nanog mailing list archives

Re: Leap second tonight


From: Ask Bjørn Hansen <ask () develooper com>
Date: Mon, 16 Mar 2009 23:07:42 -0700


On Dec 31, 2008, at 15:28, Kevin Oberman wrote:

We use CDMA clocks and last leap second it took weeks for all of the
cell sites to adjust the last one. As a result, I have set all of our
clocks for manual leap second and set them to adjust tonight at midnight
(UTC).I'll take a look in about 35 minutes and see how it worked.

Chiming in a little late here ...

Over at the NTP Pool we had about 9% of the servers not handle the leap second accurately; starting at midnight UTC. After an hour (so between 01:00 and 02:00) it was down to about 3%; a couple hours later down to about 1% of our servers (a few dozen)[1]. Most of those got in order within 24-48 hours. Interestingly the few who didn't get corrected within a few days were, tada: CDMA clocks.

To stay vaguely NANOG on-topic: I believe at least some of our ~1700 NTP servers are routers; so I'm guessing they handled the leap second alright.

Sounds like a "RISKS" lesson: Don't use side-effects of a tool for something critical. (If I understand it right then CDMA uses accurate time because it needs accurate frequency; not because it cares what time it is).

Also: Who came up with having the leap second on New Year!? Clearly not someone with any operational experience.


 - ask

[1] http://fortytwo.ch/mailman/pipermail/timekeepers/2009/004619.html and http://fortytwo.ch/mailman/pipermail/timekeepers/2009/004623.html

--
http://develooper.com/ - http://askask.com/




Current thread: