Struggling to Migrate Windows guests from XEN to Proxmox

[BeDazzler]

I've had issues with the "INACCESSIBLE_BOOT_DEVICE" message when transfering a hw machine to a vm. The issue was resolved by deleting Intels Rapid storage.
I suspect something in the boot process is still looking for a Xen hdd in specific instead of a common (ide) drive.

disk2vhd works fine for migrating vm's but I don't think this will solve the issue since you're still creating a backup of the same disk with Citrix drivers.
Maybe try running the guest agent cleaning tool (on a copy of the vm ofrourse) before migrating it to proxmox:
https://xcp-ng.org/forum/topic/1049/windows-guest-tools-cleaner-tool

hi @mbosma I have used that tool before and it is very handy. I also used that here today to make sure all XEN elements were removed on the VM whilst still running on XEN (ie: before migration). It shows green everything and no XEN elements in the VM configuration.

Now trying the Microsoft disk2vhd conversion tool as per Petr's suggestion.

 

[BeDazzler]

OK, I have figured it out.

I hope this helps someone else with the same challenge.

When starting my migrated XEN VM on Proxmox I was using IDE as per documentation. That doesn't work. Use SATA:0 instead.

Here are the steps I used to get this working:

On XEN Platform:
1) Uninstall XEN Guest Support (Agent, PV drivers, etc) using Windows Add/Remove Programs.
2) Reboot the VM and make it starts without XEN Guest Support.
3) Shutdown the VM.
4) Boot from Win2K12 R2 CD in Repair Mode.
5) reg load HKLM\restore C:\Windows\System32\config\SYSTEM (or wherever your Windows volume appears in repair mode)
6) Search HKLM\restore hive for all occurences of XEN. Delete them.
7) reg unload HKLM\restore
8) Reboot. Allow Windows to start normally.
9) Shutdown the VM.

NOTE1: The XCP-NG has a great utility for checking if all XEN Guest Tools elements have been removed from Windows.
https://xcp-ng.org/forum/topic/1049/windows-guest-tools-cleaner-tool

NOTE2: It is not necessary to run the XEN Guest Tools uninstaller before migrating VMs to Proxmox, you can always boot the Windows CD into Repair Mode and reg load then delete all XEN registry entries manually. This will achieve the same outcome.

On Proxmox Platform:
1) Create new Windows VM with matching hardware specifications. Don't worry about disk settings, we will attach an imported disk.

2) Migrate VM from XENServer to Proxmox:

wget --http-user=root --http-password=bla http://XenHostIP/export?uuid=6408e583-1e92-7521-0e2e-d8b015495816 -O - | tar --to-command=./xva-conv.sh -xf -

3) Rename the migrated image to something more suitable

mv Ref:bla imagename.raw

4) Import the raw disk image into Proxmox storage (adjust command as required for your Proxmox installation):

qm importdisk 101 imagename.raw ZFS-R1

5) Detach the default VM boot disk (if created) and attach the migrated boot volume as a SATA volume, device 0. ** IMPORTANT **

6) Mount VirtIO-Win Support Tools CD.

You can also just download and mount inside Windows from:
https://fedorapeople.org/groups/virt/virtio-win/direct-downloads/latest-virtio/virtio-win.iso

7) Boot the VM from migrated Windows disk (change boot order or ESC to change at boot time if required).

NOTE: You may need to reboot twice if CDROM/DVD drives don't appear.

8) Install x64 support for everything.

9) Shutdown the VM.

10) Create a new (temp) disk using VirtIO, say 10GB in size (only required to get VirtIO drivers loaded and working).

11) Boot the VM.

12) Check Windows Disks and Partitions can see the new VirtIO based disk.

13) Shutdown the VM.

14) Detach the Windows boot disk, re-attach it using VirtIO.

15) Detach the temp 10GB disk. This is no longer required.

16) Enable QEMU Guest Support.

17) Change network adapter to VirtIO PV.

18) Configure boot order.

19) Boot VM.

20) Make sure latest QEMU agent is installed

Download MSI installable from:
https://fedorapeople.org/groups/vir...emu-ga-win-101.1.0-1.el7ev/qemu-ga-x86_64.msi

21) Check VM Summary in Proxmox to ensure driver and QEMU support is running.

22) Adjust TCP Offload and any other network tuning as required.

23) Rejoice, it now works.

** THE END **

Aside from those horrible XEN drivers the problem was setting the correct disk device type for first boot in Proxmox.


D.

 

[Petr Svacina]

Excellent

I am migrating right now few servers Win2008R2 and Win2012 from Xenserver 7.1 to VMware. Same issue with the drivers, but always able to solve point 5. with IDE, but If IDE will not help, try SATA Thanks BeDazzler, for: I will never give up !

 

[mbosma]

I'm glad to see things worked out!!!
Very nice of you to make a quick step-by-step guide, I hope it helps other people in the future.

 

[BeDazzler]

I'm glad to see things worked out!!!
Very nice of you to make a quick step-by-step guide, I hope it helps other people in the future.

Thanks @mbosma . Unfortunately my experience with Proxmox Support was not good. They did not provide any assistance, not even a starting point to resolve the issue, then just closed my ticket without further correspondence.

Whilst I did resolve the issue, the experience has prompted a review and we're now evaluating another platfrom for our migration decision.

D.

 

[martin]

Thanks @mbosma . Unfortunately my experience with Proxmox Support was not good. They did not provide any assistance, not even a starting point to resolve the issue, then just closed my ticket without further correspondence.

@BeDazzler I analyzed your support request and I see this differently. You opened a commercial support request but you reject to pay for this kind of support. So this is not a "bad experience", its just the way it works.

We at Proxmox provide 100 % free software, we provide access to our bugtracker, source code and documentation and we offer even free support via the forum and mailing lists.

The ONLY thing which is not free, is enterprise support. Our team told you exactly this.

Please use either our free offerings or use the commercial support. But please do not request commercial support for free.

 

[BeDazzler]

@BeDazzler I analyzed your support request and I see this differently. You opened a commercial support request but you reject to pay for this kind of support. So this is not a "bad experience", its just the way it works.

We at Proxmox provide 100 % free software, we provide access to our bugtracker, source code and documentation and we offer even free support via the forum and mailing lists.

The ONLY thing which is not free, is enterprise support. Our team told you exactly this.

Please use either our free offerings or use the commercial support. But please do not request commercial support for free.

Hello Martin,

Thank you for the reply.

The purpose of migrating a XEN guest to Proxmox was to evaluate the platform and include it for our decision path to migrate approx. 220 servers across 5 locations. I am a platform architect leading a small team who are evaluating 3 vendor product offerings.

When the XEN guest was not able to function on Proxmox I turned to Proxmox for some very basic assistance. Unfortunately Proxmox Support did not assist without a subscription at considerable cost.

There is no need for a potential customer to endure the cost and burden of a subscription when we had not yet made a decision on Promox since this was an evaluation.

Further, as it turns out, the issue was not with XEN or our guest VMs, it was with the way in which Proxmox sees the disk system on the VM.

Getting back to your other comment regarding "free support via the support forum" which Proxmox Support did tell me to follow, the documentation on both your support pages and in forum posts was incorrect since it was for a different release of the products we are working with.

So the net problem here, Martin, is that we required assistance during an evaluation task, for which Proxmox Support was not prepared to offer without substantial commitment.

That's the key issue here and in my opinion Proxmox cannot expect a potential customer in the pre-sales phase of a transaction, to agree on a subscription, especially since there was actually nothing wrong with our guest VMs.

I will leave that with you to think over for your next potential customer.

If you want to speak with me about this, feel free to touch base privately.

D.

 

[martin]

Hello Martin,

Thank you for the reply.

The purpose of migrating a XEN guest to Proxmox was to evaluate the platform and include it for our decision path to migrate approx. 220 servers across 5 locations. I am a platform architect leading a small team who are evaluating 3 vendor product offerings.

When the XEN guest was not able to function on Proxmox I turned to Proxmox for some very basic assistance. Unfortunately Proxmox Support did not assist without a subscription at considerable cost.

There is no need for a potential customer to endure the cost and burden of a subscription when we had not yet made a decision on Promox since this was an evaluation.

Testing is the right approach and no one will charge you for this. We assist via the community channels (Forum, Mailing lists).

Further, as it turns out, the issue was not with XEN or our guest VMs, it was with the way in which Proxmox sees the disk system on the VM.

Getting back to your other comment regarding "free support via the support forum" which Proxmox Support did tell me to follow, the documentation on both your support pages and in forum posts was incorrect since it was for a different release of the products we are working with.

So the net problem here, Martin, is that we required assistance during an evaluation task, for which Proxmox Support was not prepared to offer without substantial commitment.

No, you just contacted the wrong team - which we told you. Please ask your questions on the right place and do not tell others that our support is bad, that just not fair.

I know that you can get pre-sales from commercial license vendors, but you have to pay for this afterwards (purchase a license). Proxmox is free software, so you never pay for the license, we sell commercial support and services only as an option if you need it for your production setups.

That's the key issue here and in my opinion Proxmox cannot expect a potential customer in the pre-sales phase of a transaction, to agree on a subscription, especially since there was actually nothing wrong with our guest VMs.

I will leave that with you to think over for your next potential customer.

If you want to speak with me about this, feel free to touch base privately.

D.

 

[BeDazzler]

Testing is the right approach and no one will charge you for this. We assist via the community channels (Forum, Mailing lists).



No, you just contacted the wrong team - which we told you. Please ask your questions on the right place and do not tell others that our support is bad, that just not fair.

I know that you can get pre-sales from commercial license vendors, but you have to pay for this afterwards (purchase a license). Proxmox is free software, so you never pay for the license, we sell commercial support and services only as an option if you need it for your production setups.

Pre-sales customers will be more likely to purchase if they feel welcome and when support staff are genuinely interested in assisting with problem resolution.

If you have no ability to provide support without charge, at least review the amount charged - ie: create a once-off assistance type support ticket that does not require a subscription for services that may never be taken up.

 

[logiczny]

Migration from ANY version Xenserver to ANYWHERE (proxmox, vmware) is PURE HELL.

You must follow exactly this:

https://support.storagecraft.com/ar...m-thread-exception-not-handled?language=en_US

Migrate LVM, VHD from xen to proxmox. This should be okay.
Start VM and you will get BSOD. That is OK. Boot to recovery, in recovery mode:

1. Do this:

Use administrative command prompt and navigate to C:\windows\system32 directory.
DIR Xen*.*
DEL Xen*.*

Navigate to C:\windows\system32\drivers directory.
DIR Xen*.*
DEL Xen*.*

2. Do this:

You are in the Windows PE based Recovery Environment.
Open a command prompt by going to Tools > Command Shell
Load the Windows System registry hive from the boot volume.

reg load HKLM\restore c:\Windows\System32\config\SYSTEM

Run regedit.exe from the command prompt.

Browse to following registry locations. There maybe multiple keys with that name. Look through them to find UpperFilters keys with the value XENFLT: (THIS IS MOST IMPORTANT OF ALL THE MIGRATION !!!)

Examples:
HKEY_LOCAL_MACHINE\restore\ControlSet001\Control\Class\{4d36e96a-e325-11ce-bfc1-08002be10318}
HKEY_LOCAL_MACHINE\restore\ControlSet001\Control\Class\{4d36e97d-e325-11ce-bfc1-08002be10318}

Right-click the UpperFilters key with the XENFLT entry and click Delete.
For the remainder of the keys, search the registry (Ctrl+F) and search for UpperFilters -> XENFLT.
Remove any keys mentioning XenFLT. Use F3 to search for the next instance.

Remove competely:

HKEY_LOCAL_MACHINE\restore\ControlSet001\Services\XEN
HKEY_LOCAL_MACHINE\restore\ControlSet001\Services\xenbus
HKEY_LOCAL_MACHINE\restore\ControlSet001\Services\xendisk
HKEY_LOCAL_MACHINE\restore\ControlSet001\Services\xenfilt
HKEY_LOCAL_MACHINE\restore\ControlSet001\Services\xeniface
HKEY_LOCAL_MACHINE\restore\ControlSet001\Services\xenlite
HKEY_LOCAL_MACHINE\restore\ControlSet001\Services\xennet
HKEY_LOCAL_MACHINE\restore\ControlSet001\Services\XenSvc
HKEY_LOCAL_MACHINE\restore\ControlSet001\Services\xenvbd
HKEY_LOCAL_MACHINE\restore\ControlSet001\Services\xenvif

Close Registry Editor and unload the hive:

reg unload HKLM\restore

Reboot. Your Windows 7/8/10/2008/2012/2016/2019 will normaly boot ....

3. Do this: Uninstall xentools / agent from the add/remove programs ....

In my case, I was searching for "XENFILT", because no "XENFLT" was found.

 

[Petr Svacina]

I suppose XENFLT is typing error Sorry for confusing. But you did the trick

 

[Petr Svacina]

To BeDazzler: Sorry man, I was using Citrix xenserver for the years and this is definitely Citrix error. Their VM drivers are the pain in the ass and has this issue over the hypervisors world. KVM drivers (virtio) are clean and simple and works at least So it is hard to solve problem here, as we are talking about Citrix issue, not about PVE or KVM problems ...

That is my opinion, and without my experiences with Citrix and PVE I was not able to help either

 

[Hanzl]

so i went through this way this week, found many helpful resources, but no complete guide.... maybe this will help someone

https://github.com/hnzl62/xen-to-pve