You have following choices to free up space from flash recovery area:

1. Consider changing RMAN RETENTION POLICY. If you are using Data Guard,

then consider changing RMAN ARCHIVELOG DELETION POLICY.

2. Back up files to tertiary device such as tape using RMAN

BACKUP RECOVERY AREA command.

3. Add disk space and increase db_recovery_file_dest_size parameter to

reflect the new space.

4. Delete unnecessary files using RMAN DELETE command. If an operating

system command was used to delete files, then use RMAN CROSSCHECK and

DELETE EXPIRED commands.

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flash recovery area 空间满了的处理办法