What Is Oracle Control File

Onur ARDAHANLI

2 years ago

In today’s article, I will be explaining what is Oracle Control File, its place in the operating system, how to back it up and what is kept.

Control File,

The name of our database,

Names and locations of Data Files,

Names and locations of online redo log files,

Sequence number of the online redo log file in use,

Checkpoint information,

If the database is in archive mode and backup is taken, the names and locations of the RMAN backup files,

It is a small binary file that stores the sequence numbers of the archive log files required for successful recovery of the backup.

Its extension is *.ctl. We can see where these files are in the operating system with the following command.

[root@DBONUR ~]# locate *control*.ctl
/oracle/ora11g/backup_ONURDB/control01.ctl
/oracle/ora11g/backup_ONURDB/control02.ctl
/oracle/ora11g/data_ONURDB/ONURDB/control01.ctl
/oracle/ora11g/data_ONURDB/ONURDB/control02.ctl

[root@DBONUR ~]# locate *control*.ctl

/oracle/ora11g/backup_ONURDB/control01.ctl

/oracle/ora11g/backup_ONURDB/control02.ctl

/oracle/ora11g/data_ONURDB/ONURDB/control01.ctl

/oracle/ora11g/data_ONURDB/ONURDB/control02.ctl

Control file content can only be viewed properly when backed up as a trace file. Trace file can also be backed up as follows.

1. SID information of the user logged into the database is learned.

	SQL>  SELECT SID FROM V$SESSION WHERE USERNAME='SYS';
	
	       SID
	----------
	       131

SQL> SELECT SID FROM V$SESSION WHERE USERNAME='SYS';

SID

----------

131

2. We can back up the content of Control File as a trace file with the following command.,

SQL> ALTER DATABASE BACKUP CONTROLFILE TO TRACE;
	
Database altered.

SQL> ALTER DATABASE BACKUP CONTROLFILE TO TRACE;

Database altered.

3. To find which trace file the backup is in, we run the following command.

	SQL> SELECT TRACEFILE FROM V$PROCESS JOIN V$SESSION ON (ADDR=PADDR) WHERE SID=131;
	
	TRACEFILE
	--------------------------------------------------------------------------------
/oracle/diag/rdbms/onurdb/ONURDB/trace/ONURDB_ora_9021.trc

SQL> SELECT TRACEFILE FROM V$PROCESS JOIN V$SESSION ON (ADDR=PADDR) WHERE SID=131;

TRACEFILE

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

/oracle/diag/rdbms/onurdb/ONURDB/trace/ONURDB_ora_9021.trc

4. The contents of the trace file are opened with the vi text editor.

	Trace file /oracle/diag/rdbms/onurdb/ONURDB/trace/ONURDB_ora_20802.trc
	Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
	With the Partitioning, OLAP, Data Mining and Real Application Testing options
	ORACLE_HOME = /oracle/ora11g
	System name:	Linux
	Node name:	DBONUR
	Release:	2.6.18-348.el5
	Version:	#1 SMP Wed Nov 28 21:22:00 EST 2012
	Machine:	x86_64
	VM name:	VMWare Version: 6
	Instance name: ONURDB
	Redo thread mounted by this instance: 1
	Oracle process number: 22
	Unix process pid: 20802, image: oracle@DBONUR
	
	
	*** 2015-06-26 17:12:10.345
	*** SESSION ID:(129.157) 2015-06-26 17:12:10.345
	*** CLIENT ID:() 2015-06-26 17:12:10.345
	*** SERVICE NAME:(SYS$USERS) 2015-06-26 17:12:10.345
	*** MODULE NAME:(TOAD 9.5.0.31) 2015-06-26 17:12:10.345
	*** ACTION NAME:() 2015-06-26 17:12:10.345
	 
	-- The following are current System-scope REDO Log Archival related
	-- parameters and can be included in the database initialization file.
	--
	-- LOG_ARCHIVE_DEST=''
	-- LOG_ARCHIVE_DUPLEX_DEST=''
	--
	-- LOG_ARCHIVE_FORMAT=ONURDB_%t_%s_%r.arc
	--
	-- DB_UNIQUE_NAME="ONURDB"
	--
	-- LOG_ARCHIVE_CONFIG='SEND, RECEIVE, NODG_CONFIG'
	-- LOG_ARCHIVE_MAX_PROCESSES=4
	-- STANDBY_FILE_MANAGEMENT=MANUAL
	-- STANDBY_ARCHIVE_DEST=?/dbs/arch
	-- FAL_CLIENT=''
	-- FAL_SERVER=''
	--
	-- LOG_ARCHIVE_DEST_1='LOCATION=/oracle/ora11g/backup_ONURDB'
	-- LOG_ARCHIVE_DEST_1='OPTIONAL REOPEN=300 NODELAY'
	-- LOG_ARCHIVE_DEST_1='ARCH NOAFFIRM NOEXPEDITE NOVERIFY SYNC'
	-- LOG_ARCHIVE_DEST_1='REGISTER NOALTERNATE NODEPENDENCY'
	-- LOG_ARCHIVE_DEST_1='NOMAX_FAILURE NOQUOTA_SIZE NOQUOTA_USED NODB_UNIQUE_NAME'
	-- LOG_ARCHIVE_DEST_1='VALID_FOR=(PRIMARY_ROLE,ONLINE_LOGFILES)'
	-- LOG_ARCHIVE_DEST_STATE_1=ENABLE
	--
	-- Below are two sets of SQL statements, each of which creates a new
	-- control file and uses it to open the database. The first set opens
	-- the database with the NORESETLOGS option and should be used only if
	-- the current versions of all online logs are available. The second
	-- set opens the database with the RESETLOGS option and should be used
	-- if online logs are unavailable.
	-- The appropriate set of statements can be copied from the trace into
	-- a script file, edited as necessary, and executed when there is a
	-- need to re-create the control file.
	--
	--     Set #1. NORESETLOGS case
	--
	-- The following commands will create a new control file and use it
	-- to open the database.
	-- Data used by Recovery Manager will be lost.
	-- Additional logs may be required for media recovery of offline
	-- Use this only if the current versions of all online logs are
	-- available.
	-- After mounting the created controlfile, the following SQL
	-- statement will place the database in the appropriate
	-- protection mode:
	--  ALTER DATABASE SET STANDBY DATABASE TO MAXIMIZE PERFORMANCE
	STARTUP NOMOUNT
	CREATE CONTROLFILE REUSE DATABASE "ONURDB" NORESETLOGS  NOARCHIVELOG
	    MAXLOGFILES 16
	    MAXLOGMEMBERS 3
	    MAXDATAFILES 100
	    MAXINSTANCES 8
	    MAXLOGHISTORY 292
	LOGFILE
	  GROUP 1 '/oracle/ora11g/data_ONURDB/ONURDB/redo01.log'  SIZE 50M BLOCKSIZE 512,
	  GROUP 2 '/oracle/ora11g/data_ONURDB/ONURDB/redo02.log'  SIZE 50M BLOCKSIZE 512,
	  GROUP 3 '/oracle/ora11g/data_ONURDB/ONURDB/redo03.log'  SIZE 50M BLOCKSIZE 512
	-- STANDBY LOGFILE
	DATAFILE
	  '/oracle/ora11g/data_ONURDB/ONURDB/system01.dbf',
	  '/oracle/ora11g/data_ONURDB/ONURDB/sysaux01.dbf',
	  '/oracle/ora11g/data_ONURDB/ONURDB/undotbs01.dbf',
	  '/oracle/ora11g/data_ONURDB/ONURDB/users01.dbf',
	  '/oracle/ora11g/data_ONURDB/ONURDB/webtvnew01.dbf',
	  '/oracle/ora11g/data_ONURDB/ONURDB/webtvnew02.dbf',
	  '/oracle/ora11g/data_ONURDB/hr_bigts.dbf',
	  '/oracle/ora11g/data_ONURDB/ONURDB/undotbs02.dbf'
	CHARACTER SET WE8ISO8859P9
	;
	-- Commands to re-create incarnation table
	-- Below log names MUST be changed to existing filenames on
	-- disk. Any one log file from each branch can be used to
	-- re-create incarnation records.
	-- ALTER DATABASE REGISTER LOGFILE '/oracle/ora11g/backup_ONURDB/ONURDB_1_1_824297850.arc';
	-- ALTER DATABASE REGISTER LOGFILE '/oracle/ora11g/backup_ONURDB/ONURDB_1_1_880719621.arc';
	-- ALTER DATABASE REGISTER LOGFILE '/oracle/ora11g/backup_ONURDB/ONURDB_1_1_882032561.arc';
	-- Recovery is required if any of the datafiles are restored backups,
	-- or if the last shutdown was not normal or immediate.
	RECOVER DATABASE
	-- Database can now be opened normally.
	ALTER DATABASE OPEN;
	-- Commands to add tempfiles to temporary tablespaces.
	-- Online tempfiles have complete space information.
	-- Other tempfiles may require adjustment.
	ALTER TABLESPACE TEMP ADD TEMPFILE '/oracle/ora11g/data_ONURDB/ONURDB/temp01.dbf'
	     SIZE 20971520  REUSE AUTOEXTEND ON NEXT 655360  MAXSIZE 32767M;
	-- End of tempfile additions.
	--
	--     Set #2. RESETLOGS case
	--
	-- The following commands will create a new control file and use it
	-- to open the database.
	-- Data used by Recovery Manager will be lost.
	-- The contents of online logs will be lost and all backups will
	-- be invalidated. Use this only if online logs are damaged.
	-- After mounting the created controlfile, the following SQL
	-- statement will place the database in the appropriate
	-- protection mode:
	--  ALTER DATABASE SET STANDBY DATABASE TO MAXIMIZE PERFORMANCE
	STARTUP NOMOUNT
	CREATE CONTROLFILE REUSE DATABASE "ONURDB" RESETLOGS  NOARCHIVELOG
	    MAXLOGFILES 16
	    MAXLOGMEMBERS 3
	    MAXDATAFILES 100
	    MAXINSTANCES 8
	    MAXLOGHISTORY 292
	LOGFILE
	  GROUP 1 '/oracle/ora11g/data_ONURDB/ONURDB/redo01.log'  SIZE 50M BLOCKSIZE 512,
	  GROUP 2 '/oracle/ora11g/data_ONURDB/ONURDB/redo02.log'  SIZE 50M BLOCKSIZE 512,
	  GROUP 3 '/oracle/ora11g/data_ONURDB/ONURDB/redo03.log'  SIZE 50M BLOCKSIZE 512
	-- STANDBY LOGFILE
	DATAFILE
	  '/oracle/ora11g/data_ONURDB/ONURDB/system01.dbf',
	  '/oracle/ora11g/data_ONURDB/ONURDB/sysaux01.dbf',
	  '/oracle/ora11g/data_ONURDB/ONURDB/undotbs01.dbf',
	  '/oracle/ora11g/data_ONURDB/ONURDB/users01.dbf',
	  '/oracle/ora11g/data_ONURDB/ONURDB/webtvnew01.dbf',
	  '/oracle/ora11g/data_ONURDB/ONURDB/webtvnew02.dbf',
	  '/oracle/ora11g/data_ONURDB/hr_bigts.dbf',
	  '/oracle/ora11g/data_ONURDB/ONURDB/undotbs02.dbf'
	CHARACTER SET WE8ISO8859P9
	;
	-- Commands to re-create incarnation table
	-- Below log names MUST be changed to existing filenames on
	-- disk. Any one log file from each branch can be used to
	-- re-create incarnation records.
	-- ALTER DATABASE REGISTER LOGFILE '/oracle/ora11g/backup_ONURDB/ONURDB_1_1_824297850.arc';
	-- ALTER DATABASE REGISTER LOGFILE '/oracle/ora11g/backup_ONURDB/ONURDB_1_1_880719621.arc';
	-- ALTER DATABASE REGISTER LOGFILE '/oracle/ora11g/backup_ONURDB/ONURDB_1_1_882032561.arc';
	-- Recovery is required if any of the datafiles are restored backups,
	-- or if the last shutdown was not normal or immediate.
	RECOVER DATABASE USING BACKUP CONTROLFILE
	-- Database can now be opened zeroing the online logs.
	ALTER DATABASE OPEN RESETLOGS;
	-- Commands to add tempfiles to temporary tablespaces.
	-- Online tempfiles have complete space information.
	-- Other tempfiles may require adjustment.
	ALTER TABLESPACE TEMP ADD TEMPFILE '/oracle/ora11g/data_ONURDB/ONURDB/temp01.dbf'
	     SIZE 20971520  REUSE AUTOEXTEND ON NEXT 655360  MAXSIZE 32767M;
	-- End of tempfile additions.
	--

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Trace file /oracle/diag/rdbms/onurdb/ONURDB/trace/ONURDB_ora_20802.trc

Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production

With the Partitioning, OLAP, Data Mining and Real Application Testing options

ORACLE_HOME = /oracle/ora11g

System name: Linux

Node name: DBONUR

Release: 2.6.18-348.el5

Version: #1 SMP Wed Nov 28 21:22:00 EST 2012

Machine: x86_64

VM name: VMWare Version: 6

Instance name: ONURDB

Redo thread mounted by this instance: 1

Oracle process number: 22

Unix process pid: 20802, image: oracle@DBONUR

*** 2015-06-26 17:12:10.345

*** SESSION ID:(129.157) 2015-06-26 17:12:10.345

*** CLIENT ID:() 2015-06-26 17:12:10.345

*** SERVICE NAME:(SYS$USERS) 2015-06-26 17:12:10.345

*** MODULE NAME:(TOAD 9.5.0.31) 2015-06-26 17:12:10.345

*** ACTION NAME:() 2015-06-26 17:12:10.345

-- The following are current System-scope REDO Log Archival related

-- parameters and can be included in the database initialization file.

-- LOG_ARCHIVE_DEST=''

-- LOG_ARCHIVE_DUPLEX_DEST=''

-- LOG_ARCHIVE_FORMAT=ONURDB_%t_%s_%r.arc

-- DB_UNIQUE_NAME="ONURDB"

-- LOG_ARCHIVE_CONFIG='SEND, RECEIVE, NODG_CONFIG'

-- LOG_ARCHIVE_MAX_PROCESSES=4

-- STANDBY_FILE_MANAGEMENT=MANUAL

-- STANDBY_ARCHIVE_DEST=?/dbs/arch

-- FAL_CLIENT=''

-- FAL_SERVER=''

-- LOG_ARCHIVE_DEST_1='LOCATION=/oracle/ora11g/backup_ONURDB'

-- LOG_ARCHIVE_DEST_1='OPTIONAL REOPEN=300 NODELAY'

-- LOG_ARCHIVE_DEST_1='ARCH NOAFFIRM NOEXPEDITE NOVERIFY SYNC'

-- LOG_ARCHIVE_DEST_1='REGISTER NOALTERNATE NODEPENDENCY'

-- LOG_ARCHIVE_DEST_1='NOMAX_FAILURE NOQUOTA_SIZE NOQUOTA_USED NODB_UNIQUE_NAME'

-- LOG_ARCHIVE_DEST_1='VALID_FOR=(PRIMARY_ROLE,ONLINE_LOGFILES)'

-- LOG_ARCHIVE_DEST_STATE_1=ENABLE

-- Below are two sets of SQL statements, each of which creates a new

-- control file and uses it to open the database. The first set opens

-- the database with the NORESETLOGS option and should be used only if

-- the current versions of all online logs are available. The second

-- set opens the database with the RESETLOGS option and should be used

-- if online logs are unavailable.

-- The appropriate set of statements can be copied from the trace into

-- a script file, edited as necessary, and executed when there is a

-- need to re-create the control file.

-- Set #1. NORESETLOGS case

-- The following commands will create a new control file and use it

-- to open the database.

-- Data used by Recovery Manager will be lost.

-- Additional logs may be required for media recovery of offline

-- Use this only if the current versions of all online logs are

-- available.

-- After mounting the created controlfile, the following SQL

-- statement will place the database in the appropriate

-- protection mode:

-- ALTER DATABASE SET STANDBY DATABASE TO MAXIMIZE PERFORMANCE

STARTUP NOMOUNT

CREATE CONTROLFILE REUSE DATABASE "ONURDB" NORESETLOGS NOARCHIVELOG

MAXLOGFILES 16

MAXLOGMEMBERS 3

MAXDATAFILES 100

MAXINSTANCES 8

MAXLOGHISTORY 292

LOGFILE

GROUP 1 '/oracle/ora11g/data_ONURDB/ONURDB/redo01.log' SIZE 50M BLOCKSIZE 512,

GROUP 2 '/oracle/ora11g/data_ONURDB/ONURDB/redo02.log' SIZE 50M BLOCKSIZE 512,

GROUP 3 '/oracle/ora11g/data_ONURDB/ONURDB/redo03.log' SIZE 50M BLOCKSIZE 512

-- STANDBY LOGFILE

DATAFILE

'/oracle/ora11g/data_ONURDB/ONURDB/system01.dbf',

'/oracle/ora11g/data_ONURDB/ONURDB/sysaux01.dbf',

'/oracle/ora11g/data_ONURDB/ONURDB/undotbs01.dbf',

'/oracle/ora11g/data_ONURDB/ONURDB/users01.dbf',

'/oracle/ora11g/data_ONURDB/ONURDB/webtvnew01.dbf',

'/oracle/ora11g/data_ONURDB/ONURDB/webtvnew02.dbf',

'/oracle/ora11g/data_ONURDB/hr_bigts.dbf',

'/oracle/ora11g/data_ONURDB/ONURDB/undotbs02.dbf'

CHARACTER SET WE8ISO8859P9

;

-- Commands to re-create incarnation table

-- Below log names MUST be changed to existing filenames on

-- disk. Any one log file from each branch can be used to

-- re-create incarnation records.

-- ALTER DATABASE REGISTER LOGFILE '/oracle/ora11g/backup_ONURDB/ONURDB_1_1_824297850.arc';

-- ALTER DATABASE REGISTER LOGFILE '/oracle/ora11g/backup_ONURDB/ONURDB_1_1_880719621.arc';

-- ALTER DATABASE REGISTER LOGFILE '/oracle/ora11g/backup_ONURDB/ONURDB_1_1_882032561.arc';

-- Recovery is required if any of the datafiles are restored backups,

-- or if the last shutdown was not normal or immediate.

RECOVER DATABASE

-- Database can now be opened normally.

ALTER DATABASE OPEN;

-- Commands to add tempfiles to temporary tablespaces.

-- Online tempfiles have complete space information.

-- Other tempfiles may require adjustment.

ALTER TABLESPACE TEMP ADD TEMPFILE '/oracle/ora11g/data_ONURDB/ONURDB/temp01.dbf'

SIZE 20971520 REUSE AUTOEXTEND ON NEXT 655360 MAXSIZE 32767M;

-- End of tempfile additions.

-- Set #2. RESETLOGS case

-- The following commands will create a new control file and use it

-- to open the database.

-- Data used by Recovery Manager will be lost.

-- The contents of online logs will be lost and all backups will

-- be invalidated. Use this only if online logs are damaged.

-- After mounting the created controlfile, the following SQL

-- statement will place the database in the appropriate

-- protection mode:

-- ALTER DATABASE SET STANDBY DATABASE TO MAXIMIZE PERFORMANCE

STARTUP NOMOUNT

CREATE CONTROLFILE REUSE DATABASE "ONURDB" RESETLOGS NOARCHIVELOG

MAXLOGFILES 16

MAXLOGMEMBERS 3

MAXDATAFILES 100

MAXINSTANCES 8

MAXLOGHISTORY 292

LOGFILE

GROUP 1 '/oracle/ora11g/data_ONURDB/ONURDB/redo01.log' SIZE 50M BLOCKSIZE 512,

GROUP 2 '/oracle/ora11g/data_ONURDB/ONURDB/redo02.log' SIZE 50M BLOCKSIZE 512,

GROUP 3 '/oracle/ora11g/data_ONURDB/ONURDB/redo03.log' SIZE 50M BLOCKSIZE 512

-- STANDBY LOGFILE

DATAFILE

'/oracle/ora11g/data_ONURDB/ONURDB/system01.dbf',

'/oracle/ora11g/data_ONURDB/ONURDB/sysaux01.dbf',

'/oracle/ora11g/data_ONURDB/ONURDB/undotbs01.dbf',

'/oracle/ora11g/data_ONURDB/ONURDB/users01.dbf',

'/oracle/ora11g/data_ONURDB/ONURDB/webtvnew01.dbf',

'/oracle/ora11g/data_ONURDB/ONURDB/webtvnew02.dbf',

'/oracle/ora11g/data_ONURDB/hr_bigts.dbf',

'/oracle/ora11g/data_ONURDB/ONURDB/undotbs02.dbf'

CHARACTER SET WE8ISO8859P9

;

-- Commands to re-create incarnation table

-- Below log names MUST be changed to existing filenames on

-- disk. Any one log file from each branch can be used to

-- re-create incarnation records.

-- ALTER DATABASE REGISTER LOGFILE '/oracle/ora11g/backup_ONURDB/ONURDB_1_1_824297850.arc';

-- ALTER DATABASE REGISTER LOGFILE '/oracle/ora11g/backup_ONURDB/ONURDB_1_1_880719621.arc';

-- ALTER DATABASE REGISTER LOGFILE '/oracle/ora11g/backup_ONURDB/ONURDB_1_1_882032561.arc';

-- Recovery is required if any of the datafiles are restored backups,

-- or if the last shutdown was not normal or immediate.

RECOVER DATABASE USING BACKUP CONTROLFILE

-- Database can now be opened zeroing the online logs.

ALTER DATABASE OPEN RESETLOGS;

-- Commands to add tempfiles to temporary tablespaces.

-- Online tempfiles have complete space information.

-- Other tempfiles may require adjustment.

ALTER TABLESPACE TEMP ADD TEMPFILE '/oracle/ora11g/data_ONURDB/ONURDB/temp01.dbf'

SIZE 20971520 REUSE AUTOEXTEND ON NEXT 655360 MAXSIZE 32767M;

-- End of tempfile additions.

You can find out what is kept in the Control File by querying the v$controlfile_record_section view. In the v$controlfile view, the names and locations of our control files can be seen.

While opening the database, we can learn where and what the control files are, according to the control_files parameter registered in the spfile or pfile parameter file in the NOMOUNT step.

If it cannot find even one of the control files in the specified names or places, it cannot proceed to the MOUNT step and an error is received.

This can be seen with the test below.

1. The names and locations of Control Files are learned from the Pfile parameter file.

	-bash-3.2$ cd /oracle/ora11g/dbs/
	-bash-3.2$ ll
	total 24
	-rw-rw---- 1 oracle oinstall 1544 Jun 26 16:00 hc_ONURDB.dat
	-rw-r--r-- 1 oracle oinstall  803 May 26 17:09 initONURDB.ora
	-rw-r--r-- 1 oracle oinstall 2851 May 15  2009 init.ora
	-rw-r----- 1 oracle oinstall   24 May 26 12:20 lkONURDB
	-rw-r----- 1 oracle oinstall 1536 May 28 12:37 orapwONURDB
	-rw-r----- 1 oracle oinstall 2560 Jun 28 10:03 spfileONURDB.ora
	
	-bash-3.2$ vi initONURDB.ora
	ONURDB.__db_cache_size=654311424
	ONURDB.__java_pool_size=16777216
	ONURDB.__large_pool_size=33554432
	ONURDB.__oracle_base='/oracle'#ORACLE_BASE set from environment
	ONURDB.__pga_aggregate_target=637534208
	ONURDB.__sga_target=1023410176
	ONURDB.__shared_io_pool_size=0
	ONURDB.__shared_pool_size=301989888
	ONURDB.__streams_pool_size=0
	*.audit_file_dest='/oracle/admin/ONURDB/adump'
	*.audit_trail='db'
	*.compatible='11.2.0.4.0'
	*.control_files='/oracle/ora11g/data_ONURDB/ONURDB/control01.ctl','/oracle/ora11g/data_ONURDB/ONURDB/control02.ctl'
	*.db_block_size=8192
	*.db_domain=''
	*.db_name='ONURDB'
	*.diagnostic_dest='/oracle'
	*.dispatchers='(PROTOCOL=TCP) (SERVICE=ONURDBXDB)'
	*.log_archive_dest_1='location=/oracle/ora11g/backup_ONURDB'
	*.log_archive_format='ONURDB_%t_%s_%r.arc'
	*.memory_target=1655701504
	*.open_cursors=300
	*.processes=150
	*.remote_login_passwordfile='EXCLUSIVE'
*.undo_tablespace='UNDOTBS1'

-bash-3.2$ cd /oracle/ora11g/dbs/

-bash-3.2$ ll

total 24

-rw-rw---- 1 oracle oinstall 1544 Jun 26 16:00 hc_ONURDB.dat

-rw-r--r-- 1 oracle oinstall 803 May 26 17:09 initONURDB.ora

-rw-r--r-- 1 oracle oinstall 2851 May 15 2009 init.ora

-rw-r----- 1 oracle oinstall 24 May 26 12:20 lkONURDB

-rw-r----- 1 oracle oinstall 1536 May 28 12:37 orapwONURDB

-rw-r----- 1 oracle oinstall 2560 Jun 28 10:03 spfileONURDB.ora

-bash-3.2$ vi initONURDB.ora

ONURDB.__db_cache_size=654311424

ONURDB.__java_pool_size=16777216

ONURDB.__large_pool_size=33554432

ONURDB.__oracle_base='/oracle'#ORACLE_BASE set from environment

ONURDB.__pga_aggregate_target=637534208

ONURDB.__sga_target=1023410176

ONURDB.__shared_io_pool_size=0

ONURDB.__shared_pool_size=301989888

ONURDB.__streams_pool_size=0

*.audit_file_dest='/oracle/admin/ONURDB/adump'

*.audit_trail='db'

*.compatible='11.2.0.4.0'

*.control_files='/oracle/ora11g/data_ONURDB/ONURDB/control01.ctl','/oracle/ora11g/data_ONURDB/ONURDB/control02.ctl'

*.db_block_size=8192

*.db_domain=''

*.db_name='ONURDB'

*.diagnostic_dest='/oracle'

*.dispatchers='(PROTOCOL=TCP) (SERVICE=ONURDBXDB)'

*.log_archive_dest_1='location=/oracle/ora11g/backup_ONURDB'

*.log_archive_format='ONURDB_%t_%s_%r.arc'

*.memory_target=1655701504

*.open_cursors=300

*.processes=150

*.remote_login_passwordfile='EXCLUSIVE'

*.undo_tablespace='UNDOTBS1'

Or run the command below while on the SQL prompt.

	SQL> show parameter control_files
	
	NAME                                 TYPE        VALUE
	------------------------------------ ----------- ------------------------------
	control_files                        string      /oracle/ora11g/data_ONURDB/ONU
	                                                 RDB/control01.ctl, /oracle/ora
	                                                 11g/data_ONURDB/ONURDB/control
	                                                 02.ctl

SQL> show parameter control_files

NAME TYPE VALUE

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

control_files string /oracle/ora11g/data_ONURDB/ONU

RDB/control01.ctl, /oracle/ora

11g/data_ONURDB/ONURDB/control

02.ctl

2. Change the name of one of the Control Files.

	-bash-3.2$ mv control02.ctl control02.ctl.old

1	-bash-3.2$ mv control02.ctl control02.ctl.old

3. The database is closed.

	SQL> shutdown immediate;
	Database closed.
	Database dismounted.
ORACLE instance shut down.

SQL> shutdown immediate;

Database closed.

Database dismounted.

ORACLE instance shut down.

4. The database opens.

	SQL> startup
	ORACLE instance started.
	
	Total System Global Area 1653518336 bytes
	Fixed Size                  2253784 bytes
	Variable Size             989858856 bytes
	Database Buffers          654311424 bytes
	Redo Buffers                7094272 bytes
	ORA-00205: error in identifying control file, check alert log for more info

SQL> startup

ORACLE instance started.

Total System Global Area 1653518336 bytes

Fixed Size 2253784 bytes

Variable Size 989858856 bytes

Database Buffers 654311424 bytes

Redo Buffers 7094272 bytes

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