why would Aerohive use only 2 channels on 4 APs in a 3-ch model?

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We are using the channels model: Europe, 3-channel, 1-6-11 and I now notice that Aerohive has picked only 2 channels for 4 AP141's placed in the same production-hall.

The 2 on the left are on ch 11, while the 2 on the right are on ch 6. It is not clear why it would not pick ch1 on at least 1 AP. Because of the remote location, there is hardly any interference from neighboring wifi.

Why is this? Is there a scenario were they would rather use the same channel?
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Jornt Weyts

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Posted 5 years ago

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Brian Powers, Champ

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It shouldnt be a scenario where they'd rather use the same channel as all the clients on the 2 APs on the same channel are sharing the same frequency space and are all contending for transmission time.

Issuing a show acsp neighbor command from the CLI of the APs will show you the neighbors that it sees and maybe they saw an AP on channel 1 (someones hotspot for instance) at boot up (the time that it decided which channel to choose) and opted for the channels that it did choose.

It'd be a nice feature if there'd be some way to redo the channel selection process (ala Cisco RRM) without rebooting the APs as that was the fix I was told way back when I asked my local SE a similar question
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Andrew MacTaggart, Champ

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Radio policy - auto channel switching - select the times and what will initiate a channel switch.

consider reloading the APs at different times, in case they listen to the air and determine channel is good at the same time.

but often, if APs assess the air they might determine that co-channel interference is better then what the environment offers. depends on the environment and depends on the APs

I would lower the power for the APs and see if they choose different channels

dfs channels have to switch within 10 seconds on detecting Radar.

If you know the RF environment you can set the channels and power for each AP and monitor for interference. A remote loco with no Interference would be ideal for static settings.

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Brian Powers, Champ

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Thanks Andrew. I never noticed that feature there. Any idea when it got added? The help file also states you can disable and re-enable the feature the AP will scan for new channels to use.

Channel Auto Selection: Use this option for radio profiles that you intend to use in access mode with automatic channel selection enabled (see "Aerohive AP Settings"). This option allows you to set the conditions when an AP automatically scans the transmission medium for a better—that is, less busy and less noisy—channel. If it finds one, it then switches to that channel. By default, this option is disabled and an AP radio automatically chooses a channel only when it first boots up (and also if you disable and re-enable the automatic channel selection feature). If you enable this option, the AP radio also does a channel selection scan during the time period that you set and only if the number of clients currently using the radio are equal to or fewer than the maximum. During this time, the AP re-evaluates the channel that is currently in use and might switch to a different channel or continue using the same one.
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Andrew MacTaggart, Champ

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Hi Brian

I am not sure when this feature was added, but I know it was in 6.1r1.

I read about it in the High Density and Configuration guide.

The most interesting thing is that it considers historical data

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Amanda

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Good find Andrew! Thanks for figuring it out and posting.