oracle日志文件和控制文件损坏的恢复 恢复步骤： 1.加入_allow_resetlogs_corruption=true，_corrupted_rollback_segments=true，_offline_rollback_segments=true，启动到nomount 2.利用控制文件的备份，进行脚本重建，由于current状态redo损坏，所以要reset

oracle日志文件和控制文件损坏的恢复　　恢复步骤：

1.加入_allow_resetlogs_corruption=true，_corrupted_rollback_segments=true，_offline_rollback_segments=true，启动到nomount

2.利用控制文件的备份，进行脚本重建，由于current状态redo损坏，所以要resetlogs重建

3.重建后通过alter database open resetlogs;打开数据库，这种情况会丢失在redo中相关事务的数据

备份控制文件并模拟故障：

SQL> set linesize 150

SQL> alter database backup controlfile to trace as '/home/oracle/ctl.ctl' reuse;

Database altered.

SQL> insert into tb1 values (1);

1 row created.

SQL> COMMIT;

Commit complete.

SQL> select * from v$log;

GROUP#    THREAD#  SEQUENCE#      BYTES    MEMBERS ARC STATUS           FIRST_CHANGE# FIRST_TIME

---------- ---------- ---------- ---------- ---------- --- ---------------- ------------- -------------------

1          1          1  536870912          1 YES INACTIVE            1.2269E+11 2013-05-03 16:08:03

2          1          2  536870912          1 YES INACTIVE            1.2269E+11 2013-05-03 16:23:48

3          1          3  536870912          1 NO  CURRENT             1.2269E+11 2013-05-11 07:26:45

4          1          0  536870912          1 YES UNUSED                       0

5          1          0  536870912          1 YES UNUSED                       0

SQL> shutdown abort;

oracle@readerlogdb-> rm -f redo03.log

oracle@readerlogdb-> rm -f control01.ctl control02.ctl control03.ctl

通过加入相关参数启动到nomount状态：

SQL> conn /as sysdba

Connected to an idle instance.

SQL> startup;

ORACLE instance started.

Total System Global Area 5049942016 bytes

Fixed Size                  2090880 bytes

Variable Size            1375733888 bytes

Database Buffers         3657433088 bytes

Redo Buffers               14684160 bytes

ORA-00205: error in identifying control file, check alert log for more info

SQL> create pfile='/home/oracle/pfile.ora' from spfile;

在备份的pfile中加入以下三行：

*._allow_resetlogs_corruption=true

*._corrupted_rollback_segments=true

*._offline_rollback_segments=true

NORESETLOGS和RESETLOGS在此实验中的区别：

SQL>CREATE CONTROLFILE REUSE DATABASE "SKYREAD" NORESETLOGS FORCE LOGGING ARCHIVELOG

MAXLOGFILES 20

MAXLOGMEMBERS 5

MAXDATAFILES 1000

MAXINSTANCES 8

MAXLOGHISTORY 2337

LOGFILE

GROUP 1 '/database/oradata/skyread/redo01.log'  SIZE 512M,

GROUP 2 '/database/oradata/skyread/redo02.log'  SIZE 512M,

GROUP 3 '/database/oradata/skyread/redo03.log'  SIZE 512M,

GROUP 4 '/database/oradata/skyread/redo04.log'  SIZE 512M,

GROUP 5 '/database/oradata/skyread/redo05.log'  SIZE 512M

DATAFILE