****控制文件作用：****记录了数据库的结构和行为，有多少个数据文件，日志文件及其位置名称，状态，维护数据库的一致性，即记录了数据库的启动SCN号和终止SCN号。
控制文件的位置和个数记录在参数文件中，通常控制文件采用多路复用的方式来存放管理，一个数据库中最多有8个控制文件，超过了不行，至少不行，默认创建数据库有3个控制文件。启动时由参数文件记录顺序决定控制文件使用顺序。
控制文件为二进制文件，一般不超过100m，数据库启动到mount阶段时读取控制文件内容，以后一直在用。控制文件记录了数据库名字，标示符，创建时间戳，表空间名字，日志文件名字，SCN号，归档备份信息、字符集等。
查找控制文件：
方法一：
SQL> show parameter control_file
NAME TYPE VALUE
control_file_record_keep_time integer 7
control_files string /u01/oracle/oradata/orcl/contr
ol01.ctl, /u01/oracle/oradata/
orcl/control02.ctl, /u01/oracl
e/oradata/orcl/control03.ctl
方法二：
SQL>col name for a29;
SQL>col value for a40;
SQL> select name,value from v$parameter where name like '%control_file%';
NAME VALUE
control_files /u01/oracle/oradata/orcl/control01.ctl,
/u01/oracle/oradata/orcl/control02.ctl,
/u01/oracle/oradata/orcl/control03.ctl
control_file_record_keep_time 7
方法三：
SQL> col name for a40;
SQL> select name,status from v$controlfile;
NAME STATUS
/u01/oracle/oradata/orcl/control01.ctl
/u01/oracle/oradata/orcl/control02.ctl
/u01/oracle/oradata/orcl/control03.ctl
查看控制文件记录内容：
方法一：
oracle@localhost \~\]$ strings /u01/oracle/oradata/orcl/control01.ctl
方法二：
SQL\> alter database backup controlfile to trace as '/u01/oracle/controlfile.txt';
Database altered.
SQL\> ho cat /u01/oracle/controlfile.txt
方法三：
SQL\> desc v$controlfile_record_section
Name Null? Type
----------------------------------------- -------- ----------------------------
TYPE VARCHAR2(28)
RECORD_SIZE NUMBER
RECORDS_TOTAL NUMBER
RECORDS_USED NUMBER
FIRST_INDEX NUMBER
LAST_INDEX NUMBER
LAST_RECID NUMBER
SQL\> select type,record_size from v$controlfile_record_section;
TYPE RECORD_SIZE
---------------------------- -----------
DATABASE 316
CKPT PROGRESS 8180
REDO THREAD 256
REDO LOG 72
DATAFILE 428
..........
方法三：转储控制文件内容
方法a：
SQL\> alter system set events 'immediate trace name controlf level 10';
System altered.
SQL\> show parameter user_d
NAME TYPE VALUE
------------------------------------ ----------- -----------------------------------------------------------------------
user_dump_dest string /u01/oracle/admin/orcl/udump
\[oracle@localhost \~\]$ ll /u01/oracle/admin/orcl/udump并查看最新的文件信息
\[oracle@localhost \~\]$ cat /u01/oracle/admin/orcl/udump/orcl_ora_29296.trc
方法b：
SQL\> oradebug setmypid
SQL\> select spid from v$process where addr=(select paddr from v$session where sid=(select sid from v$mystat where rownum=1));
SQL\> oradebug dump controlf 3
SQL\> show parameter user_d
SQL\> ho ls /u01/oracle/admin/orcl/udump/
\[oracle@localhost \~\]$ cat /u01/oracle/admin/orcl/udump/orcl_ora_3223.trc
方法三（11g新增）：
\[root@localhost \~\]# select value from v$diag_info where name='default trace file';
****控制文件管理：****
控制文件个数和位置的管理（多路复用）：
通过spfile修改控制文件个数及位置：
将控制文件减少到1个：
SQL\> alter system set control_files='/u01/oracle/oradata/orcl/control01.ctl' scope=spfile;
System altered.
SQL\> shutdown immediate
Database closed.
Database dismounted.
ORACLE instance shut down.
SQL\> startup
ORACLE instance started.
Total System Global Area 285212672 bytes
Fixed Size 1218968 bytes
Variable Size 83887720 bytes
Database Buffers 192937984 bytes
Redo Buffers 7168000 bytes
Database mounted.
Database opened.
SQL\> show parameter control_f
NAME TYPE VALUE
------------------------------------ ----------- -------------------------------------------------------------
control_file_record_keep_time integer 7
control_files string /u01/oracle/oradata/orcl/contr
将控制文件增加到3个：
SQL\> alter system set control_files='/u01/oracle/oradata/orcl/control01.ctl'
,'/u01/oracle/oradata/orcl/control02.ctl','/u01/oracle/oradata/orcl/control03.ctl' scope=spfile;
System altered.
SQL\> shutdown immediate
Database closed.
Database dismounted.
ORACLE instance shut down.
SQL\> startup
ORACLE instance started.
Total System Global Area 285212672 bytes
Fixed Size 1218968 bytes
Variable Size 83887720 bytes
Database Buffers 192937984 bytes
Redo Buffers 7168000 bytes
ORA-00214: control file '/u01/oracle/oradata/orcl/control01.ctl' version 677
inconsistent with file '/u01/oracle/oradata/orcl/control02.ctl' version 668
可以看到重启数据库报错version不一致，此时应该把高版本的copy给低版本即可：
SQL\>exit
\[oracle@localhost orcl\]$ cp control01.ctl control02.ctl
\[oracle@localhost orcl\]$ cp control01.ctl control03.ctl
\[oracle@localhost orcl\]$ sqlplus / as sysdba
SQL\*Plus: Release 10.2.0.1.0 - Production on Sun Mar 15 19:29:56 2015
Copyright (c) 1982, 2005, Oracle. All rights reserved.
Connected to:
Oracle Database 10g Enterprise Edition Release 10.2.0.1.0 - Production
With the Partitioning, OLAP and Data Mining options
SQL\> startup force
ORACLE instance started.
Total System Global Area 285212672 bytes
Fixed Size 1218968 bytes
Variable Size 83887720 bytes
Database Buffers 192937984 bytes
Redo Buffers 7168000 bytes
Database mounted.
Database opened.
SQL\> show parameter control_f
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------------------------------------------------
control_file_record_keep_time integer 7
control_files string /u01/oracle/oradata/orcl/contr
ol01.ctl, /u01/oracle/oradata/
orcl/control02.ctl, /u01/oracl
e/oradata/orcl/control03.ctl
查看控制文件状态：查看控制文件是否存在、磁盘空间是否够用、控制文件大小是否超过100m
SQL\> show parameter control_f
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------------------------------------------------
control_file_record_keep_time integer 7
control_files string /u01/oracle/oradata/orcl/contr
ol01.ctl, /u01/oracle/oradata/
orcl/control02.ctl, /u01/oracl
e/oradata/orcl/control03.ctl
然后查看控制文件具体路径是否存在：
\[oracle@localhost orcl\]$ ls /u01/oracle/oradata/orcl/\*.ctl
/u01/oracle/oradata/orcl/control01.ctl
/u01/oracle/oradata/orcl/control02.ctl
/u01/oracle/oradata/orcl/control03.ctl
查看磁盘容量是否够用：
\[oracle@localhost orcl\]$ df -h
文件系统 容量 已用 可用 已用% 挂载点
/dev/mapper/VolGroup00-LogVol00
18G 11G 6.3G 62% /
/dev/sda1 99M 12M 82M 13% /boot
tmpfs 506M 0 506M 0% /dev/shm
查看控制文件大小：如果超过100m，需要重建控制文件
\[oracle@localhost orcl\]$ ls -l /u01/oracle/oradata/orcl/\*.ctl
-rw-r----- 1 oracle oinstall ****7061504**** 03-15 19:38 /u01/oracle/oradata/orcl/control01.ctl
-rw-r----- 1 oracle oinstall ****7061504**** 03-15 19:38 /u01/oracle/oradata/orcl/control02.ctl
-rw-r----- 1 oracle oinstall ****7061504**** 03-15 19:38 /u01/oracle/oradata/orcl/control03.ctl
****对控制文件的管理原则：****
1.明确控制文件的名称和存储路径
参数设置错误将无法打开数据库，数据库打开以后，实例将同时写入所有的控制文件但是只会读取第一个控制文件的内容。
2.为数据库创建多路控制文件
a.多路控制文件内容必须完全一样，oracle实例同时将内容写入到control_files变量所设置的控制文件中。
b.初始化参数control_files中列出的第一个文件是数据库运行期间唯一可读取的控制文件。
c.创建，恢复和备份控制文件必须在数据库关闭的状态下运行，这样才能保证操作过程中控制文件不被修改。
d.数据库运行期间如果一个控制文件变为不可用，那么实例将不再运行，应该终止这个实例，并对破坏的控制文件进行修复。
3.将多路控制文件放在不同的硬盘上
4.采用操作系统镜像方式备份控制文件
5.手工方式备份控制文件
应该及时备份特别是发生了如下的操作的时候：
添加删除重命名数据文件
添加删除表空间，改变表空间读写状态
添加删除重做日志文件
****控制文件备份:****
1）热备：
SQL\>alter database backup controlfile to '/u01/oracle/controlfile2015.bak';--\>归档备份
SQL\>alter database backup controlfile to trace as '/u01/oracle/controlfile2015.txt';
--\>归档非归档均可备份
2)rman备份
\[oracle@localhost orcl\]$ rman target /
Recovery Manager: Release 10.2.0.1.0 - Production on Sun Mar 15 19:56:47 2015
Copyright (c) 1982, 2005, Oracle. All rights reserved.
connected to target database: ORCL (DBID=1401907058)
****RMAN\> backup current controlfile;****
****RMAN\> backup database include current controlfile;****
3）设置控制文件自动备份
RMAN\> show all;
RMAN configuration parameters are:
CONFIGURE RETENTION POLICY TO REDUNDANCY 1; # default
CONFIGURE BACKUP OPTIMIZATION OFF; # default
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 ARCHIVELOG DELETION POLICY TO NONE; # default
CONFIGURE SNAPSHOT CONTROLFILE NAME TO '/u01/oracle/10g/dbs/snapcf_orcl.f'; # default
通过红色部分可以看出现在controlfile的自动备份是被off的，通过以下命令打开自动备份。
****RMAN\> CONFIGURE CONTROLFILE AUTOBACKUP**** ****ON**** ****;****
****恢复：****
1）控制文件不一致解决办法：
查看控制文件版本号，复制新的给旧的；
SQL\> startup
ORACLE instance started.
Total System Global Area 285212672 bytes
Fixed Size 1218968 bytes
Variable Size 83887720 bytes
Database Buffers 192937984 bytes
Redo Buffers 7168000 bytes
****ORA-00214: control file '/u01/oracle/oradata/orcl/control01.ctl' version 677****
****inconsistent with file '/u01/oracle/oradata/orcl/control02.ctl' version 668****
可以看到重启数据库报错version不一致，此时应该把高版本的copy给低版本即可：
SQL\>exit
\[oracle@localhost orcl\]$ cp control01.ctl control02.ctl
\[oracle@localhost orcl\]$ cp control01.ctl control03.ctl
\[oracle@localhost orcl\]$ sqlplus / as sysdba
SQL\*Plus: Release 10.2.0.1.0 - Production on Sun Mar 15 19:29:56 2015
Copyright (c) 1982, 2005, Oracle. All rights reserved.
Connected to:
Oracle Database 10g Enterprise Edition Release 10.2.0.1.0 - Production
With the Partitioning, OLAP and Data Mining options
SQL\> startup force
ORACLE instance started.
Total System Global Area 285212672 bytes
Fixed Size 1218968 bytes
Variable Size 83887720 bytes
Database Buffers 192937984 bytes
Redo Buffers 7168000 bytes
Database mounted.
Database opened.
SQL\>
修改spfile使用最新的控制文件。
SQL\> startup
ORACLE instance started.
Total System Global Area 285212672 bytes
Fixed Size 1218968 bytes
Variable Size 83887720 bytes
Database Buffers 192937984 bytes
Redo Buffers 7168000 bytes
ORA-00214: control file '/u01/oracle/oradata/orcl/control01.ctl' version 677
inconsistent with file '/u01/oracle/oradata/orcl/control02.ctl' version 668
通过以上错误，我们看到了控制文件版本号，不一致，所以修改参数文件使用最新的版本号：
SQL\> alter system set control_files='/u01/oracle/oradata/orcl/control01.ctl' scope=spfile;
System altered.
SQL\> shutdown immediate
Database closed.
Database dismounted.
ORACLE instance shut down.
SQL\> startup
ORACLE instance started.
Total System Global Area 285212672 bytes
Fixed Size 1218968 bytes
Variable Size 83887720 bytes
Database Buffers 192937984 bytes
Redo Buffers 7168000 bytes
Database mounted.
Database opened.
2）控制文件丢失有备份恢复方法
A、非归档、有全备需要重建控制文件。
SQL\> startup
ORACLE instance started.
Total System Global Area 285212672 bytes
Fixed Size 1218968 bytes
Variable Size 83887720 bytes
Database Buffers 192937984 bytes
Redo Buffers 7168000 bytes
****ORA-00205: error in identifying control file, check alert log for more info****
通过查看警告日志alert_orc.log， control04.ctl丢失，内容如下：
\[oracle@localhost \~\]$ vi /u01/oracle/admin/orcl/bdump/alert_orcl.log
4051 Sun Mar 15 20:46:44 2015
4052 ORA-00202: control file: '/u01/oracle/oradata/orcl/control04.ctl'
4053 ORA-27037: unable to obtain file status
4054 Linux Error: 2: No such file or directory
4055 Additional information: 3
4056 Sun Mar 15 20:46:47 2015
4057 ORA-205 signalled during: ALTER DATABASE MOUNT...
解决方法：1）如果存在多个控制文件，只丢失了其中一个控制文件，把存在的copy给丢失的即可解决。
2）如果所有控制文件都丢失了，重建数据库（最惨情况），可以通过控制文件转储文件或跟踪文件查看内容，恢复内容。
SQL\> create controlfile reuse database orcl noarchivelog noresetlogs
2 maxlogfiles 16
3 maxinstances 8
4 maxlogmembers 3
5 maxloghistory 1
6 logfile
7 group 1 '/u01/oracle/oradata/orcl/redo01.log' size 50m,
8 group 2 '/u01/oracle/oradata/orcl/redo02.log' size 50m,
9 group 3 '/u01/oracle/oradata/orcl/redo03.log' size 50m
10 datafile
11 '/u01/oracle/oradata/orcl/example01.dbf',
....................
12 charecter set utf8
SQL\>alter database open;
恢复数据库：SQL\>recover database;
B、归档，有备份，控制文件丢失恢复
如果数据库不是归档模式，首先将数据库改为归档模式，方法如下：
SQL\> archive log list
Database log mode No Archive Mode
Automatic archival Disabled
Archive destination USE_DB_RECOVERY_FILE_DEST
Oldest online log sequence 12
Current log sequence 14
SQL\> shutdown immediate
Database closed.
Database dismounted.
ORACLE instance shut down.
SQL\> startup mount
ORACLE instance started.
Total System Global Area 285212672 bytes
Fixed Size 1218968 bytes
Variable Size 83887720 bytes
Database Buffers 192937984 bytes
Redo Buffers 7168000 bytes
Database mounted.
SQL\> alter database archivelog;
Database altered.
备份控制文件：
SQL\> alter database backup controlfile to '/u01/oracle/ctl2015.ctl';
Database altered.
SQL\> startup
ORACLE instance started.
Total System Global Area 285212672 bytes
Fixed Size 1218968 bytes
Variable Size 88082024 bytes
Database Buffers 188743680 bytes
Redo Buffers 7168000 bytes
ORA-00205: error in identifying control file, check alert log for more info
通过查看alert_orcl.log文件可知control05.ctl文件丢失：
\[oracle@localhost \~\]$ vi /u01/oracle/admin/orcl/bdump/alert_orcl.log
ALTER DATABASE MOUNT
Mon Mar 16 07:55:45 2015
ORA-00202: control file: '/u01/oracle/oradata/orcl/control05.ctl'
ORA-27037: unable to obtain file status
Linux Error: 2: No such file or directory
Additional information: 3
Mon Mar 16 07:55:48 2015
ORA-205 signalled during: ALTER DATABASE MOUNT...
copy备份文件到指定文件：
SQL\> ho cp /u01/oracle/ctl2015.ctl /u01/oracle/oradata/orcl/control05.ctl
SQL\> alter database mount;
Database altered.
SQL\> alter database open;
alter database open
ERROR at line 1:
ORA-01589: must use RESETLOGS or NORESETLOGS option for database open
SQL\> alter database recover database using backup controlfile;
alter database recover database using backup controlfile
\*
ERROR at line 1:
ORA-00279: change 855457 generated at 03/16/2015 07:48:55 needed for thread 1
ORA-00289: suggestion :
/u01/oracle/flash_recovery_area/ORCL/archivelog/2015_03_16/o1_mf_1_15_%u_.arc
ORA-00280: change 855457 for thread 1 is in sequence #15
SQL\> alter database recover database using backup controlfile until change 855457;
alter database recover database using backup controlfile until change 855457
\*
ERROR at line 1:
ORA-00275: media recovery has already been started
至此还是没能恢复控制文件，所以我们采取重建控制文件的方法恢复（也可以设置隐藏参数）：
SQL\> CREATE CONTROLFILE REUSE DATABASE orcl NORESETLOGS NOARCHIVELOG
2 MAXLOGFILES 16
3 MAXLOGMEMBERS 3
4 MAXDATAFILES 100
5 MAXINSTANCES 8
6 MAXLOGHISTORY 292
7 logfile
8 GROUP 1 '/u01/oracle/oradata/orcl/redo01.log' SIZE 50M,
9 GROUP 2 '/u01/oracle/oradata/orcl/redo02.log' SIZE 50M,
10 GROUP 3 '/u01/oracle/oradata/orcl/redo03.log' SIZE 50m
11 datafile
12 '/u01/oracle/oradata/orcl/system01.dbf',
13 '/u01/oracle/oradata/orcl/undotbs01.dbf',
14 '/u01/oracle/oradata/orcl/sysaux01.dbf',
15 '/u01/oracle/oradata/orcl/users01.dbf',
16 '/u01/oracle/oradata/orcl/example01.dbf'
17 CHARACTER SET ZHS16GBK
18 /
Control file created.
SQL\> alter database open;
Database altered.
SQL\> select name,value from v$parameter where name like '%control_f%';
NAME VALUE
--------------------------------------------------------------------------------
control_files /u01/oracle/oradata/orcl/control05.ctl
control_file_record_keep_time 7
至此控制文件恢复成功。
****归档、有备份：正确恢复方式****
****SQL\> startup****
****ORACLE instance started.****
****Total System Global Area 285212672 bytes****
****Fixed Size 1218968 bytes****
****Variable Size 100664936 bytes****
****Database Buffers 176160768 bytes****
****Redo Buffers 7168000 bytes****
****ORA-00205: error in identifying control file, check alert log for more info****
****SQL\> ho cp /u01/oracle/ctl.ctl /u01/oracle/oradata/orcl/control01.ctl****
****SQL\> ho cp /u01/oracle/ctl.ctl /u01/oracle/oradata/orcl/control02.ctl****
****SQL\> ho cp /u01/oracle/ctl.ctl /u01/oracle/oradata/orcl/control03.ctl****
****SQL\> shutdown****
****ORA-01507: database not mounted****
****ORACLE instance shut down.****
****SQL\> startup****
****ORACLE instance started.****
****Total System Global Area 285212672 bytes****
****Fixed Size 1218968 bytes****
****Variable Size 100664936 bytes****
****Database Buffers 176160768 bytes****
****Redo Buffers 7168000 bytes****
****Database mounted.****
****ORA-01589: must use RESETLOGS or NORESETLOGS option for database open****
****SQL\> alter database open resetlogs;****
****alter database open resetlogs****
****\*****
****ERROR at line 1:****
****ORA-01194: file 1 needs more recovery to be consistent****
****ORA-01110: data file 1: '/u01/oracle/oradata/orcl/system01.dbf'****
****SQL\> alter database recover database using backup controlfile;****
****alter database recover database using backup controlfile****
****\*****
****ERROR at line 1:****
****ORA-00279: change 864828 generated at 03/16/2015 10:04:20 needed for thread 1****
****ORA-00289: suggestion :****
****/u01/oracle/flash_recovery_area/ORCL/archivelog/2015_03_16/o1_mf_1_16_%u_.arc****
****ORA-00280: change 864828 for thread 1 is in sequence #16****
****SQL\> shutdown****
****ORA-01013: user requested cancel of current operation****
****SQL\> startup force****
****ORACLE instance started.****
****Total System Global Area 285212672 bytes****
****Fixed Size 1218968 bytes****
****Variable Size 100664936 bytes****
****Database Buffers 176160768 bytes****
****Redo Buffers 7168000 bytes****
****Database mounted.****
****ORA-01589: must use RESETLOGS or NORESETLOGS option for database open****
****SQL\> alter database open resetlogs;****
****alter database open resetlogs****
****\*****
****ERROR at line 1:****
****ORA-01113: file 1 needs media recovery****
****ORA-01110: data file 1: '/u01/oracle/oradata/orcl/system01.dbf'****
****SQL\> recover database;****
****ORA-00283: recovery session canceled due to errors****
****ORA-01610: recovery using the BACKUP CONTROLFILE option must be done****
****SQL\> recover database using backup controlfile;****
****ORA-00279: change 864828 generated at 03/16/2015 10:04:20 needed for thread 1****
****ORA-00289: suggestion :****
****/u01/oracle/flash_recovery_area/ORCL/archivelog/2015_03_16/o1_mf_1_16_%u_.arc****
****ORA-00280: change 864828 for thread 1 is in sequence #16****
****Specify log: {\