rman备份archivelog时出现以下错误： rmangt; backup archivelog all delete input; starting backup at 14-apr-14 current log
rman备份archivelog时出现以下错误：
rman> backup archivelog all delete input;
starting backup at 14-apr-14
current log archived
using channel ora_disk_1
using channel ora_disk_2
rman-00571: ===========================================================
rman-00569: =============== error message stack follows ===============
rman-00571: ===========================================================
rman-03002: failure of backup command at 04/14/2014 18:40:23
rman-06059: expected archived log not found, loss of archived log compromises recoverability
ora-19625: error identifying file /home/oracle/prod/1_2_844469007.dbf
ora-27037: unable to obtain file status
linux error: 2: no such file or directory
additional information: 3
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网上查了出错原因是由于操作系统下删除了这个归档日志，这个日志还没备份过，rman去备份的时候，找不到这个归档就出错了。可使用change archivelog all crosscheck命令来解决此问题，如下：
rman> change archivelog all crosscheck;
released channel: ora_disk_1
released channel: ora_disk_2
allocated channel: ora_disk_1
channel ora_disk_1: sid=43 device type=disk
allocated channel: ora_disk_2
channel ora_disk_2: sid=45 device type=disk
validation succeeded for archived log
archived log file name=/home/oracle/prod/1_16_827176743.dbf recid=1 stamp=844399662
validation succeeded for archived log
archived log file name=/home/oracle/prod/1_17_827176743.dbf recid=2 stamp=844460245
validation succeeded for archived log
archived log file name=/home/oracle/prod/1_18_827176743.dbf recid=3 stamp=844461320
validation succeeded for archived log
archived log file name=/home/oracle/prod/1_19_827176743.dbf recid=4 stamp=844461426
validation succeeded for archived log
archived log file name=/home/oracle/prod/1_20_827176743.dbf recid=5 stamp=844461580
validation succeeded for archived log
archived log file name=/home/oracle/prod/1_21_827176743.dbf recid=6 stamp=844461592
validation succeeded for archived log
archived log file name=/home/oracle/prod/1_22_827176743.dbf recid=7 stamp=844461696
validation succeeded for archived log
archived log file name=/home/oracle/prod/1_23_827176743.dbf recid=8 stamp=844462037
validation succeeded for archived log
archived log file name=/home/oracle/prod/1_24_827176743.dbf recid=9 stamp=844462165
validation succeeded for archived log
archived log file name=/home/oracle/prod/1_25_827176743.dbf recid=10 stamp=844462279
validation succeeded for archived log
archived log file name=/home/oracle/prod/1_26_827176743.dbf recid=11 stamp=844462409
validation succeeded for archived log
archived log file name=/home/oracle/prod/1_27_827176743.dbf recid=12 stamp=844465108
validation succeeded for archived log
archived log file name=/home/oracle/prod/1_28_827176743.dbf recid=13 stamp=844469010
validation succeeded for archived log
archived log file name=/home/oracle/prod/1_1_844532679.dbf recid=16 stamp=844533450
validation succeeded for archived log
archived log file name=/home/oracle/prod/1_2_844532679.dbf recid=19 stamp=844537684
validation succeeded for archived log
archived log file name=/home/oracle/prod/1_2_844532679.dbf recid=17 stamp=844533553
validation succeeded for archived log
archived log file name=/home/oracle/prod/1_3_844532679.dbf recid=20 stamp=844537685
validation succeeded for archived log
archived log file name=/home/oracle/prod/1_4_844532679.dbf recid=18 stamp=844537684
validation succeeded for archived log
archived log file name=/home/oracle/prod/1_1_844537684.dbf recid=23 stamp=844605032
validation succeeded for archived log
archived log file name=/home/oracle/prod/1_1_844537684.dbf recid=21 stamp=844575254
validation succeeded for archived log
archived log file name=/home/oracle/prod/1_2_844537684.dbf recid=24 stamp=844605033
validation succeeded for archived log
archived log file name=/home/oracle/prod/1_2_844537684.dbf recid=22 stamp=844581004
validation succeeded for archived log
archived log file name=/home/oracle/prod/1_3_844537684.dbf recid=25 stamp=844605034
validation succeeded for archived log
archived log file name=/home/oracle/prod/1_1_844469007.dbf recid=14 stamp=844530587
validation succeeded for archived log
archived log file name=/home/oracle/prod/1_1_844605031.dbf recid=26 stamp=844670045
validation succeeded for archived log
archived log file name=/home/oracle/prod/1_2_844605031.dbf recid=27 stamp=844797748
validation succeeded for archived log
archived log file name=/home/oracle/prod/1_3_844605031.dbf recid=28 stamp=844841532
validation succeeded for archived log
archived log file name=/home/oracle/prod/1_4_844605031.dbf recid=29 stamp=844847317
validation succeeded for archived log
archived log file name=/home/oracle/prod/1_5_844605031.dbf recid=30 stamp=844855807
validation succeeded for archived log
archived log file name=/home/oracle/prod/1_6_844605031.dbf recid=31 stamp=844855838
validation succeeded for archived log
archived log file name=/home/oracle/prod/1_7_844605031.dbf recid=32 stamp=844886422
validation succeeded for archived log
archived log file name=/home/oracle/prod/1_8_844605031.dbf recid=33 stamp=844886590
validation succeeded for archived log
archived log file name=/home/oracle/prod/1_9_844605031.dbf recid=34 stamp=844886622
crosschecked 33 objects
validation failed for archived log
archived log file name=/home/oracle/prod/1_2_844469007.dbf recid=15 stamp=844530793
crosschecked 1 objects
--再次执行archivelog的rman备份就成功了，如下：
rman> backup archivelog all delete input;
starting backup at 14-apr-14
current log archived
using channel ora_disk_1
using channel ora_disk_2
channel ora_disk_1: starting compressed archived log backup set
channel ora_disk_1: specifying archived log(s) in backup set
input archived log thread=1 sequence=16 recid=1 stamp=844399662
input archived log thread=1 sequence=17 recid=2 stamp=844460245
input archived log thread=1 sequence=18 recid=3 stamp=844461320
channel ora_disk_1: starting piece 1 at 14-apr-14
channel ora_disk_2: starting compressed archived log backup set
channel ora_disk_2: specifying archived log(s) in backup set
input archived log thread=1 sequence=1 recid=16 stamp=844533450
channel ora_disk_2: starting piece 1 at 14-apr-14
channel ora_disk_2: finished piece 1 at 14-apr-14
piece handle=/home/oracle/backup/prod_20140414_1bp5ntq0_1_1.bak tag=tag20140414t190432 comment=none
channel ora_disk_2: backup set complete, elapsed time: 00:00:02
channel ora_disk_2: deleting archived log(s)
archived log file name=/home/oracle/prod/1_1_844532679.dbf recid=16 stamp=844533450
channel ora_disk_2: starting compressed archived log backup set
channel ora_disk_2: specifying archived log(s) in backup set
input archived log thread=1 sequence=19 recid=4 stamp=844461426
input archived log thread=1 sequence=20 recid=5 stamp=844461580
input archived log thread=1 sequence=21 recid=6 stamp=844461592
input archived log thread=1 sequence=22 recid=7 stamp=844461696
input archived log thread=1 sequence=23 recid=8 stamp=844462037
input archived log thread=1 sequence=24 recid=9 stamp=844462165
input archived log thread=1 sequence=25 recid=10 stamp=844462279
channel ora_disk_2: starting piece 1 at 14-apr-14
channel ora_disk_1: finished piece 1 at 14-apr-14
piece handle=/home/oracle/backup/prod_20140414_1ap5ntq0_1_1.bak tag=tag20140414t190432 comment=none
channel ora_disk_1: backup set complete, elapsed time: 00:00:03
channel ora_disk_1: deleting archived log(s)