[tz] New Yorker article on David Mills and NTP

Steve Summit scs at eskimo.com
Tue Oct 4 17:20:14 UTC 2022


Fred Gleason wrote:
> I suspect that one of the primary reasons that such time resets
> have been so fraught [...] is their relative rarity [...] deployed
> systems rarely have to cope with one and thus get the inevitable
> bugs identified and shaken out.
>
> It would almost be beneficial if such an event would occur at least
> once per annum, to allow the 'reset' logic to be regularly exercised.

A few years back I did a bunch of work (sadly as yet unpublished)
trying to improve support for leap seconds, and one of the things
I wrote was a mock NTP server serving time on hundreds of
different test ports, with each port offering fake leap seconds
on a different day.  So, theoretically, if you wanted to test
your system's leapsecond handling, all you'd have to do was pick
the right port and you could have your leap second tomorrow.

(Unfortunately it wouldn't have been nearly as convenient to use
as I had anticipated, because it turns out that stock ntpd doesn't
offer an easy way to configure an upstream server connection on
other than the default port 123.)


More information about the tz mailing list