ntp problems stratum 2 to 14?

[Peter Jeremy]

On 2020-Feb-26 16:37:43 +1100, Dewayne Geraghty <dewaynegeraghty at 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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