Unifi 6 LR real-time clock

Does the Ubiquiti Unifi 6 LR have a battery backed real-time clock?

I notice it's booting up with a stale timestamp ("Fri Dec 31 16:00:01 1999" in my timezone) so I'm not sure whether to interpret that as not having a battery or some issue with configuring the RTC.

Interestingly, the Ubiquiti Unifi 6 Lite has no such problems.


Just use NTP.

NTP is fine, it was just unexpected behavior.

Briefly: It happens when there is a "false" RTC, without battery.

  • Most routers have no RTC, and the initial time (before NTP kicks in) is taken from files stamps in /etc.
  • Routers with real a battery-backed RTCs do get the proper time from the RTC.
  • But routers declaring a hardware RTC but without a battery (and thus no real time) confuse OpenWrt's logic: OpenWrt reads the time from RTC that just started from its initial time, likely 1.1.2000 0:00 UTC in your case.

Interesting! Where's the logic live? Perhaps it could be improved to recognize sentinel timestamps from volatile RTCs and infer the time from /etc in that case. Booting with timestamps in the distant past could mess with various operations such as certificate validity checks until the NTP client kicks in (assuming the NTP server is even accessible).