clare.xia (2/9/2011)
Msg 824, Level 24, State 2, Line 1SQL Server detected a logical consistency-based I/O error: incorrect checksum (expected: 0x6f9014c7; actual: 0x6f903ecb). It occurred during a read of page (2:0) in database ID 4 at offset 0000000000000000 in file 'C:\Program Files\Microsoft SQL Server\MSSQL.1\MSSQL\DATA\MSDBLog.ldf'. Additional messages in the SQL Server error log or system event log may provide more detail. This is a severe error condition that threatens database integrity and must be corrected immediately. Complete a full database consistency check (DBCC CHECKDB). This error can be caused by many factors; for more information, see SQL Server Books Online.
File 2 is the log file, confirmed by the name. Page 0 is at the beginning of the file, confirmed by the offset. At the beginning of the log is the log header. Hence you have a checksum error (yes, logs do have checksums) in the log header. Not repairable.
Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability