On-Board GPS

We have a lot of AP's that go to on-board GPS, when you login to the AP you see that its receiving Canopy Sync on the Main Power port. Why do the AP's not switch back to the Main/Power port when they start to recieve sync again?

We use PacketFlux Sync Injectors:

450i, 450m and ePMP 3000's we use:


450, ePMP 1000/2000's we use:


We use PacketFlux GPS's (depends on the site):




Any help would be appreicated.

There is no logic to "switch back", or to prefer any given source of GPS. If the radio is receiving sync from any source without error, it will continue to receive from that source.  Does this create issues for you?

On occasion we have seen SM's losing session even tho they have good modulation/RSSI and a AP reboot fixes it. I just assumed that having all your AP's on the same sync source would be pefered.

In theory, the pulse should be the same and transparent regardless of source. What version of software are you running on your devices? We had cleaned up some of the GPS signalling in a software version in the not-too-distant past.

So I've experienced this and it's really frustrating. Basically, if you're running 450's or 450i's and providing 'Canopy Sync' to them, and running at gig-ethernet you're going to have problems. Canopy Sync was not designed to signal over gig-eth... that's why Cambium Sync was introduced. If you want to run gig-e (or provide sync to 450m's) YOU HAVE TO USE Cambium SYNC! Other things that mess with ethernet sync are inline ethernet lightning arrestors. We've on occasion had to remove these from an AP that just could not get a reliable % of pulses. Presto... it's at 100% now.

We've also found that with older PacketFlux devices it's hard to troubleshoot sync or GPS lock issues... that's why we've moved over to the RackInjectors w/the newer modules that support GPS+GLONASS. This combo gives you way way more satellites to lock onto. The new Rackinjector firmware and GUI makes it so much easier to tell what's going on with your satellites. If your sync source looses satellite lock, then the older 450's will try to use it's integrated GPS module (iGPS) and never switch back over to the ethernet sync source. iGPS was never really reliable and thus it was recommended that it not be used, and was not included in newer 450 AP's. The only way to get an AP to switch back to an eth sync source is by rebooting it OR using the CLI:

  1. Telnet+> synconboard
  2. On-board Sync is on
  4. Telnet+> synctimingport
  5. Sync over Timing Port is on
  7. Telnet+> syncpowerport
  8. Usage: syncpowerport <on>/<off> <camb>
  9.  No params:            Show current status
  10. on or off (optional): Enable or Disable Canopy Sync
  11. camb (optional):      Enable or Disable Cambium Sync
  12. Requires on/off parameter first, e.g.
  13. 'synpowerport on camb'
  15. CanopySync over Power Port is on
  16. CambiumSync over Power Port is on
  18. Telnet+> syncpowerport off
  19. CanopySync over Power Port is off
  21. Telnet+> synctimingport off
  22. Syncover Timing Port is off
  24. Telnet+> synconboard off
  25. On-boardSync is off
  27. Telnet+> synconboard on
  28. On-boardSync is on
  30. Telnet+>

Thanks for the replys, we have a few Rackinjectors at a some site's. They are much nicer to work with! Also thank you for the CLI, I didn't know that. We are currently running and 16.0.1