[ntp:questions] Looking for a NTP stratum 2 appliance
mhuff at ox.com
Fri May 26 10:25:20 UTC 2017
You make some good points, but regulations don't always make technical sense. You are correct that we don't need OXCO oscillators, and we could drop that requirement, but it would be a good indicator that the hardware manufacturer isn't just slapping a regular PC together.
Replacing the NIC card on hundreds of servers and in some cases replacing/upgrading blades would be more expensive/time consuming than just purchasing dedicated NTP servers. It is our long term goal especially since we will eventually move to PTP. Our blade chassis at our colo site are already using PTP, just not our core datacenter.
The issues is that sometimes our stratum 2 servers drift away from NIST time (our stratum 2 servers are synced to NIST stratum 1 servers) by > 5 msec, violating FINRA regulations (it's a silly requirement). We are just trying to do our due diligence. I think I could accomplish the same thing by dedicated an OS box for just NTP, but again, if there was an appliance, and cost effective, it would be better.
Matthew Huff | 1 Manhattanville Rd
Director of Operations | Purchase, NY 10577
OTA Management LLC | Phone: 914-460-4039
aim: matthewbhuff | Fax: 914-694-5669
> -----Original Message-----
> From: Miroslav Lichvar [mailto:mlichvar at redhat.com]
> Sent: Friday, May 26, 2017 6:17 AM
> To: Matthew Huff <mhuff at ox.com>
> Cc: NTP Questions <questions at lists.ntp.org>
> Subject: Re: [ntp:questions] Looking for a NTP stratum 2 appliance
> On Fri, May 26, 2017 at 09:35:14AM +0000, Matthew Huff wrote:
> > The OXCO oscillator requirement is for hold-over, but we are looking
> for less jitter in the system. We could strip down the OS machines and
> run only NTP and make other system adjustments that would accomplish
> much of the same, but to dedicated a server just for NTP when an
> appliance is available seems a waste.
> If the stratum-1 servers have stable clocks for hold-over, will OXCO
> on stratum-2 server make much of a difference? Also, why not point the
> clients directly to the stratum-1 servers?
> > FINRA has made new timing requirements that are pushing this.
> Switching to PTP is ultimately the solution, but the switches in our
> core data center don't support it, and would be very costly to migrate
> You might want to consider using NTP with HW timestamping if you have
> servers with NICs that support it. In my experience that usually
> reduces the jitter down to a sub-microsecond level. Unless the network
> is heavily loaded for longer periods of time, it should not be
> necessary to use PTP and expensive switches.
> Miroslav Lichvar
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