Hi Kris, 

I run RHV. RHV is basically oVirt (open source). Once you have the qcow exported from RHV, you can import this into Openstack as an image and deploy it there. I'd suggest that you can deploy oVirt in a single machine and run some tests from there. 
Most of my VMs on RHV I run with a single disk for simplicity reasons mostly. What confuses me about your mail is that you have a Windows VM with /lv and /boot and these sound like unix partitions. Maybe the /boot qcow is where the boot loader resides.. no idea. 

If you can deploy ovirt then you can deploy a windows VM on a single disk then export this and import to Openstack to get familiar which is what I would do in that situation. 

Tip; On any of your disk images you can use `qemu-img info filename.qcow` to get information about the disk image, such as format and size in case it helps. You can also convert this data (such as converting to VHD for Azure) (I am just mentioning this as an FYI).

You probably wont "combine" those files but instead, you would create a VM "profile" that has those three disks. I expect that the vendor was running a VM in RHV with three disks so this is what they have sent to you. 

HTH

Regards,


Tony Pearce


On Mon, 19 Jul 2021 at 13:26, KK CHN <kkchn.in@gmail.com> wrote:
  
QUERY Section A:

We are in the process of   migrating VMs from a Vendor to OpenStack . 

The Vendor has hosted the VMs using  RedHat Virtualization and HyperV around 100 VMs.   Each VM size varies from 50 GB  to 150 GB size. 


What is the best way to migrate these VMs to  New Hardware infra Installed with  OpenStack Ussuri.   

What need to be done at the existing live VMs with the Vendor and in what file format  we have to ask the vendor to give the snapshot of VMs to be migrated ?

I am new to the migration of VMs from a live production  setup ( the present Vendor deployed VMs with all aplications running  on the VM  with   HyperV and RedeHat  KVM. )

We are also using KVM hypervisor.

Kindly advise and direct me with all good practices followed to perform this migration from existing  vendor to our own setup with OpenStack and KVM.

Pls shed some light on this.  

QUERY SECTION B

 Another   question  below

ffor a trail   the existing vendor has given a demo VM,  which is a Windows VM with an ERP application hosted on it .  But the vendor handed over three files of single VM ,  Three qcow2  files. 

They handed over   three   qcow2 files  for this  VM as follows.

1.   First file  is  OS  image as qcow2 

2.   /boot   as    another  qcow2 image

3.   /lv-datat   as  another qcow2  image 

How to combine these files and  we can create a Running VM  from these files and put it on   bare metal installed with   KVM only.  Is this possible ? How ? What need to take care while doing this operation?.

your hints and direcitons highly appreciated.  

Thanks in Advance,
Kris