[SOLVED] Missing/Invisible file on passthroughed unassigned hard disk

[T65]

Dear community,

 

I have different VMs which are connected to the network and some not. I have set up a hard disk with drivers for graphics cards, ... and various programs I want to test in an isolated environment. If I configure a new VM, I passthrough the hard disk (Manual, /dev/disk/by-id/...) and install all necessary drivers from the hard disk without need of the internet.  BUT if I create a text file on the hard disk on VM "abc", shutdown VM "abc" and start another VM "def" - it looks like that this file is not (present/visible/written) on the hard disk in VM "def".

 

The hard disk is only used by one VM at a time! I removed the hard disk and connected it via USB. All data is available, but not always in the VMs. I tried different bus types (VirtIO, SATA, USB, ...), with no success.

 

Does anyone know the problem, perhaps a solution or should I avoid this procedure?

 

Thank you very much,

T65

Edited November 10, 2019 by T65

[T65]

Dear community,

 

I read a little in the "libvirt" documentation and found maybe two useful additions for my issue. I changed the drivers cache and added the following tag to all of my virtual machine XML descriptions.

<disk ...>
  <driver ... cache='none'>
  ...
  <shareable/>
</disk>

In a first test it has already worked - see what the future holds.

 

Thank you very much,

T65