Oracle database is unavailable

After running below SQL alter query , the Oracle Database is not available

SQL> alter system set db_recovery_file_dest_size=10G;


System altered.

SQL> alter system set db_recovery_file_dest='/u01/app/oracle/fast_recovery_area';

System altered.

I am getting below errors while running SQL query

SQL> startup;
ORA-01261: Parameter db_recovery_file_dest destination string cannot be translated
ORA-01262: Stat failed on a file destination directory
Linux-x86_64 Error: 2: No such file or directory


SQL> show parameter db_recovery_file_dest;
ORA-01034: ORACLE not available
Process ID: 0
Session ID: 0 Serial number: 0


SQL> select name,open_mode from v$database;