[chrony-users] Help with GPS timesync/config

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My scenario: I have a beablebone black with a GPS module. I can get some stability but I need some guidance on cleaning up my config/design. One behavior that I'm seeing is that gpsd is creating /dev/pps0 though it appears unusable.  ppstest returns time_pps_fetch() error -1 (Connection timed out). I configured the device tree to pickup pps off of the GPIO and that does work though I get the clear 0, seq 0, which another post highlighted as a kernel bug (source 0 - assert 1585167111.891016501, sequence: 19101 - clear  0.000000000, sequence: 0).

Never the less, this configuration does work though it's not as stable as I'd like as.  I get the "Can't synchronise: no majority" error from time to time. chrony indicates "time in error", then after a bit it reestablishes. It's worth noting that this solution is for off-grid use and will never be able to see network time as a source.

My questions are:
Can I improve my configuration settings?

Since I'm technically offline is there any option for a third time source (an earlier thread noted this can resolve the no majority issue). Would an external RTC help?

Config file:
keyfile /etc/chrony/chrony.keys

driftfile /var/lib/chrony/chrony.drift

logdir /var/log/chrony

log statistics tracking refclocks tempcomp

maxupdateskew 100.0


makestep 1 -1

refclock SHM 0 refid GPS precision 1e-1 

refclock PPS /dev/pps1 lock NEMA



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