rman备份归档日志出错 ORA-19625: error identifying file

RMAN> backup archivelog all;

Starting backup at 04-AUG-13
current log archived
using channel ORA_DISK_1
using channel ORA_DISK_2
using channel ORA_DISK_3
using channel ORA_DISK_4
using channel ORA_DISK_5
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03002: failure of backup command at 08/04/2013 10:31:40
RMAN-06059: expected archived log not found, loss of archived log compromises recoverability
ORA-19625: error identifying file /u01/archivelog/1_36_820373180.dbf
ORA-27037: unable to obtain file status
Linux Error: 2: No such file or directory
Additional information: 3

解决办法
RMAN> crosscheck archivelog all;
再备份ok了
RMAN> backup archivelog all;

Starting backup at 04-AUG-13
current log archived
using channel ORA_DISK_1
using channel ORA_DISK_2
using channel ORA_DISK_3
using channel ORA_DISK_4
using channel ORA_DISK_5
channel ORA_DISK_1: starting archived log backup set
channel ORA_DISK_1: specifying archived log(s) in backup set
input archived log thread=1 sequence=21 RECID=123 STAMP=822565772
channel ORA_DISK_1: starting piece 1 at 04-AUG-13
channel ORA_DISK_2: starting archived log backup set
channel ORA_DISK_2: specifying archived log(s) in backup set
input archived log thread=1 sequence=22 RECID=124 STAMP=822565899
channel ORA_DISK_2: starting piece 1 at 04-AUG-13
channel ORA_DISK_3: starting archived log backup set
channel ORA_DISK_3: specifying archived log(s) in backup set
input archived log thread=1 sequence=23 RECID=125 STAMP=822566002
channel ORA_DISK_3: starting piece 1 at 04-AUG-13
channel ORA_DISK_1: finished piece 1 at 04-AUG-13
piece handle=/rmanbk/ORCL_160_20130804.dbf tag=TAG20130804T103322 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:01
channel ORA_DISK_2: finished piece 1 at 04-AUG-13
piece handle=/rmanbk/ORCL_161_20130804.dbf tag=TAG20130804T103322 comment=NONE
channel ORA_DISK_2: backup set complete, elapsed time: 00:00:01
channel ORA_DISK_3: finished piece 1 at 04-AUG-13
piece handle=/rmanbk/ORCL_162_20130804.dbf tag=TAG20130804T103322 comment=NONE
channel ORA_DISK_3: backup set complete, elapsed time: 00:00:02
Finished backup at 04-AUG-13

Starting Control File and SPFILE Autobackup at 04-AUG-13
piece handle=/rmanbk/control_ORCL_c-1348153914-20130804-09 comment=NONE
Finished Control File and SPFILE Autobackup at 04-AUG-13