Radio Profile - channel selection auto - neighbor APs on same channel & running at Max power allowed.

[w1f1n00b]

I’ve been seeing many instances where APs are on the same channel as their neighboring AP with RSSI in the 60s or 70s. I’m looking for steps to take to prevent this that don’t require manual channel plans, as I have too many APs to manage in that manner (wish this wasn’t the case).

In this one example I’m trying to figure out why the two radios are showing drastically different channel costs. full disclosure, not really sure what these numbers mean or how they’re calculated so any info or resources are greatly appreciated.

Also of note, these Radio Profiles are set to auto power selection with max power of 14dB. There are 50+ APs at the site (apx every other room), yet every AP is running at power 14. none have adjusted power down at all. Is this typical? My understanding is that even if Co-channel and adjacent channel interference are minimized, RF should still be kept to minimum power necessary to avoid general interference.

[KevinP1]

@john_kern I feel your pain. I had to turn off the dual 5GHz radios because of similar issues on the AP650. I know, it’s 2020 and we’re still being led to use 2.4GHz because of these situations.

However, I am using DFS and have ACSP enabled as well. Power on the 2.4GHz radio is 1 dBm and the 5GHz radios are at 2 dBm w/ band steering enabled. The only exceptions are in larger areas (gyms, cafetoriums, libraries, etc.) These areas may have dual 5GHz enabled along with automatic power adjustment.

With AP’s in every classroom, using the automatic power adjustment isn’t nearly as effective as it should. You should be able to fine-tune your auto power levels however you see fit; not min 2 dBm and max starting at 10 dBm. Like what you are seeing, radios using the same channel right next to each other, yet they won’t change the channel. However, DCS works well for us in the evenings but really didn’t help with the dual 5GHz radios from using the same channels. I would still find high CCI, CRC, and duplicate channels next to each other. Hence, needing to turn on the 2.4GHz band  and the intended by design limitations with turning a radio off  .

As for MU-MIMO, I haven’t had one GTAC engineer recommend enabling it .  I really want to use it, along with so many other important features with ours AP’s, but enabling certain features and perameters have broken user connectivity one too many times.

@daniel.schickmair thank you for sharing that link; I hope it does correct the issue.

[daniel1]

You can decrease this value to 16dBm in your Radio Profile, no client can take advantage of 20dBm.

[jose_gonzalez]

@john_kern In your heatmap screenshot you have 10 APs, if both radios are in 5ghz that’s 20 channels.  Looking at your ACSP channel cost screenshot you have 4 channels on the low side of the 5ghz band and 5 on the high side, for a total of 9.  So for that small area you have 9 available channels for 20 broadcasts.  ACSP is doing a bad job because there is so much overlap.  Enable DFS and ACSP will do a better job.

[w1f1n00b]

Here’s another example I just came across where it appears ACSP is struggling. I find it interesting that only the APs on ch36 have adjusted radio power down, while all other radios are running at max allowed power (20dB in this case). I will admit, this device template needs tweaking as it’s meant for lower density deployments, and this site has a higher than typical number of APs, but it does provide a good example of what appear to be the current limitations or deficiencies with ACSP. ACSP Neighbor CLI is from AP in 03-005

[daniel1]

I’m periodically checking the Extreme Portal for new articles for our AP650 (because as you know, known issues in the release notes are not reliable (yet) ).

Just input in your case “AP250” or your current firmware version “10.0r9a” (with double quotes) in the search field, filter Knowledge as source on the left and sort after date.