Unable to recognize the volume from the Windows OS after restarted the virtual server.

By setting the Windows storage area network policy, it is always on-line, so it may be possible to avoid it.

Steps to avoid
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1: Open Command Prompt
2: Type "DISKPART.EXE" and press ENTER
3: Type "san policy = OnlineAll" and press ENTER
4: Type "exit" and press ENTER, to exit Command Prompt
5: Bring the relevant disc online on the Server Manager screen
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Regarding the disk (volume) connected after the above execution, operation 5 is unnecessary, and it becomes online state from the time of connection. Regarding the storage area network policy, we are sorry to trouble you, but please refer to the following.
https://technet.microsoft.com/en-us/library/gg252636(v=ws.10).aspx