I am still new to ePMP, but I have a potential issue. I upgraded a client from AirmaxAC to ePMP 4625 yesterday. The client gets the RX signal that Linkplanner said it should get (-63), but the DL rates on the client are unstable. By % they are mostly getting MCS 9, but they have issues where the RX rate will drop to DS 5 and even SS 11 with no visible change in signal.
This was the 12th client added to this AP.
Based on their shot to the tower I assume some of this could be multi-path or reflections from the pole barns on their property. I am on 6ghz rural and there is no noise I could find.
Beyond figuring out their connection it seems since I brought them online that other clients on the AP are now having RX rate instability, they did not have prior.
Can this SM be causing this? This SM is near one edge of the AP beam, but a client that seems to be unstable since adding this SM is on the opposite edge.
Since SM1 is on the beam edge it can see the East AP (only 2 clients) at about the same signal. As a test I am moving it to the other AP to see if that improves the rates for the SMs on the South AP (11 clients) and if this SM now causes rate issues for the East AP.
These are all 5.9.2. I was waiting until 5.10 final as I do not need MU-MIMO at the moment, but if you think 5.10 has a fix for this issue I can try it. It will have to be sometime next week as we have good storm rolling through this weekend.
I will also mention that since moving SM1 to another AP that SM2 and all the other SMs RX rates are back to their normal stable rates. Also SM1 on the other AP, while the rates are lower due to lower signal, is also more stable.
I’ll provide charts later to show the change after some more time has passed.
Here are photos showing the improvements after moving SM1 from its preferred AP to the adjacent AP. SM1 lost around 2-4db in signal and has lower peak rates but they are much more stable.
Very odd. Almost makes me think some type of timing or scaling issue with the AP scheduler. I will try to report back next week once I have had a chance to try 5.10RC33 and move SM1 back to its preferred AP.
I just had the same thing happen to another AP today after installing a new SM. This other AP is over 6 miles away from the AP in the OP.
Like the AP in the OP it was after I added the 12th client. As soon as that client was added the RX rates of the other 11 clients went from stable to unstable.
So for me I now have 2 APs on different towers whose SM RX link rates became unstable after adding a 12th client.
Did you open the ticket with Cambium Support?
We would ask you to send Tech Support Files collected for every issue reported.
That will give us the information needed to help you out.
yes I have an existing ticket for the previous AP that experienced this issue but when I opened the ticket I didn’t make the correlation about the number of SMs connected to the AP being the possible trigger and thought it was a one off issue.
Now with it happening under the same conditions to another AP on another tower it seems like a bigger issue.
I just today updated that ticket with this new information I found from this AP today since they were both doing the same thing I went ahead and just added that information to the existing ticket.
I upgraded the most recent AP from 5.9.2 to 5.10rc35 and the SMs. I then moved the new SM back to its preferred AP, making it the 12th client again, and so far the recent beta seems to have fixed the 12th SM issue.
Issue when adding 12th SM on 5.9.2 (Yellow SM added/Red SM removed)
However, I am still having issues with SM UL rate stability after upgrading to 5.10rc35 as mentioned here. So the recent beta looks to have fixed one issue but caused another.
