一台数据库服务器的事务日志备份作业偶尔会出现几次备份失败的情况，具体的错误信息为：
DATE/TIME: 2018/7/30 12:10:52
DESCRIPTION: BackupDiskFile::CreateMedia: Backup device 'M:\DB_BACKUP\LOG_BACKUP\xxxx_[2018-07-30_06h03m10_Mon]_logs.TRN' failed to create. Operating system error 32(failed to retrieve text for this error. Reason: 15105).
COMMENT: (None)
JOB RUN: (None)
关于Operating system error 32，这个错误代码对应的错误信息为：
The process cannot access the file because it is being used by another process.
其实以前刚好遇到过这样的案例，使用AplexSQL Log去分析事务日志的备份文件，YourSQLDba的事务日志备份的时候，就会遇到上面错误（YourSQLDba_LogBackups事务日志备份会追加到同一个备份文件），但是这个怎么定位这个错误呢？其实出现这个错误，一定有相关进程在访问事务日志备份文件，那么只要排查这些应用或程序即可。刚好最近配置了AWS的DMS的（DMS简单介绍如下，具体参考官方文档https://docs.aws.amazon.com/zh_cn/dms/latest/userguide/Welcome.html）
在最基本级别上，AWS DMS 是 AWS 云中运行复制软件的服务器。您创建源和目标连接以告知 AWS DMS 要进行提取和加载的位置。然后，计划在此服务器上运行以迁移数据的任务。AWS DMS 会创建表和关联的主键 (如果它们在目标上不存在)。如果您愿意，则可以预先手动创建目标表。或者，也可以使用 AWS SCT 创建部分或全部目标表、索引、视图、触发器等。
因为DMS有时候会读取事务日志备份文件中的内容，通过DPA监控，刚好找的了这个DMS的账号，在事务日志备份的时间点在执行下面SQL语句（如下所示）。那么就是因为这个进程在读取事务日志备份中内容（跟普通的Replication有点不同），导致事务日志备份出现Operating system error 32错误（The process cannot access the file because it is being used by another process）
SELECT /* top 50000 */
[Current LSN] ,
[Operation] ,
[Context] ,
[Transaction ID] ,
[Transaction Name] ,
[Begin Time] ,
[End Time] ,
[Flag Bits] ,
[PartitionId] ,
[Page ID] ,
[Slot ID] ,
[RowLog Contents 0] ,
[Log Record] ,
[RowLog Contents 1]
FROM sys.fn_dump_dblog(@P1, NULL, NULL, 11,
'M:\DB_BACKUP\LOG_BACKUP\xxxx_[2018-08-01_06h06m19_Wed]_logs.TRN',
NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL)
WHERE [Current LSN] COLLATE SQL_Latin1_General_CP1_CI_AS >= @P2 COLLATE SQL_Latin1_General_CP1_CI_AS
AND ( ( [Operation] IN ( 'LOP_COMMIT_XACT', 'LOP_ABORT_XACT' )
OR ( [Operation] = 'LOP_BEGIN_XACT' /* and [Transaction SID]=SUSER_SID('') */ ))
OR ( ( ( [Operation] IN ( 'LOP_INSERT_ROWS', 'LOP_DELETE_ROWS' )
AND [Context] IN ( 'LCX_HEAP', 'LCX_CLUSTERED',
'LCX_MARK_AS_GHOST' )
)
OR ( [Operation] IN ( 'LOP_INSERT_ROWS', 'LOP_MODIFY_ROW' )
AND [Context] = 'LCX_TEXT_MIX'
AND DATALENGTH([RowLog Contents 0]) IN ( 0, 14, 28 )
)
)
AND [PartitionId] IN ( 72057596166537216, 72057596166471680,
72057596166406144, 72057596327559168,
72057596160180224, 72057596361506816,
72057596119613440, 72057596119744512,
72057596119678976, 72057596120006656,
72057596119941120, 72057596120137728,
72057596545859584, 72057596119810048,
72057596231417856, 72057596418523136,
72057596441067520, 72057596381364224,
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72057596248326144, 72057596248391680,
72057594565754880, 2465937948672,
72057596374810624, 72057594565885952,
72057596133113856, 72057596563357696,
48281791823872, 116258596192256,
72057596132851712, 72057595963179008,
72057596541861888, 72057594599047168,
53296886710272, 72057595944894464,
72057594566934528, 72057594567000064,
72057596526395392, 72057596526592000,
72057595964030976, 72057595965079552,
72057594582859776, 72057594567917568,
72057596525936640, 72057595908128768,
72057594568048640, 119223456956416,
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72057596133179392, 72057596132786176,
72057595965931520, 72057595966455808,
72057596450177024, 72057595966849024,
112563398705152, 72057596184363008,
72057596184428544, 72057594681425920,
72057596309733376, 72057596205334528,
72057596184231936, 72057595458355200,
107370836852736, 72057595852423168,
72057595708702720, 72057596357312512,
72057596357378048, 72057596550119424,
72057596301279232, 72057596357050368,
72057596356984832, 72057596362293248,
72057596357574656, 72057596357246976,
72057596357181440, 72057596301344768,
72057595809890304, 72057595873591296,
72057595969011712, 72057595969536000,
72057596348858368, 72057595970191360,
72057596217917440, 72057596217982976,
72057596526329856, 72057596332212224,
114660558176256, 72057596526460928,
72057596331687936, 72057596331622400,
72057595970781184, 72057596574826496,
72057596317859840, 72057594572242944,
72057594592952320, 72057595971502080,
72057595991228416, 72057596324282368,
72057596220538880, 72057595972943872,
72057596512370688, 72057594640334848,
72057595973730304, 72057596132655104,
72057594573684736, 72057594574012416,
72057594776649728, 72057595974320128,
72057594574798848, 45591660199936,
72057594590920704, 72057595974778880,
72057594593738752, 72057595975106560,
72057595975696384, 72057595937882112,
140014173224960, 72057594576240640,
72057594576502784, 72057596501819392,
72057596188360704, 72057596526264320,
61775963815936, 56442625916928,
72057596350365696, 14271632703488,
72057596268838912, 72057596575744000,
72057596442836992, 72057596459089920,
72057596440281088, 72057596469444608,
72057596413935616, 72057596414001152,
72057596532293632, 72057596413739008,
72057596414066688, 72057596548743168,
72057596548612096, 72057596195110912,
72057596448014336, 72057594576961536,
72057594581614592, 72057594577354752,
72057596310061056, 72057596488384512,
72057594577813504, 72057596309995520,
72057596181151744, 72057594577551360 )
)
OR ( [Operation] = 'LOP_HOBT_DDL' )
);