操作環境：redhat 6.4  oracle 12c

rman備份出錯。之前出現過，好象重新backup database就可以了，今天又出現，紀錄下

ORA-19804: cannot reclaim 67108864 bytes disk space from 10737418240 bytes limit

SQL> show parameter db_recovery_file_dest;
NAME      TYPE VALUE
------------------------------------ ----------- ------------------------------
db_recovery_file_dest      string /opt/oracle/t1/flashback
db_recovery_file_dest_size      big integer 10G
alter system set db_recovery_file_dest_size=20g scope=both;