[Info-vax] WHY IS VSI REQUIRING A HYPERVISOR FOR X86 OPENVMS?

[Andrew Brehm]

On 31/12/2020 23:35, Snowshoe wrote:
> On 12/31/2020 1:50 PM, D W wrote:
>> On Thursday, December 31, 2020 at 12:07:41 PM UTC-5, Andrew Brehm wrote:
>>> On 21/12/2020 02:03, Michael C wrote:
>>>> 2ND PROBLEM - JOINING THE LINUX PATCH OF THE DAY CLUB
>>>>
>>>> HERE IS THE OPENVMS CERT COUNTS AS OF 2018 COMPARE THEM WITH OTHER 
>>>> OSs - SEE THE PROBLEM?
>>>
>>> No, I don't see the problem. How would Linux patches affect OpenVMS
>>> running in a virtualised environment?
>>>
>>> I'm not sure you understand virtualisation correctly.
> 
> Is there such a thing as an OS-less VM hypervisor? More specifically, a 
> hypervisor which is its own OS in a way, you boot it directly (not 
> booting Linux/Windoze then starting the hypervisor) and pretty much the 
> only thing you can do once booted is starting virtual machines.

Yes.

VMware vSphere works like this, it's a type 1 hypervisor (runs directly 
on the hardware and not on another OS).

Technically Hyper-V and Xen are also type 1 hypervisors but they both 
use a VM running Windows or Linux or NetBSD respectively for driver support.

Oracle's and IBM's hypervisors for SPARC and POWER also run directly on 
the metal.

> I suspect this is the case but I am not familiar with hypervisors.
> I also suspect that many/most/all are really Linux under the hood.

KVM runs on Linux, Xen uses Linux or NetBSD for drivers.

Hyper-V uses Windows for drivers.

vSphere runs directly on the metal and has its own driver architecture.

Bhyve runs on FreeBSD.

-- 
Andrew Brehm