[ntp:questions] R: Re: debugging strange ntp in virtual environment

Rob nomail at example.com
Thu Sep 19 20:20:37 UTC 2013


unruh <unruh at invalid.ca> wrote:
> On 2013-09-19, Horvath Bob-BHORVAT1 <Bob.Horvath at motorolasolutions.com> wrote:
>>
>>
>>> -----Original Message-----
>>> From: questions-bounces+bob.horvath=motorolasolutions.com at lists.ntp.org
>>> [mailto:questions-bounces+bob.horvath=motorolasolutions.com at lists.ntp.org] On
>>> Behalf Of Rob
>>> Sent: Thursday, September 19, 2013 11:20 AM
>>> To: questions at lists.ntp.org
>>> Subject: Re: [ntp:questions] R: Re: debugging strange ntp in virtual
>>> environment
>>> 
>>> Horvath Bob-BHORVAT1 <Bob.Horvath at motorolasolutions.com> wrote:
>>> >
>>> 
>>> Why?
>>> What we have is a similar situation, we had a physical machine providing ntp
>>> service to the network and we went to virtualisation.
>
> Why why why would you want to do that? It is simply nuts. 

Because the boss wants to cut down on physical machines, as we are
migrating to external hosting.

Unruh, what we see time and time again: you as a hobbyist on your own
little PC at home have a completely different view on the world than the
corporate sysadmin has.

You are always recommending things that just aren't practical.
Just as I can't get a Sure GPS board and install its antenna outside
the building with a long wire to the computer room, I also cannot decide
if we will virtualize or not.

We virtualized about 30 servers into 3 boxes at one location, and 4
servers into another box at another location.  The footprint went from
a room full of equipment to 6HE in a rack.
Having a few hundred us less NTP accuracy is a small price to pay for
that.

If only you would understand such things...

>>> The machine still providers good time.  It is still synchronized to time
>>> sources on the network as it was before, and it still provides time to other
>>> servers and clients on the local network.  Servers are other virtual servers
>>> on the same ESX hosts.  Loading of the origin time servers is the same.
>
> It seems to now, and then that machine becomes loaded, with one of the
> other virtual machine taking up loads of time, and suddenly your time
> has gone to hell. This is how you want a server to behave?

You have zero knowledge of how ESX behaves.
Probably you base your opinion on a VMware workstation installation you
once did on your hobby PC.
Please don't make statements about stuff you have not the slightest
knowledge of.

> Sure it works since you test it on a lightly loaded machine where each
> OS gets approximately the same amount of time. 

And also when it is loaded.  That is why you have an 8-core machine
underneath it, and a virtualization platform that allows you to allocate
resources.



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