NTPsec leap second experience

[Jason Azze]

On Mon, Jan 9, 2017 at 2:27 PM, Matthew Selsky
<Matthew.Selsky at twosigma.com> wrote:
> On Sat, Jan 07, 2017 at 05:36:14PM -0500, Jason Azze wrote:
[snip]
>> Dec 31 18:59:59 harbormaster ntpd[6653]: SHM: stale/bad receive time, delay=-1s


> Do you know the source of the SHM error message in your logs?
>
> My classic ntpd stratum-1 clocks reported the "kernel reports leap second..." line twice (maybe a bug?), but there were no SHM errors.

No I don't. I was wondering if it was expected behavior or not.

I discovered that weekend that the cheap USB GPS that I have attached
to that machine (a VK-172 with a Ublox-7 chip) doesn't ship PPS like I
thought it did, so the SHM mailbox had access to only the much less
desirable SHM(0) GPS refclock. In fact, I have this particular machine
set up with the SHM and three of Gary Miller's RPi servers as peers.
All of Gary's machines were serving up better time than my GPS, which
had been thrown out as a false ticker!

That's my roundabout way of suggesting that it's possible this
machine's result is an edge case (or maybe more accurately a corner
case with leap second + false ticker SHM being the two parameters).

-- 
Regards,
Jason Azze