AP550 Dual 5GHz Interference

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Deployed 80 AP550's over the summer in a public high school.  Building is three story with expansive first floor.  With HMOL, they are set up for dual 5GHz, with single-wide on wifi0 and double-wide on wifi1.  I am experiencing interference warnings on multiple APs spread out around the building.  But only on wifi1.  The interference coincides with arrival of students around 7 am, peaking in the mid 20% range and dropping off to under 3% after 4 pm.  I see no interference on nights or weekends.

I've attached screenshots of two APs that are in different parts of the building.  Looking at neighbor info, it does not appear to be co-channel.  I have walked the building with inSSIDer and found no hot spots that might cause it.  I am at a loss to explain it.  Any thoughts?

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boogins

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Posted 5 months ago

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Carsten Buchenau, Champ

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Hi,

With HMOL, they are set up for dual 5GHz, with single-wide on wifi0 and double-wide on wifi1.
Are you saying you are operating the same SSID with 20MHz wide channels on one half of the radios, and 40MHz wide channels on the other half?

That won't work, you will get roaming problems. And my guess is this is related to your interference messages.

Always run the same channel width on all radios in the same radio band. And in most cases this should be 20MHz, even for 5GHz.

You should also follow the dual-5Gig-channel-deployment-plan... a good start for reading is here:
https://boundless.aerohive.com/technology/Suffering-From-WiFi-Congestion-Dual-5GHz-Radios-Can-Help.h...

Hope this helps...
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boogins

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Thank you, Carsten.  That is exactly the kind of feedback I was hoping for.  I had read the article that you mentioned, but it didn't have this kind of advice.  I also look for some 'best practices' document for the SPR APs, but couldn't find one.

With both radios set to the same channel width, no more interference.  Thanks again.