[ntp:questions] running NTP as server only

Maarten Wiltink maarten at kittensandcats.net
Thu Aug 19 16:07:41 UTC 2010


"unruh" <unruh at wormhole.physics.ubc.ca> wrote in message
news:slrni6qdub.fcq.unruh at wormhole.physics.ubc.ca...
> On 2010-08-19, Rob <nomail at example.com> wrote:
>> unruh <unruh at wormhole.physics.ubc.ca> wrote:
[...]
>>> uh, to quote Landauer, all information is physical. All virtual
>>> machines MUST also run on physical machines.
>>
>> But that does not mean you can run NTP on them.
>>
>> E.g. on VMware ESX, you cannot do this.
>> (there is an NTP running on the console session, but that is just a
>> virtual machine running a Linux variant, it is not running on the
>> physical machine either)
>
> An OS on a physical machine running virtual servers really should
> be able to discipline the physical clock on the  system. It is like
> saying that the physical machine has no way of accessing disks.Control
> of physical hardware ( and I consider clocks physicsl hardware) should
> be the responsibility of the base OS. But my strictures probably do
> not help you.

Of course the physical machine has ways of accessing disks, and the
clock, and everything it needs to virtualise. Those ways need not look
anything like the ways it then gives to VMs.

Hypervisors have gotten more bare-bones over the years. They are no
longer complete OSes; it's not needed _for a hypervisor_. If you want
a compete OS, you can run it in a VM. It's a logical step.

Groetjes,
Maarten Wiltink





More information about the questions mailing list