You can use Oracle Enterprise Manager Database Express (EM Express) to view location and status information about control files.
In a multitenant container database (CDB), EM Express provides control file information only in the root, not in the pluggable databases (PDBs).
To view control file information:
The Control Files page appears.
This page shows whether your database has a multiplexed control file. The List of Control Files and Control Files sections give you more detailed information about your control files.
See Oracle Database Backup and Recovery User's Guide for more information about backing up the control file to a trace file.