We have an instance of SQL Server 2008 R2 SP2 sitting in a DMZ. When I back up one of its databases to a drive local to that server, then run a RESTORE VERIFYONLY against the backup file, it declares the backup set valid.
If I subsequently robocopy the backup file to a mapped drive, pointing to a server located in our domain, then run a RESTORE VERIFYONLY (or a full RESTORE DATABASE, for that matter) against the copied backup file, while connected to a SQL Server instance which is also in the domain (running SQL Server 2008 R2 SP3), the subsequent RESTORE returns the following error message:
Msg 3203, Level 16, State 1, Line 1 Read on "<Backup file path>" failed: 13(The data is invalid.) Msg 3013, Level 16, State 1, Line 1 VERIFY DATABASE is terminating abnormally.
This happens consistently and is repeatable. Anyone have any ideas as to what might be corrupting the copied backup file? Does robocopy feature any validation flags that might be useful? What's the best way to troubleshoot this?