On 2020-Feb-26 16:37:43 +1100, Dewayne Geraghty <dewaynegerag...@gmail.com>
wrote:
>I usually run ntpd with both aslr and as user ntpd. While testing I
>noticed that my server with a direct network cable to my main time keeper,
>jumped from the expected stratum 2 to 14 as follows (I record the date so I
>can synch with the debug log, also below):
>
>vm.loadavg={ 0.09 0.10 0.18 }
>
>Wed 26 Feb 2020 15:16:38 AEDT
> remote refid st t when poll reach delay offset
> jitter
>==============================================================================
> 10.0.7.6 203.35.83.242 2 u 44 64 377 0.147 -227.12 33.560
>*127.127.1.1 .LOCL. 14 l 59 128 377 0.000 0.000 0.000>26 Feb 15:03:40 ntpd[8772]: LOCAL(1) 901a 8a sys_peer <== bad Why is this bad? You've specified that this is a valid clock source so ntpd is free to use it if it decides it is the best source of time. >server 127.127.1.1 minpoll 7 maxpoll 7 >fudge 127.127.1.1 stratum 14 Synchronizing to the local clock (ie using 127.127.1.x as a reference) is almost never correct. What external (to NTP) source is being used to synchronize the local clock? >I'm also very surprised that the jitter on the server (under testing) is so >poor. The internet facing time server is >*x.y.z.t .ATOM. 1 u 73 512 7 23.776 34.905 95.961 >but its very old and not running aslr. The 23ms distance to the peer suggests that this is over the Internet. What sort of link do you have to the Internet and how heavily loaded is it? The NTP protocol includes the assumption that the client-server path delay is symmetric - this is often untrue for SOHO connections. And SOHO connections will often wind up saturated in one direction - which skews the apparent timestamps and shows up as high jitter values. > /usr/local/sbin/ntpd -c /etc/ntp.conf -g -g -u ntpd --nofork ... >I get similar results with /usr/sbin/ntpd, I've been testing both and >happened to record details for the port ntpd. It's probably not relevant but it would be useful for you to say up front which ntpd you are having problems with and which version of the port you have installed. -- Peter Jeremy
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