Hyper-v passthrough drive smart problem

Question

Hello,

I would like to pass through a hard drive to a virtual machine and I have seen that the smart information doesn't work. My machine is a Win11 Pro

Is there something I do wrong? Or an option to allow it to work?
I tries do pass my controller directly to the VM (SAS integrated card) but I have an error when starting the Virtual machine (ressource not available) so I guess the motherboard uses a shared PCIe port for the integrated SAS card

Is there a possibility to receive the smart information on the host to tell the problems to the guest?

Thank you

Answer 1

Hi Marc,

Hope you're doing well.

When you pass through a hard drive directly to a virtual machine (VM) in a hypervisor environment like Hyper-V, certain functionalities such as SMART (Self-Monitoring, Analysis, and Reporting Technology) information might not be accessible within the VM. This is because the hypervisor abstracts the underlying hardware and presents it to the VM, which may limit direct access to hardware-specific features.

Here are some considerations and potential solutions:

1. When you pass through a hard drive directly to a VM, the VM gains direct access to the disk, but this can prevent the host from accessing it. SMART information is typically accessed at the hardware level, so the VM might not be able to retrieve it.
2. If your motherboard or storage controller supports it, you might be able to access SMART information from the host system and then share it with the VM. This could involve setting up a mechanism to periodically retrieve SMART data from the host and pass it to the VM through a shared folder or network connection.
3. Instead of passing through the physical disk, consider creating a virtual hard disk (VHD or VHDX) on the host system and attaching it to the VM. This way, the disk is virtualized and managed by the hypervisor, allowing the host to access SMART information and pass it to the VM if necessary.
4. There are third-party monitoring tools available that can monitor disk health and SMART attributes on both the host and guest systems. These tools typically operate at the software level and can provide insights into disk health without requiring direct hardware access.

It's worth noting that passing through hardware directly to VMs can be complex and may require specific hardware support and configuration.

Best Regards,

Ian Xue

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Answer 2

Hello,

I have tested with a software (Crystal Disk) on the host and I can retrieve the information I need. It is not perfect but at least i have a mail when there is a problem with the smart.

Creating a VHD is not possible for me (I plan to use ZFS in a virtual machine so i need access to the real hard drive (until REFS is really ready for normal use).

Thank you