OpenMarine

The use case, creating an offline NTP, was that I'm on our boat sometimes don't have an Internet connection but always have a connected GPS. The GPS updates time on a Raspberry(RPi) running OpenPlotter/Signal K.

The actual issue is that there are other devices on the LAN that needs to be updated and then you have to set up an NTP server.
Of course this setup is also valid for a RPi/server, with a RTC, acting as a NTP server in an isolated LAN.

Did a post handling the subject https://pysselilivet.blogspot.com/2021/0...fline.html

/Mats

That is interesting. I have wondered about this issue and you have a solution. I'll be sure to check this out later...

Thanks for sharing!

tinypilot does this as well

https://github.com/pypilot/pypilot/tree/master/scripts

there are both bash and python scripts for setting time and date from gps