[ntp:questions] Use ntp orphan mode to sync time two stand-alone computers

Miroslav Lichvar mlichvar at redhat.com
Mon Aug 15 09:38:26 UTC 2016

On Sat, Aug 13, 2016 at 09:28:52PM -0400, Jason Beach wrote:
> I have two arm-based Linux (ubuntu 14.04) computers, a Jetson TK1 and TX1
> that will fly on a multicopter and hence have no internet connection (they
> are networked together onboard).  They also do not have RTC's built-in but
> I have added a smll external one (https://www.adafruit.com/product/255) to
> the Jetston TK1.  The TK1's time gets set on boot from this RTC no problem
> (using a `sudo hwclock -s -f /dev/rtc0` in rc.local).  I am trying to get
> the TX1 to sync to the TK1's time using ntp.

If you need to sync one machine to another, you should use the LOCAL
driver ( and not the orphan mode. Orphan mode is for cases
where a server should be automatically selected from a group of
unsynchronised servers. In your case only machine can be a server (the
one with RTC).

Miroslav Lichvar

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