Consider the following scenario:
You deploy a Windows Server 2012-based failover cluster. The cluster contains two nodes (node A and node B).
A SCSI disk is used for the failover cluster. The disk is a shared disk and is accessible by both node A and node B.
Node A restarts or crashes. Then, the cluster fails over to node B.
Node A comes back online.
Node B is shut down and the cluster fails over to node A.
You write some data to the disk.
The disk turns off unexpectedly. For example, the device losses power.
In this scenario, the data that you write to the disk is lost.
This issue also occurs when the cluster contains more than two nodes.
This issue does not occur if the SCSI disk supports the SCSI Primary Commands - 4 (SPC-4) standard.
To resolve this issue, install update rollup 2903938. For more information about how to obtain this update rollup package, click the following article number to go to the article in the Microsoft Knowledge Base:
2903938 Windows RT, Windows 8, and Windows Server 2012 update rollup: December 2013
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
For more information about software update terminology, click the following article number to view the article in the Microsoft Knowledge Base:
824684 Description of the standard terminology that is used to describe Microsoft software updates