閃回恢復區大小不夠。報ORA-19809、ORA-19804

問題： 閃回恢復區大小不夠，rman默認備份路徑報錯。
RMAN> backup database;


Starting backup at 01-DEC-14
using target database control file instead of recovery catalog
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=39 device type=DISK
channel ORA_DISK_1: starting full datafile backup set
channel ORA_DISK_1: specifying datafile(s) in backup set
input datafile file number=00006 name=/home/oracle/app/oradata/orcl/ogg01.dbf
input datafile file number=00001 name=/home/oracle/app/oradata/orcl/system01.dbf
input datafile file number=00002 name=/home/oracle/app/oradata/orcl/sysaux01.dbf
input datafile file number=00005 name=/home/oracle/app/oradata/orcl/tbtb01.dbf
input datafile file number=00003 name=/home/oracle/app/oradata/orcl/undotbs01.dbf
input datafile file number=00004 name=/home/oracle/app/oradata/orcl/users01.dbf
channel ORA_DISK_1: starting piece 1 at 01-DEC-14
RMAN-03009: failure of backup command on ORA_DISK_1 channel at 12/01/2014 06:43:49
ORA-19809: limit exceeded for recovery files
ORA-19804: cannot reclaim 52428800 bytes disk space from 2147483648 limit
continuing other job steps, job failed will not be re-run
channel ORA_DISK_1: starting full datafile backup set
channel ORA_DISK_1: specifying datafile(s) in backup set
including current control file in backup set
including current SPFILE in backup set
channel ORA_DISK_1: starting piece 1 at 01-DEC-14
channel ORA_DISK_1: finished piece 1 at 01-DEC-14
piece handle=/home/oracle/app/flash_recovery_area/ORCL/backupset/2014_12_01/o1_mf_ncsnf_TAG20141201T064122_b7ro3pt5_.bkp tag=TAG20141201T064122 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:02
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================


RMAN-03009: failure of backup command on ORA_DISK_1 channel at 12/01/2014 06:43:49
ORA-19809: limit exceeded for recovery files
ORA-19804: cannot reclaim 52428800 bytes disk space from 2147483648 limit


原因：閃回恢復區大小不夠
oracle10g,11g在默認情況下，歸檔日志是保存在閃回恢復區的，如果你建庫的時候用的默認設置，
閃回恢復區應該是2G，空間不夠，沒辦備份。（同理歸檔日志保存也可能碰到這個問題，導致無法再歸檔）
解決：
（1）調整添加閃回區大小
（2）將備份的目錄換成其他路徑。
     如果是歸檔報錯，即將歸檔目錄設置到其他目錄，修改alter system set log_archive_dest = 其他路徑 
步驟：


1、查看db_recovery_file_dest 大小
SQL> show parameter recover


NAME     TYPE VALUE
------------------------------------ ----------- ------------------------------
db_recovery_file_dest     string/home/oracle/app/flash_recover
y_area
db_recovery_file_dest_size     big integer 2G
recovery_parallelism     integer0


2、 查看閃回恢復區使用情況
SQL> select file_type, percent_space_used as used,percent_space_reclaimable as reclaimable, number_of_files as "number" from v$flash_recovery_area_usage;


FILE_TYPE                  USED RECLAIMABLE     number
-------------------- ---------- ----------- ----------
CONTROL FILE                  0           0          0
REDO LOG                      0           0          0
ARCHIVED LOG              46.76           0         23
BACKUP PIECE                .46           0          1
IMAGE COPY                    0           0          0
FLASHBACK LOG                 0           0          0
3、 擴展db_recovery_file_dest 大小
SQL> alter system set db_recovery_file_dest_size=10G scope=both;      


System altered.


4、利用run批腳本指定備份路徑來備份   （建議歸檔與備份分開放置）
run{
allocate channel ch1 type disk;
allocate channel ch2 type disk;
backup incremental level 0 database plus archivelog  delete input
format '/home/oracle/rmanbak/db_%d_%U'
tag=db_inc_0;
release channel ch1;
release channel ch2;
}


allocated channel: ch1
。。。。。。
released channel: ch1
released channel: ch2