ePMP Interference

I am having problems with AP's being interfering with SMs on the AP 180 out and synced.  I am seeing this issue on multiple APs.  All my APs are on 3.5.1 with the the most recent GPS firmware, with plenty of channel seperation.  The only thing I can think of is that the SM's are close to the site less than 2 miles.  

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What do you have your AP's Subscriber Module Target Receive Level set to? This should typically be no stronger then 60dBm. Make sure you have all of your SM's Max TX Power set to Auto.

What makes you think that your SM's are interfering with your AP's?

All SM's are set to auto, and the AP's recieve level is set to -60.  The reason I am thinking the SM's are interfering is because they keep coming up on the eDetect (if thats how it works?).  

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eDetect shows you signals seen on the exact same channel as the device running the scan.  Are you saying that you see all the SMs from another AP, or the AP they're registered to, or what?  If they're on the same channel but a different AP (call it AP2) and you can see them from the first AP (AP1) then you will have trouble.  If they're clients on the AP running the scan then there should be no problem whatsoever. (though if everything is working correctly, I don't think they should ever show up on the AP they're actually registered to)  If you tick "AP/SMs" instead of "AP" when running eDetect, it will run on all clients of that sector plus the AP, simultaneously, and the report will include all the clients and indicate any interfering signal seen by each.

j

I am seeing SM's from AP1 that is synced with AP2 on AP2's edetect.  This is a fairly common issue that i am seeing on this site with all of my AP's.  I only run the edetect in AP mode.

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Interesting issue, Following

Image result for eating popcorn gif


@sherwoodj28 wrote:

I am seeing SM's from AP1 that is synced with AP2 on AP2's edetect.  This is a fairly common issue that i am seeing on this site with all of my AP's.  I only run the edetect in AP mode.


Are you using back to back frequency reuse on AP1 and AP2 (same channel & channel width)?

What antennas are you using on these AP's?


@sherwoodj28 wrote:

I am seeing SM's from AP1 that is synced with AP2 on AP2's edetect.  This is a fairly common issue that i am seeing on this site with all of my AP's.  I only run the edetect in AP mode.


So are AP1 and AP2 on the same frequency?  And the same tower?  If so, to make that work reliably (with Cambium sector antennas) you'll need them basically 180 degrees apart (back to back), and you set Frequency Reuse to 'Front' for one and 'Back' for the other.  

If they are adjacent (or worse still, overlapping) APs on the same tower (we usually number from AP1 to AP4 for North, East, South, West, then 5-8 for overlays) then they can't be on the same or overlapping frequencies or they WILL interfere with each other.  You won't observe much trouble until both APs have moderate levels of traffic on them at the same time, but it will still be happening.  Less than 180 degrees apart may work, depending on the antennas in use - there are some horn sector antennas available, for example, that offer 30 degree wide sectors, where two sectors 90 degrees apart are unlikely to interfere - but with standard 90-120 degree sector antennas, reuse is only stable if they're back-to-back.

If they are on separate towers then you need to revisit your frequency plan, and try to ensure that no AP will readily see clients of another AP on the same channel, and that no SM will readily see two or more APs on the same channel, unless there's a significant difference in signal strength.  Not always possible, but do the best you can to give you the cleanest starting point.  (General rule -with working sync at both, two APs aiming straight at each other can share a channel, two aiming the same direction from two towers usually canNOT since they will both probably be visible to many SMs and at least one will probably see the other's SMs, and therefore interfere)

If you're seeing AP1's clients from AP2, but they're all really weak (like 20dB+ weaker than AP2's clients) then you should be workable.

j

I'm not seeing anywhere in your posts what problems you are experiencing. Can you explain the actual problem, besides SM's showing up in edetect ( this will happen even in a properly configured network)? Low throughput, SM's disconnecting, high retransmission, etc? Hard to help with no actual symptoms. 

Edit: this is addition to other replies. 

The AP's in question are 2000s w/ cambium antennas and beamforming antennas, they are on the same channel 180deg out and gps synced (one front and one back).  Customers complaining of reduced speeds at peak times and I am not seeing peaking traffic nor CPU in maestro or SNMP.