You want to drop control files from the database, for example, if the location of a control file is no longer appropriate. Remember that the database should have at least two control files at all times.
Shut down the database.
CONTROL_FILES parameter in the database initialization parameter file to delete the old control file name.
Restart the database.
Note:This operation does not physically delete the unwanted control file from the disk. Use operating system commands to delete the unnecessary file after you have dropped the control file from the database.