Highly accurate system time

On Time for All Time

Article from Issue 203/2017
Author(s):

After the idea of procuring an atomic clock failed to thrill the other members of Charly's household, our intrepid columnist simply decided to tap into the timekeeping of a GPS satellite. In doing so, he ensured the kind of punctuality at home that only large data centers actually need. Precisely.

The network time protocol (NTP) is one of the easiest server-based services to configure. The ntp.conf file requires minimal configuration; just one line with a source from which to tell the time.

pool de.pool.ntp.org iburst

You usually specify more than one source. The NTP daemon (ntpd) queries it cyclically and tries to compute running time differences caused by network latency. My local NTP service runs on a Raspberry Pi (Rasp Pi), otherwise employed full-time in driving the garden irrigation system, and has a time imprecision of 30 to 40msec.

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