Sharing Host Hard Drives in Hyper-V

There are a several ways a host drive can be shared in Hyper-V

1) take host drive offline and attach it as a drive in Hyper-V
This is probably the most efficient from a speed perspective but you cannot access drive on host when it is attached to VM.
Also, you cannot take C drive offline. If you have several drive partitions on a physical drive, they are all offline (or not) at same time.

2) In Enhanced Mode, share a host drive / partition using sharing function in local resources menu.
This uses an interface client called TSCLIENT.



This does not work if guest OS is W10 Home and most non Windows OSs.

3) Use conventional file and folder sharing and set up drives on host as network shares
For Home, this is the best way avoiding method 1.

So what if guest is Pro?
Option 2 is easier as you do not have to mess around with network share, but you can use option 3 if you prefer.

In fact you can do both at same time, but why would you bother with option 3.

Here is where things are a bit strange.

The TSCLIENT interface is really slow. If you copy a large file from the VM to the host, it struggles to copy at as high as 30 MB/s.

If you use conventional networking, it copies at much higher speeds (300 MB/s) on my pc (with nvme drive). You would be limited to c. 100 MB/S if using old HDDs.

If vm was on a remote pc, speed would probably be limited by max wifi or ethernet speed of course.

I tested this on two different devices - same outcome TSCLIENT is slow.

So my conclusion is it is worth setting up networks shares.

There is actually a 4th method which will probably be the fastest of all.

4) Shutdown vm, and mount vhdx file as a drive and copy file with file explorer or Fastcopy/Robocopy.
This is not always the most convenient solution as you can go backand forth betwee using VM or not.


I would really like MS to sort this out - the TSCLIENT mode should be as fast as conventional network settings.