How to Recover lost control file in oracle?

  Control file is the most important file in Oracle , if lose one , we are not able to start oracle instance. 
   At least we need to have one control file in order to  successfully start oracle instance. In case you lost your control file,

    In the absence of at least one of the control file(which is registered in parameter file) ,   you will face ORA-00205 (error identifying a control file) 

     

 To resolve the above error and recover the lost control file we have three different options : 
    

                       Option 1 :-

    If you have a backup/copy the lost control file at hand  and also you   know the previous location and name of the control file, just copy to all locations with the same name as previous one,the copy can be done with OS command or simple copy and  paste following the below steps.

Steps to restore lost control file, to its previous location and previous name:-

1.Shutdown the database

2.Copy the control file to its previous location

3.Shutdown again

4.Startup / startup open

                        

Now you should be able start the instance successfully.

           

But ,  If you don't know the previous name and location , follow the below steps to restore the control file to new location and new name.

 Steps to restore lost control file, to new location and new name:-

1.Shutdown the database

2.Copy or move the control file to the new location

3.Startup nomount and edit the path for the control file in pfile or set the path for control file using alter system (for spfile)

    pfile:-  CONTROL_FILES = (‘u01//app/oradata/ord/control01.ctl’,‘u01//app/oradata/ord/control02.ctl’)

    spfile:-  Alter system set CONTROL_FILES=’u01//app/oradata/ord/control01.ctl’, ’ u01//app/oradata/ord/control02.ctl’ scope=spfile;

4. Shutdown the instance

5. Startup open;