KB4513099 - FIX: Azure storage I/O subsystem may not reset transfer details for a failed I/O resulting in backup errors

Applies to: SQL Server 2016 Service Pack 2SQL Server 2016 DeveloperSQL Server 2016 Enterprise


Azure storage I/O subsystem, on some rare occasions, may notreset the number of bytes transferred for a failed I/O. This results in backupengine making an incorrect assumption of the number of bytes that weresuccessfully written to the storage which causes subsequent backup errors. It is more likely to encounter these errors if the I/Os to Azure Storage are throttled consistently.


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


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

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