[ntp:questions] Re: asyncronous path between "time client" and ntp server

Bob Beers bob.beers at gmail.com
Wed Oct 12 16:19:42 UTC 2005

On 10/10/05, Danny Mayer <mayer at gis.net> wrote:
> Bob Beers wrote:
> > BTW, I really meant asymmetrical, not asynchronous, but the former
> > would likely imply the latter.
> >
> Not at all. They're unrelated and orthogonal to each other. How do you
> know that the path is asymmetric? Do you have any evidence to back this
> up? If so can you estimate the amount of this asymmetry? There is at
> least one handle you can use to tell ntp about the asymmetry but I'd
> have to look it up. It's more important to look at the evidence first.
> Thanks again for the replies. The more questions I ask the more
questions I need to ask. I may have to quit while I'm behind. :)

I used traceroute from ntp server to ntp client and vice versa to
come to the conclusion that the path between the two was not symetrical.
Do you need to see the traces? There are several identical 192.168.20.
subnets being NAT'd, and a 192.168.0. subnet where the ntp server
is being NAT'd, but this subnet is not behind a satellite link.

Anyway, there has been an alternate time server provided which is not
NAT'd. (I hope it is ntpd, but I haven't confirmed)

The ntp client box is happy:

from ntp.log:
12 Oct 16:00:06 ntpd[11773]: synchronized to<>,

bash-2.05# ntpq -p
remote refid st t when poll reach delay offset jitter
* <> <> 3 u
442 1024 377 820.045 209.971 71.973
bash-2.05# date
Wed Oct 12 16:07:49 UTC 2005

So, for now, I withdraw the question, but I'll keep reading the docs and
keep lurking on the mailing list.



More information about the questions mailing list