Oracle入门教程:RMAN备份归档日志的注意要点(一)

2014-11-24 18:32:08 · 作者: · 浏览: 4

run {
allocate channel c1 type disk maxpiecesize = 2G;
allocate channel c2 type disk maxpiecesize = 2G;
backup incremental level 1 database format '/backup/osedb_osedb01/data/%d_DF_%T_%s_%p.bak'
plus archivelog format '/backup/osedb_osedb01/arch/%d_AF_%T_%s_%p.log' all delete all input;
release channel c1;
release channel c2;
}


注意上面红色字体部分。我一看,感觉好像有些问题,于是在测试机上做了一下试验,发现果然是有错误的。下面进行详细说明。


1. 首先,上面的脚本是错误的,应该将上面红色字体的第一个"all"去掉即可。


2. delete input和delete all input的区别


(1)如果归档日志目录只是一个时,即归档时只有一份归档日志时,上面的两种写法是没有区别的;


(2)如果归档日志目录有多个时,即归档时保存有多份归档日志时,那么:


delete input当备份了归档日志后,会删除第一个归档目录(如:log_archive_dest_1)下的所有归档日志;


delete all input则在备份了归档日志后,所有所有log_archive_dest_n中的备份的archivelog都会被删除。


3. 那么,至于什么时候可以使用all delete input或all delete all input呢?


在1,2小点中提到的写法都是在备份数据库时顺便备份归档日志的写法,如:


backup database plus archivelog delete all input;


而使用all delete all input是直接专门对数据库归档日志进行备份时使用,如:


backup archivelog all delete all input;



附加:


当在备份归档日志时,如果有些归档日志被删除了或是丢失了,那么在备份过程就就会报错RMAN-06059:


假如现数据库有如下的归档日志:


RMAN> list archivelog all;


List of Archived Log Copies


Key Thrd Seq S Low Time Name


------- ---- ------- - --------- -------------


59 1 35 A 16-MAY-11 /u01/backup/arch1/1_35_750725106.dbf


60 1 35 A 16-MAY-11 /u01/backup/arch2/1_35_750725106.dbf


61 1 36 A 16-MAY-11 /u01/backup/arch1/1_36_750725106.dbf


62 1 36 A 16-MAY-11 /u01/backup/arch2/1_36_750725106.dbf


RMAN> backup tablespace app plus archivelog delete all input;


Starting backup at 16-MAY-11


current log archived


using channel ORA_DISK_1


archived log /u01/backup/arch1/1_36_750725106.dbf not found or out of sync with catalog


trying alternate file for archivelog thread 1, sequence 36


RMAN-00571: ===========================================================


RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============


RMAN-00571: ===========================================================


RMAN-03002: failure of backup plus archivelog command at 05/16/2011 03:22:29


RMAN-06059: expected archived log not found, lost of archived log compromises recoverability


ORA-19625: error identifying file /u01/backup/arch2/1_36_750725106.dbf


ORA-27037: unable to obtain file status


Linux Error: 2: No such file or directory


Additional information: 3


这就是因为缺少了36号归档日志的原因,那么现在怎么处理呢?


解决办法:


RMAN> crosscheck archivelog all;


或者:RMAN> change archivelog all crosscheck;


再次执行备份操作即可。


然后需要在RMAN中进行清除操作:


RMAN> list archivelog all;


List of Archived Log Copies
Key Thrd Seq S Low Time Name
------- ---- ------- - --------- ----
62 1 36 X 16-MAY-11 /u01/backup/arch2/1_36_750725106.dbf
61 1 36 X 16-MAY-11 /u01/backup/arch1/1_36_750725106.dbf


RMAN> delete archivelog 61,62;


released channel: ORA_DISK_1
allocated channel: ORA_DISK_1
channel ORA_DISK_1: sid=141 devtype=DISK


List of Archived Log Copies
Key Thrd Seq S Low Time Name
------- ---- ------- - --------- ----
61 1 36 X 16-MAY-11 /u01/backup/arch1/1_36_750725106.dbf
62 1 36 X 16-MAY-11 /u01/backup/arch2/1_36_750725106.dbf


Do you really want to delete the above objects (enter YES or NO) y
deleted archive log
archive log filename=/u01/backup/arch1/1_36_750725106.dbf recid=61 stamp=751258131
deleted archive log
archive log filename=/u01/backup/arch2/1_36_750725106.dbf recid=6