rman备份时报错信息：
RMAN-03009: failure of backup command on ORA_DISK_1 channel at 07/03/2012 10:35:17
ORA-19809: limit exceeded for recovery files
ORA-19804: cannot reclaim 52428800 bytes disk space from 2147483648 limit
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03009: failure of backup command on ORA_DISK_1 channel at 07/03/2012 10:35:27
ORA-19809: limit exceeded for recovery files
ORA-19804: cannot reclaim 52428800 bytes disk space from 2147483648 limit
分析原因：
问题是在db_recovery_file_dest_size 备份时没有足够的空间造成的
解决办法：
1：清理过期失效的备份，
2：增加recovery_file_dest_size参数值即可；
SQL> show parameter db_recover
NAME TYPE VALUE
db_recovery_file_dest string /oracle/flash_recovery_area
db_recovery_file_dest_size big integer 2G
SQL> alter system set db_recovery_file_dest_size=4G scope=spfile;
System altered.
重启数据库