FIX: Backup of availability database via VSS-based application may fail in SQL Server

Taikoma: SQL Server 2016 Enterprise CoreSQL Server 2016 EnterpriseSQL Server 2016 Developer


Assume that you use Availability Groups in Microsoft SQL Server. When you use a Volume Shadow Copy Services (VSS)-based application to back up an availability database, the backup operation may Freeze the system I/O indefinitely. This causes the rendering of any other successive operations to wait until VSS explicitly issues a Thaw. If you try to run a transaction log backup of the same database during this time, you may receive the following error message:

Note Before you receive this error message, you may receive an error message that resembles the following:


This fix is included in the following cumulative updates for SQL Server:

Cumulative Update 1 for SQL Server 2017

Cumulative Update 9 for SQL Server 2016 RTM

Cumulative Update 5 for SQL Server 2016 Service Pack 1

Cumulative Update 8 for SQL Server 2014 SP2


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


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