[135338] in North American Network Operators' Group
Re: anyone running GPS clocks in Southeastern Georgia?
daemon@ATHENA.MIT.EDU (Robert E. Seastrom)
Fri Jan 21 17:38:28 2011
To: Gary Buhrmaster <gary.buhrmaster@gmail.com>
From: "Robert E. Seastrom" <rs@seastrom.com>
Date: Fri, 21 Jan 2011 17:37:46 -0500
In-Reply-To: <AANLkTim=Rks3MH+ySoYHYKaauZkhgV1-xJ05wXLxi=wE@mail.gmail.com>
(Gary Buhrmaster's message of "Fri, 21 Jan 2011 21:45:59 +0000")
Cc: nanog@nanog.org
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
Gary Buhrmaster <gary.buhrmaster@gmail.com> writes:
>> NTP isn't going to be the only "ripple".
>
> Most of the "brand name" GPS NTP solutions have a clock
> with is more than stable enough to survive without GPS
> lock for 45 minutes(*). Some of the more expensive units with
> temperature controlled oscillators have hold times in the
> many weeks. My guess is that the NTP ripples will be
> limited to those NTP servers just (or recently) booted
> which have not yet achieved a stable clock state.
>
> Gary
>
> (*) This presumes that this test results in loss of signal
> lock, and not intentionally injected false information.
Seeing the ripples also presumes that people are monitoring their NTP
system health more closely than just looking at the output of ntpq -p. :)
-r
