Migrating Windows NT from VMware

[unsichtbarre]

Howdy,

I am involved in a POC to potentially migrate several Windows NT workloads from vSphere 8.x. These are industrial workloads and there is no possibility of upgrading beyond NT. Now the user has deemed VMware unacceptable under Broadcom and seeks alternatives.

Originally, it looks like these NT systems were physical (Compaq) and then P2V to VMware (a long time ago). There is a single orphan SCSI disk (BusLogic) which is not seen by the OS and four IDE disks which comprise the boot and all data disks.

I Have been able to migrate the NT VMs to a POC VMware environment, where they boot and run acceptably. I can pre-load drivers under VMware (such as: LSI 53C895A and BusLogic), however noting I do makes any SCSI disk visible to NT for some reason.

Under PVE, the SCSI disk is seen by the boot manager, however, I get a "error loading operating system" if I choose the IDE disk where the bootloader is located.

• Pentium
• LSI 53C895A

I have primary reference here: https://blog.pipetogrep.org/2025/05/23/how-to-install-windows-nt-4-server-on-proxmox/

Any ideas?

THX,
-JB

 

[bbgeek17]

Today must be “remember the old times” day https://forum.proxmox.com/threads/winxp-refuses-to-boot.172058/#post-801693
Just waiting now for an OS/2 Warp question ;-)

On a more serious note: digging deeper into the memory banks, if I recall correctly, NT4 had a pretty strict boot loader string that wasn’t very forgiving when moving disks across controllers. You may need to experiment with ISO recovery booting and editing the boot.ini file.

Similar to the XP thread, I’d suggest installing a fresh NT4 VM first to confirm a baseline working configuration. That gives you a target to strive for when converting an existing system. You can also try various controllers on fresh boot which will indicate to you whether such combination of driver/controller is viable. This would take away the ambiguity of whether the failure is tied to a particular way the production VM was set up.

Good luck!

---

Blockbridge : Ultra low latency all-NVME shared storage for Proxmox - https://www.blockbridge.com/proxmox

 

[LnxBil]

Such old systems could potentially be virtualized twice in order to run on other hypervisors. First would be some older VMware player setups that runs on linux on PVE. I haven't done this, but also switchting to VirtualBox could be possible. The support for NT4 and also OS/2 is much better there.

 

[_gabriel]

I remember a case while virtualizing a physical NT4 from HP Vectra.
Thanks to pre Windows Vista , install/repair booting from CD over an existing Windows was possible and saved days many times.
HAL.dll was from HP locked to their hardware, which prevents boot (was in VMware workstation).
Replaced with the vanilla, then boot fine.
Finally, cancelled because found an old GPU which revived the 20 years old box then driving an industrial label printer.

EDIT: Was HAL.dll locked to HP hardware instead NTLDR.