If you have enabled the autobackup of the control file feature, the spfile will be backed up automatically (along with the control file) anytime a BACKUP or COPY command is issued. If you need to back up the spfile manually, use the following command:
RMAN> backup spfile;
The location of the file that contains the backup of the spfile is dependent on what you have configured for the autobackup of the control file (see the previous section for an example). By default, if you don’t use an FRA, and you haven’t explicitly configured a location via a channel, then for Linux/Unix servers, the backup goes to the ORACLE_HOME/dbs directory.
Note RMAN can only back up the spfile if the instance was started using a spfile.