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

if you have backup of controlfile just restore it or copy it.let me create a scenario and move the controlfile
so that what error i will get and how can we restore it .



[oracle@ebsofdp ebsofdp]$ mv control01.ctl control01.ctl_12jan2013
[oracle@ebsofdp ebsofdp]$ ls -tlrh
total 1.6G
-rw-r----- 1 oracle dba  29M Jan 10 17:25 temp01.dbf
-rw-r----- 1 oracle dba  51M Jan 12 17:20 redo02.log
-rw-r----- 1 oracle dba  51M Jan 12 17:20 redo01.log
-rw-r----- 1 oracle dba 5.1M Jan 12 17:21 users01.dbf
-rw-r----- 1 oracle dba  76M Jan 12 17:21 undotbs01.dbf
-rw-r----- 1 oracle dba  11M Jan 12 17:21 tz01.dbf
-rw-r----- 1 oracle dba 701M Jan 12 17:21 system01.dbf
-rw-r----- 1 oracle dba 601M Jan 12 17:21 sysaux01.dbf
-rw-r----- 1 oracle dba  51M Jan 12 17:21 redo03.log
-rw-r----- 1 oracle dba 9.3M Jan 12 17:21 control03.ctl
-rw-r----- 1 oracle dba 9.3M Jan 12 17:21 control02.ctl
-rw-r----- 1 oracle dba 9.3M Jan 12 17:21 control01.ctl_12jan2013
[oracle@ebsofdp ebsofdp]$ sqlplus "/as sysdba"

SQL*Plus: Release 11.1.0.6.0 - Production on Sat Jan 12 17:23:56 2013

Copyright (c) 1982, 2007, Oracle.  All rights reserved.

Connected to an idle instance.

SQL> startup
ORACLE instance started.

Total System Global Area  839282688 bytes
Fixed Size                  2149040 bytes
Variable Size             440403280 bytes
Database Buffers          390070272 bytes
Redo Buffers                6660096 bytes
ORA-00205: error in identifying control file, check alert log for more info
SQL>

The more information can also be get from v$controlfile and alert_<sid>.log file.

Go to cd $ORACLE_HOME/dbs locatioion  and open pfile 

and put the entry control01.ctl_12jan2013 instead of control01.ctl OR if you have multiple controlfile copy it other locaton and now startup your database.Make sure there is no spfile in dbs location.

SQL> startup

ORACLE instance started.

Total System Global Area  839282688 bytes

Fixed Size                  2149040 bytes

Variable Size             440403280 bytes

Database Buffers          390070272 bytes

Redo Buffers                6660096 bytes

Database mounted.

Database opened.

SQL>