Epmp 3000 dropping SM

Hi all, so what is the answer to the epmp 3000 dropping subscribers? I am running 4.4.3 because using any higher firmware release causes other issues worse than the AP dropping clients. I have 3 Epmp 3000 sectors on this tower, a north facing and a west facing and a east facing… all running 4.4.3 and the east and west are using frequency re use. The north facing sector does not have this issue at all, the east facing has one SM consistently being dropped and the west has 7 sm and they all get dropped randomly but all have been dropped, the shortest time they last before being dropped is a few minutes and the longest is around 2 hours.

I did try using 4.5.5 and 4.5.6 and customers had issues… before I switched to 4.5.5 the customers did not have any issues with AP dropping them and when I rolled the AP and customers back to 4.4.3 the issue of AP dropping the SMs remained.

I know many on the forum have experienced this. Please help as I have some unhappy customers. Thanks!


Could you please drop me the letter on fedor.trutsko(at)cambiumnetworks(dot)com?
I would be happy to address that issue out for you.
We are not aware of any disconnects issues on 4.5.6 firmware.
Any extra details would be highly appreciated(SMs models, Operational mode, Bandwidth, etc)

Thank you.

SMs are force 300 25 and 19, they are in bridge mode and clients bandwidth range from 20/4 mbps, 30/7 mbps and 40/10 mbps. There are 7 clients on the west sector and 10 on the east sector.

@Fedor Also did 4.5.6 fix bsa issues or does one still need to set to force sector antenna?

The majority of BSA related issue is addressed out in 4.5.4 and 4.5.6.
But the issue with inaccurate RSSI reporting when BSA is on is fixed in 4.6.

Thank you.

I am trying 4.5.6 and will monitor if any disconnects.
I also enabled ACS to see if maybe interference but the acs actually chose the frequency, 5240, that I was already using.

When is 4.6 full release happening?

@Fedor is it crucial that both firmware banks are updated? or is it fine to just update once and leave the inactive bank?

4.6 is coming in a few weeks.

Thank you… i am fine to go straight from 4.4.3 to 4.5.6 correct?

@Fedor So going on almost 2 hours with no SM dropping… but I think my issue is that the epmp 3000 is losing internet connectivity, I noticed while in the GUI of the radio the globe symbol went from green to grey to green in a half second or so… I need help diagnosing the issue… the ethernet status in the GUI of the epmp 3000 stays at 1000mbps full, never goes red.

@Fedor I had a SM get dropped by the AP so it is doing it even on 4.5.6, let me know what you need from me

Yes, you can go with the upgrade from 4.4.3 to 4.5.6 directly.

Ideally I would ask you for the remote access to your sector where the issue can be investigated.
But we can start with Tech Support Files collected from AP and at least 2 SMs which are experiencing disconnects.

Thank you.

@Fedor now I am also experiencing sm drops on the opposite sector (east) as well…this has just come out of nowhere, never experienced this before.

Had a similar problem. Not sure if you are using GPS sync. At the end of the day after installing external GPS antenna for the 3000’s, this was resolved.

Same here, no real responce from Cambium and definitely no garantee that it is identified and taken care of any time soon. Please advise of any other fixes other that going back to 4.4.3?

How do you know if GPS sync is not working? I have checked my system logs and see no GPS loss, on the web UI of the ePMP 3000 I have a green symbol, and I have satellites being tracked. Is this an actual GPS issue?

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I was going to mention this… Cambium makes it pretty easy to see if your GPS sync is working correctly in the form of the dashboard status indicator, log files, and tracked satellites page, etc. If these things looks positive, then GPS sync between correctly configured radios is GOOD TO GO!

IF you see GPS sync down and/or your settings are incorrect, then you’ll typically see the following issues:

  • In back to back frequency reuse situation, 1 or both AP’s will often start dropping some or all SM’s
  • Very poor modulation for SM’s
  • Frequent messages in the logs that GPS sync is lost and that free run mode is in play

Okay, well everything checks out: dashboard indicator is green, no synch errors in the logs, satellites are tracked.
I am experiencing your first 2 bullet points but just in the last few weeks, before that everything was A OK