Sandeep Aggarwal

Imp: Command Device & Hyper-V VM

Discussion created by Sandeep Aggarwal on Jul 16, 2014
Latest reply on Nov 3, 2017 by Karan Patani

Hello Everyone,


Just wanted to share some knowledge. Not sure if you had come across such setup. Please provide your feedback accordingly.


We are building a Microsoft private cloud using Hitachi converged platform solution. We need to build management server VMs on Hyper-V Cluster for Hitachi Command Suite applications.


As a result, we had to provision command device to management VM for Hitachi Tuning Manager.


There were 2 options:-


1) Using VFC Adapter (thru NPIV)  - it is only supported by Microsoft on Windows 2012 R2. else it might work occasionally but will never be stable and bring down the VM abruptly.

2) Using Pass Through Disk - When you map the command device to Hyper-V cluster and mount it as "Physical" device to VM, it will show 2 abrupt things.

a) in Hyper-V Cluster, it will NOT allow you to add disk successfully. It will always failed and claim that resource busy. Microsoft cluster do not support command device as cluster resource.

b) once mapped to VM, it will show as "read only" device in disk management of VM.


The Solution to the problem is that


do not add command device as cluster resource and keep VM out of cluster and hosted on a single host.Then, all things will work just fine as expected.


At any time, you can do live migration of VM from 1 host to another manually.


I hope this will help fellow community champs.