To switch on flashback on the database if FRA space is not sufficient to accomodate the flashback log files then,
SQL> alter database flashback on; alter database flashback on * ERROR at line 1: ORA-38706: Cannot turn on FLASHBACK DATABASE logging. ORA-38708: not enough space for first flashback database log file SQL> !oerr ora 38708 38708, 00000, "not enough space for first flashback database log file" // *Cause: An ALTER DATABASE FLASHBACK ON command failed because there // was not enough space in the Recovery Area for the first // flashback database log file. // *Action: Make more space in the Recovery Area. For example, this // can be done by increasing the value of // DB_RECOVERY_FILE_DEST_SIZE.
Increase FRA!
SQL> alter system set db_recovery_file_dest_size=10000M; System altered. SQL> alter database flashback on; Database altered.