Oracle控制文件多路复用以及Oracle备份重建控制文件

控制文件中记录了oracle数据库的物理结构，也就是记录了数据库数据文件和日志文件的位置，控制文件中还记录了多种SCN，用这些SCN来确定数据文件和日志文件是否是正确的。如果不正确那么数据库就需要恢复
启动数据库有三个状态
nomount 加载参数文件启动实例
mount 加载控制文件
open 根据控制文件加载数据文件和日志文件

一、Oracle控制文件多路复用

查询控制文件路径

SYS@zwcdb:~>SELECT name FROM v$controlfile;

NAME

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

/u01/app/oracle/oradata/primarydb/control01.ctl

/u01/app/oracle/oradata/primarydb/control02.ctl

/u01/app/oracle/oradata/primarydb/control03.ctl

修改spfile

SYS@zwcdb:~>ALTER system SET control_files=

2 '/u01/app/oracle/oradata/primarydb/control01.ctl',

3 '/u01/app/oracle/oradata/primarydb/control02.ctl',

4 '/u01/app/oracle/oradata/primarydb/control03.ctl',

5 '/u01/app/control04.ctl' scope=spfile;

System altered.

关闭数据库,复制控制文件至/u01/app下

SYS@zwcdb:~>shutdown immediate

DATABASE closed.

DATABASE dismounted.

ORACLE instance shut down.

SYS@zwcdb:~>exit

Disconnected FROM Oracle DATABASE 10g Enterprise Edition Release 10.2.0.1.0 - Production

WITH the Partitioning, OLAP AND DATA Mining options

[oracle@zwc ~]$ cp /u01/app/oracle/oradata/primarydb/control01.ctl /u01/app/control04.ctl

重新启动数据库并验证

[oracle@zwc ~]$ sqlplus / AS sysdba

SQL*Plus: Release 10.2.0.1.0 - Production ON Fri Jan 6 10:35:05 2012

Connected TO an idle instance.

SYS@zwcdb:~>startup

ORACLE instance started.

Total System Global Area 285212672 bytes

Fixed SIZE 1218992 bytes

Variable SIZE 92276304 bytes

DATABASE Buffers 188743680 bytes

Redo Buffers 2973696 bytes

DATABASE mounted.

DATABASE opened.

SYS@zwcdb:~>

SYS@zwcdb:~>SELECT name FROM v$controlfile;

NAME

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

/u01/app/oracle/oradata/primarydb/control01.ctl

/u01/app/oracle/oradata/primarydb/control02.ctl

/u01/app/oracle/oradata/primarydb/control03.ctl

/u01/app/control04.ctl

SYS@zwcdb:~>SELECT VALUE FROM v$spparameter WHERE name='control_files';

VALUE

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

/u01/app/oracle/oradata/primarydb/control01.ctl

/u01/app/oracle/oradata/primarydb/control02.ctl

/u01/app/oracle/oradata/primarydb/control03.ctl

/u01/app/control04.ctl

二、Oracle备份重建控制文件

建议在数据文件或者日志文件发生变化时对控制文件进行备份,在这之前备份的控制文件会被标记为已过时。可以使用alter database bacup controlfile命令进行备份,备份方式有两种,一种是备份为二进制文件;另一种是备份为脚本文件

将控制文件备份到二进制文件

SYS@zwcdb:~>alter database backup controlfile to '/u01/app/control.bak.ctl';

Database altered.

SYS@zwcdb:~>!ls -lh /u01/app/control*

-rw-r----- 1 oracle oinstall 6.8M Jan 6 10:52 /u01/app/control04.ctl

-rw-r----- 1 oracle oinstall 6.8M Jan 6 10:51 /u01/app/control.bak.ctl

控制文件转储为脚本

SYS@zwcdb:~>oradebug setmypid

Statement processed.

SYS@zwcdb:~>ALTER DATABASE backup controlfile TO trace;

DATABASE altered.

SYS@zwcdb:~>oradebug tracefile_name

/u01/app/oracle/admin/primarydb/udump/zwcdb_ora_3401.trc

查看zwcdb_ora_3401.trc文件内容会发现以下两段脚本,区别在于第一段是noresetlogs,第二段是resetlogs。这里日志组不需要重建,所以将使用noresetlogs
MAXLOGFILES 16 表示最大日志文件个数为16
MAXLOGMEMBERS 3 表示日志文件组的成员是3个
MAXDATAFILES 100 表示最大的数据文件个数是100
MAXINSTANCES 8 表示最大实例个数是8
MAXLOGHISTORY 292 表示最大的历史日志文件个数是292

CREATE CONTROLFILE REUSE DATABASE "ZWCDB" NORESETLOGS ARCHIVELOG

MAXLOGFILES 16

MAXLOGMEMBERS 3

MAXDATAFILES 100

MAXINSTANCES 8

MAXLOGHISTORY 292

LOGFILE

GROUP 1 '/u01/app/oracle/oradata/primarydb/redo01.log' SIZE 50M,

GROUP 2 '/u01/app/oracle/oradata/primarydb/redo02.log' SIZE 50M,

GROUP 3 '/u01/app/oracle/oradata/primarydb/redo03.log' SIZE 50M

-- STANDBY LOGFILE

DATAFILE

'/u01/app/oracle/oradata/primarydb/system01.dbf',

'/u01/app/oracle/oradata/primarydb/undotbs01.dbf',

'/u01/app/oracle/oradata/primarydb/sysaux01.dbf',

'/u01/app/oracle/oradata/primarydb/users01.dbf',

'/u01/app/oracle/oradata/primarydb/example01.dbf'

CHARACTER SET ZHS16GBK

;

resetlogs

CREATE CONTROLFILE REUSE DATABASE "ZWCDB" RESETLOGS ARCHIVELOG

MAXLOGFILES 16

MAXLOGMEMBERS 3

MAXDATAFILES 100

MAXINSTANCES 8

MAXLOGHISTORY 292

LOGFILE

GROUP 1 '/u01/app/oracle/oradata/primarydb/redo01.log' SIZE 50M,

GROUP 2 '/u01/app/oracle/oradata/primarydb/redo02.log' SIZE 50M,

GROUP 3 '/u01/app/oracle/oradata/primarydb/redo03.log' SIZE 50M

-- STANDBY LOGFILE

DATAFILE

'/u01/app/oracle/oradata/primarydb/system01.dbf',

'/u01/app/oracle/oradata/primarydb/undotbs01.dbf',

'/u01/app/oracle/oradata/primarydb/sysaux01.dbf',

'/u01/app/oracle/oradata/primarydb/users01.dbf',

'/u01/app/oracle/oradata/primarydb/example01.dbf'

CHARACTER SET ZHS16GBK

;

模拟控制文件丢失

[oracle@zwc app]$ rm -rf control04.ctl

[oracle@zwc app]$ rm -rf /u01/app/oracle/oradata/primarydb/control0*

[oracle@zwc app]$ sqlplus / AS sysdba

SQL*Plus: Release 10.2.0.1.0 - Production ON Fri Jan 6 11:02:55 2012

Connected TO:

Oracle DATABASE 10g Enterprise Edition Release 10.2.0.1.0 - Production

WITH the Partitioning, OLAP AND DATA Mining options

SYS@zwcdb:~>shutdown abort

ORACLE instance shut down.

重建控制文件

[oracle@zwc app]$ sqlplus / AS sysdba

SQL*Plus: Release 10.2.0.1.0 - Production ON Fri Jan 6 11:07:00 2012

Connected TO an idle instance.

SYS@zwcdb:~>startup nomount

ORACLE instance started.

Total System Global Area 285212672 bytes

Fixed SIZE 1218992 bytes

Variable SIZE 92276304 bytes

DATABASE Buffers 188743680 bytes

Redo Buffers 2973696 bytes

SYS@zwcdb:~>CREATE CONTROLFILE REUSE DATABASE "ZWCDB" NORESETLOGS ARCHIVELOG

2 MAXLOGFILES 16

3 MAXLOGMEMBERS 3

4 MAXDATAFILES 100

5 MAXINSTANCES 8

6 MAXLOGHISTORY 292

7 LOGFILE

8 GROUP 1 '/u01/app/oracle/oradata/primarydb/redo01.log' SIZE 50M,

9 GROUP 2 '/u01/app/oracle/oradata/primarydb/redo02.log' SIZE 50M,

10 GROUP 3 '/u01/app/oracle/oradata/primarydb/redo03.log' SIZE 50M

11 DATAFILE

12 '/u01/app/oracle/oradata/primarydb/system01.dbf',

13 '/u01/app/oracle/oradata/primarydb/undotbs01.dbf',

14 '/u01/app/oracle/oradata/primarydb/sysaux01.dbf',

15 '/u01/app/oracle/oradata/primarydb/users01.dbf',

16 '/u01/app/oracle/oradata/primarydb/example01.dbf'

17 CHARACTER SET ZHS16GBK

18 ;

Control file created.

SYS@zwcdb:~>RECOVER DATABASE;

Media recovery complete.

SYS@zwcdb:~>ALTER SYSTEM ARCHIVE LOG ALL;

System altered.

SYS@zwcdb:~>ALTER DATABASE OPEN;

DATABASE altered.

SYS@zwcdb:~>ALTER TABLESPACE TEMP ADD TEMPFILE '/u01/app/oracle/oradata/primarydb/temp01.dbf'

2 SIZE 20971520 REUSE AUTOEXTEND ON NEXT 655360 MAXSIZE 32767M;

Tablespace altered.

[oracle@zwc ~]$ sqlplus / AS sysdba

SQL*Plus: Release 10.2.0.1.0 - Production ON Fri Jan 6 11:12:42 2012

Connected TO:

Oracle DATABASE 10g Enterprise Edition Release 10.2.0.1.0 - Production

WITH the Partitioning, OLAP AND DATA Mining options

SYS@zwcdb:~>SELECT open_mode,log_mode FROM v$database;

OPEN_MODE LOG_MODE

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

READ WRITE ARCHIVELOG

SYS@zwcdb:~>SELECT name FROM v$controlfile;

NAME

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

/u01/app/oracle/oradata/primarydb/control01.ctl

/u01/app/oracle/oradata/primarydb/control02.ctl

/u01/app/oracle/oradata/primarydb/control03.ctl

/u01/app/control04.ctl

SYS@zwcdb:~>!ls /u01/app/control*

/u01/app/control04.ctl /u01/app/control.bak.ctl

SYS@zwcdb:~>!ls $ORACLE_BASE/oradata/primarydb/con*

/u01/app/oracle/oradata/primarydb/control01.ctl /u01/app/oracle/oradata/primarydb/control02.ctl /u01/app/oracle/oradata/primarydb/control03.ctl

SYS@zwcdb:~>conn scott/tiger@zwcdb

Connected.

SCOTT@zwcdb:~>SELECT tname FROM tab;

TNAME

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

DEPT

EMP

BONUS

SALGRADE