Does GPS Sync rely on some central server?

I have 4 different towers, all in the same general area. They each have 4x PMP 450i/m APs on them. They aren't even all the same, some are 3GHz, some are 5GHz.

They all lost GPS sync at the same moment, now they are getting/losing GPS sync over and over.

I'm trying to determine, is there some kind of localized GPS failure? Or do these all somehow rely on some Cambium service that is failing?

I think this is more widespread, we are experincing this on many towers

I am only seeing this on my CMM5's currently. Can you tell me what CMM you are using?

We are in southwestern ontario and we had the same on most of our medusas. Some are CMM5 and some with a uGPS. It happened at exactly 4pm est.

All of mine are uGPS, 2 APs to a GPS unit. Happened at exactly 2PM mountain time.

West coast and had this happen about 1pm, but only on my 450i's getting sync from auxillary port. My CMM mountaintops were not affected. I rebooted every single site and they seem to be holding steady.

uGPS is the GPS unit that provides sync to the CMM5 units. so that would make sense.

We have clients in Minnesota and Iowa - also having this issue, on CMM5 with uGPS.

Appears that we're losing sync to the CMM5 itself, intermittently.

CMM5 controller 4.4.14 --  Chassis FW 00.13 in all cases so far.

Having trouble in south Louisiana also.  Only the site's which use uGPS antennas are not seeing sync.  Just got off the phone with Cambium support, and the rep confirmed a satelite problem.  ETA 2 hours to repair.

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Thanks for the update from Cambium. My network has stablized, but I'm going to hope that two hour ETR won't rear its head. I'm ready for the day to be done!

No problem.  It's weird that the sites that use Master GPS modules aren't experiencing this.  I guess those use a different bird.

Happened to me I lost some 6 sites some are 200+ miles of seperation. 

For us it wasn't any site with a CMM, it was all of our sites using GPS through the aux port. Made it much easier to cut power to the GPS unit then with the CMM.

Evening everyone.

We are currently looking into the possible cause of the GPS interference/outage we are seeing with GPS sync, currently there seems to be a GPS interferer or outage affecting the uGPS receivers and PMP450 APs with integrated GPS.

The GPS sync does not rely on a central server for timing as it synchronizes its internal clock with the GPS units in orbit.

Correction on Firmware versions on CMM5 --

CMM firmware versions 1.3 and 1.4 are not working... thought we do have one CMM5 with a uGPS that *is* working so far.

Hello, do you have a link to any information on this issue? We have 60+ units that are seeing major issues right now. 

From Cambium:

Thank you for contacting Cambium Networks.

I understand that you are experiencing an issue with PMP450 APs which

are loosing GPS sync.

There is some issue going on with the satellite in USA or may be a bad

whether condition due to which we are getting many complaints from

multiple customers since last one hour for same issue.

There is no issue with our ePMP or PMP radios; however, you can

configure the PMP450 AP with "Auto Sync+ Free run" as a temporary

workaround and increase the Sync hold off timer on ePMP radios based

on the time it losses sync

We are trying to find out the cause of the issue and keep you posted

in 24-48 hours.

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We have the same problem in Oppdal - Norway.

None of our CMM5 sees any satellites, but CMM4 seems to work as normal.

We have the same problem at all of our CMM sites

Webber same problem in south Florida

We have the same problem in south Florida