUG-14 piece handle=/u01/app/oracle/fast_recovery_area/DBSTYLE/FDD22BF463BC0F53E0430A50A8C0EDD2/backupset/2014_08_11/o1_mf_nnndf_TAG20140811T150021_9yjtk68h_.bkp tag=TAG20140811T150021 comment=NONE channel ORA_DISK_1: backup set complete, elapsed time: 00:00:07 Finished backup at 11-AUG-14 Starting Control File and SPFILE Autobackup at 11-AUG-14 piece handle=/u01/app/oracle/fast_recovery_area/DBSTYLE/autobackup/2014_08_11/o1_mf_s_855327661_9yjtkff8_.bkp comment=NONE Finished Control File and SPFILE Autobackup at 11-AUG-14 RMAN> list backup; List of Backup Sets =================== BS Key Type LV Size Device Type Elapsed Time Completion Time ------- ---- -- ---------- ----------- ------------ --------------- 1 Full 2.09G DISK 00:00:16 11-AUG-14 BP Key: 1 Status: AVAILABLE Compressed: NO Tag: TAG20140811T150021 Piece Name: /u01/app/oracle/fast_recovery_area/DBSTYLE/backupset/2014_08_11/o1_mf_nnndf_TAG20140811T150021_9yjtj5z5_.bkp List of Datafiles in backup set 1 File LV Type Ckp SCN Ckp Time Name ---- -- ---- ---------- --------- ---- 1 Full 1564193 11-AUG-14 /u01/app/oracle/oradata/DBSTYLE/system01.dbf 3 Full 1564193 11-AUG-14 /u01/app/oracle/oradata/DBSTYLE/sysaux01.dbf 5 Full 1564193 11-AUG-14 /u01/app/oracle/oradata/DBSTYLE/undotbs01.dbf 6 Full 1564193 11-AUG-14 /u01/app/oracle/oradata/DBSTYLE/users01.dbf BS Key Type LV Size Device Type Elapsed Time Completion Time ------- ---- -- ---------- ----------- ------------ --------------- 2 Full 762.73M DISK 00:00:04 11-AUG-14 BP Key: 2 Status: AVAILABLE Compressed: NO Tag: TAG20140811T150021 Piece Name: /u01/app/oracle/fast_recovery_area/DBSTYLE/FDD32A078F321802E0430A50A8C0F4FF/backupset/2014_08_11/o1_mf_nnndf_TAG20140811T150021_9yjtjz65_.bkp List of Datafiles in backup set 2 Container ID: 3, PDB Name: DBS File LV Type Ckp SCN Ckp Time Name ---- -- ---- ---------- --------- ---- 7 Full 1563088 11-AUG-14 /u01/app/oracle/oradata/DBSTYLE/DBS/system01.dbf 8 Full 1563088 11-AUG-14 /u01/app/oracle/oradata/DBSTYLE/DBS/sysaux01.dbf 9 Full 1563088 11-AUG-14 /u01/app/oracle/oradata/DBSTYLE/DBS/DBS_users01.dbf BS Key Type LV Size Device Type Elapsed Time Completion Time ------- ---- -- ---------- ----------- ------------ --------------- 3 Full 761.49M DISK 00:00:04 11-AUG-14 BP Key: 3 Status: AVAILABLE Compressed: NO Tag: TAG20140811T150021 Piece Name: /u01/app/oracle/fast_recovery_area/DBSTYLE/FDD22BF463BC0F53E0430A50A8C0EDD2/backupset/2014_08_11/o1_mf_nnndf_TAG20140811T150021_9yjtk68h_.bkp List of Datafiles in backup set 3 Container ID: 2, PDB Name: PDB$SEED File LV Type Ckp SCN Ckp Time Name ---- -- ---- ---------- --------- ---- 2 Full 1539785 10-JUL-14 /u01/app/oracle/oradata/DBSTYLE/pdbseed/system01.dbf 4 Full 1539785 10-JUL-14 /u01/app/oracle/oradata/DBSTYLE/pdbseed/sysaux01.dbf BS Key Type LV Size Device Type Elapsed Time Completion Time ------- ---- -- ---------- ----------- ------------ --------------- 4 Full 17.20M DISK 00:00:00 11-AUG-14 BP Key: 4 Status: AVAILABLE Compressed: NO Tag: TAG20140811T150101 Piece Name: /u01/app/oracle/fast_recovery_area/DBSTYLE/autobackup/2014_08_11/o1_mf_s_855327661_9yjtkff8_.bkp SPFILE Included: Modification time: 11-AUG-14 SPFILE db_unique_name: DBSTYLE Control File Included: Ckp SCN: 1565204 Ckp time: 11-AUG-14
3.删除sysaux01.dbf数据文件,模拟sysaux表空间损坏
[[email protected] DBSTYLE]$ rm -f sysaux01.dbf
4.使用RMAN进行restore操作,此时由于表空间没有离线,因此无法进行restore
RMAN> restore tablespace sysaux; Starting restore at 11-AUG-14 using channel ORA_DISK_1 channel ORA_DISK_1: starting datafile backup set restore channel ORA_DISK_1: specifying datafile(s) to restore from backup set channel ORA_DISK_1: restoring datafile 00003 to /u01/app/oracle/oradata/DBSTYLE/sysaux01.dbf channel ORA_DISK_1: reading from backup piece /u01/app/oracle/fast_recovery_area/DBSTYLE/backupset/2014_08_11/o1_mf_nnndf_TAG20140811T150021_9yjtj5z5_.bkp RMAN-00571: =========================================================== RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS =============== RMAN-00571: =========================================================== RMAN-03002: failure of restore command at 08/11/2014 15:18:45 ORA-19870: error while restoring backup piece /u01/app/oracle/fast_recovery_area/DBSTYLE/backupset/2014_08_11/o1_mf_nnndf_TAG20140811T150021_9yjtj5z5_.bkp ORA-19573: cannot obtain exclusive enqueue for datafile 3
5.将SYSAUX表空间离线,此时需要使用offline immediate命令
[[email protected] ~]$ sqlplus / as sysdba SQL*Plus: Release 12.1.0.1.0 Production on Mon Aug 11 15:01:27 2014 Copyright (c) 1982, 2013, Oracle. All rights reserved. Connected to: Oracle Database 12c Enterprise Edition Release 12.1.0.1.0 - 64bit Production With the Partitioning, Oracle Label Security, OLAP, Advanced Analytics and Real Application Testing options [email protected]> alter tablespace sysaux offline; alter tablespace sysaux offline * ERROR at line 1: ORA-01116: error in opening database file 3 ORA-01110: data file 3: ‘/u01/app/oracle/oradata/DBSTYLE/sysaux01.dbf‘ ORA-27041: unable to open file Linux-x86_64 Error: 2: No such file or directory Additional information: 3 [email protected]> alter tablespace sysaux offline immediate; Tablespace altered. [email protected]> select tablespace_name,status from dba_tablespaces; TABLESPACE_NAME STATUS ------------------------------ --------- SYSTEM ONLINE SYSAUX OFFLINE UNDOTBS1 ONLINE TEMP ONLINE USERS ONLINE
6.再次使用RMAN恢复表空间
RMAN> restore tablespace sysaux; Starting restore at 11-AUG-14 using channel ORA_DISK_1 channel ORA_DISK_1: starting datafile backup set restore channel ORA_DISK_1: specifying datafile(s) to restore from backup set channel ORA_DISK_1: restoring datafile 00003 to /u01/app/oracle/oradata/DBSTYLE/sysaux01.dbf channel ORA_DISK_1: reading from backup piece /u01/app/oracle/fast_recovery_area/DBSTYLE/backupset/2014_08_11/o1_mf_nnndf_TAG20140811T150021_9yjtj5z5_.bkp channel ORA_DISK_1: piece handle=/u01/app/oracle/fast_recovery_area/DBSTYLE/backupset/2014_08_11/o1_mf_nnndf_TAG20140811T150021_9yjtj5z5_.bkp tag=TAG20140811T150021 channel ORA_DISK_1: restored backup piece 1 channel ORA_DISK_1: restore complete, elapsed time: 00:00:07 Finished restore at 11-AUG-14 RMAN> recover tablespace sysaux; Starting recover at 11-AUG-14 using channel ORA_DISK_1 starting media recovery media recovery complete, elapsed time: 00:00:00 Finished recover at 11-AUG-14 RMAN> alter tablespace sysaux online; Statement processed RMAN>
7.SYSAUX表空间恢复正常
[email protected]> select tablespace_name,status from dba_tablespaces; TABLESPACE_NAME STATUS ------------------------------ --------- SYSTEM ONLINE SYSAUX ONLINE UNDOTBS1 ONLINE TEMP ONLINE USERS ONLINE [email protected]>
【小结】
无论CDB或者PDB,如果是非关键表空间发生损坏,对数据库影响最小的处理方法就是,让损坏的表空间离线,然后进行restore和recovery,进而使表空间恢复正常。因此A选项最合理。
【答案】 A
相关参考
http://docs.oracle.com/database/121/BRADV/rcmcomre.htm#BRADV89773
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【12C考题精解】OCP 1z0-060 QUESTION 8: Recovery of a Tablespace in the CDB