News for hackers. Stuff that matters.

A comment on One second per second is harder than it sounds. Parent comment

Re:One second per second is harder than it sounds by rachelbythebay on Tuesday July 22, 2014 @12:38AM (#8067413)
Datacenter GPS-backed time sources exist. You can get little boxes which sit in a rack and hook to an antenna and feed nice time to the rest of the place. Those other machines pick it up with ntpd.

The problem is when your system clock is so far out of whack (and/or unpredictable) that even ntpd won't help you. Get enough supposedly-identical machines running and this will probably bite you too.

[ Parent | on HN ]
Re:One second per second is harder than it sounds by kastnerkyle on Tuesday July 22, 2014 @02:36AM (#8067626)
This is 100% true. If you have ever watched ntpd ignore a stratum 0 clock (and every other time source) because some stratum 6 device reports the wrong time, you know the pain. Yes, this isn't supposed to happen, and yes it has happened to me many times.
[ Parent | on HN ]
Re:One second per second is harder than it sounds by feld on Tuesday July 22, 2014 @05:41PM (#8071729)
well, you can override ntpd to always sync no matter how far out of whack but it's not recommended

tinker panic 0

[ Parent | on HN ]