topic Re: Hyper-V over SMB implementations in Microsoft Virtualization Discussions

Hyper-V over SMB implementations

NetApP_3260 — Wed, 04 Jun 2025 09:49:54 GMT

Hi Everyone We have hyper-v workload hosted on NetApp CIFS.

The datastore share was configured with continuous availability.

We analyzed the open files from NetApp cli and found that only vhdx files are protected with continuous availability.

There are some files which are showing as not protected with VMCX and VMRS extensions.

Is this the correct state?　Shouldn't all files be CA protected?

Re: Hyper-V over SMB implementations

ChanceBingen — Tue, 25 Apr 2023 13:19:46 GMT

I've also noticed that, and it appears to be the correct behavior. In essence, the Windows SMB client has not requested persistent file handles on those files.

It makes sense, those are the only files that need to sustain IO across a storage failover event.

Re: Hyper-V over SMB implementations

johneasty — Tue, 25 Apr 2023 13:50:55 GMT

VMCX files (smilar to VMC files) are used by Windows Explorer to provide information about the VM in the Explorer window. I don't see why it would need protecting, it sits in the \virtual machines directory under each user, so not user file that would have a session open to it.