FIX: Errors 3212 and 3013 occur when you backup a database using MIRROR TO DISK option in SQL Server 2017

Applies to: SQL Server 2017 Developer on WindowsSQL Server 2017 Enterprise on WindowsSQL Server 2017 Enterprise Core on Windows


Assume that you use the MIRROR TO DISK option when backing up a database in SQL Server 2017 in order to write the backup to multiple targets.  If the disk specified in the MIRROR TO DISK option is formatted with a different sector size than the primary backup target disk, you will receive the following error:

Msg 3212, Level 16, State 0, Line LineNumber

The mirror device "FilePath\FileName" and the mirror device "FilePath\FileName" have different device specifications.

Msg 3013, Level 16, State 1, Line LineNumber

BACKUP DATABASE is terminating abnormally.


This issue is fixed in the following cumulative update for SQL Server:

       Cumulative Update 10 for SQL Server 2017

Note: In addition to the cumulative update, you must specify the BLOCKSIZE parameter in the backup command to resolve the difference in formatting.  The BLOCKSIZE parameter should be set to the higher of the two sector sizes. 

For example, if the primary target has a 512B sector size and the mirror disk has a 4K sector size then the BLOCKSIZE parameter should be set to 4096.


To work around this issue, you can enable Trace Flag(TF) 1800.


Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.


Learn about the terminology that Microsoft uses to describe software updates.