Our customer has an Teltonika NTP001 and we’re trying to make all the devices in their network sync to one source.
We ran into some issues with the GPS/GNSS signal being unreliable (for possible various reasons currently…) and when the signal is gone, the sync seems to not work at all, leaving the devices in the network unsynced.
Is there any way we could allow the NTP001 to work as an NTP server and let clients sync the time from it even when there is no GPS/GNSS signal?
For this client of ours, it’s more important that all devices’ clocks are synchronized with each other than that the synchronized time is highly accurate.
Just another one that had to solve this kind of situations, you should consider if you can run these equipment NTP-service and configure each to act to others in “peer” mode instead of of “server” to a single NTP source.
As a general rule you always should have more than one single NTP-time source configured for devices. NTP is a sophisticated protocol in many ways and it elects best most reliable, consistent and with least varying jitter etc. time source always when enough sources are available to it. Thus a good principle is to have at least three NTP time sources configured available and let NTP implementing daemon select best from those where to sync from.
Thus instead of trying to rely only Teltonika GNSS/NTP only time source, I would suggest you try to get at least two more NTP sources to setup. Those could be further away your private network or even over public internet if that is permitted and by the book implementation there where you work. But if not then you should consider installing two small PC’s where you run some applicable OS (stable version installed from reliable approved source) like Debian, OpenBSD or like. You can make these your secondary time sources local net or further up in your private network running ntpsec, chrony or openntpd. You configure these “peer” to each other and then sync you devices from all three.
Depending our environment I would suggest you check Intel NUC PC:s, and applicable choose industrial models that is what environment requires.
This is a one proper way to improve your time source reliability. I’ve set up it several of times and did maintained it quite long time for one of my previous employer. I’ve recently retired, so I’m not doing it any more but did it over 25 years total there. Same kind of was used internally when I was couple of years stint working for a very large national telecom EMEA southern region. We did have there atomic clocks also at RBOC’s, but to keep remote smaller sites services sync and not to drift too far during outages due weather conditions or something else there was a way needed to be implemented. There was no need to use additional PC servers, we just ran NTP “peer” mode with our site HP management servers.
And sure if NTP doesn’t cut ever with it’s accuracy or some other reason one solution is to use PTP multicast LAN service and sync clients listening that and keeping them in sync.
riku