Aironet 3802i cleanair down when using 160mhz channels (Mobility Express)

[sramgolam]

Hello Everyone,

I have a single 3802i with Mobility Express 8.5.131.0 running and whenever I set the 5ghz channel to 160mhz the cleanair status for that radio goes to admin enabled but status down. I've tried this on 8.7 with the same problem. Cleanair works when bandwidth is 20, 40, or 80. But not 160.

To reproduce the problem you can do this:

• Start with fresh ME install
• Set radio 0 to 2.4ghz only
• Set radio 1 to 5ghz only
• Create two wpa2 wlans and set one to 2.4ghz and the other to 5ghz
• Change the channel bandwidth in RF Optimization expert settings to 160mhz (Make sure cleanair is enabled)

I saw the bug below which describes my problem but its related to the 5500 WLC series.

CSCvk63452

Any help would be appreciated.

[Rasika Nayanajith]

Yes, that could be the issue.

By the way, do you really require to use 160MHz ? Is it practical ?

Rasika

[sramgolam]

There aren't many devices that support 160mhz as yet but for my purposes it is practical. The product specs state that cleanair should work on the 160mhz band so i'm trying to determine why its not working.

[Rasika Nayanajith]

With the amount of channel available today, you cannot have more than 1AP in your environment if you use 160MHz (in UNII-1, 2 & 3 bands). So it will be the limiting factor of 160MHz deployment. 

Below from a Ciscolive presentation that summarized frequency availability in 5GHz

HTH

Rasika

[sramgolam]

I currently have 2 160mhz channels to choose from. Either way I only need 1 right now. I'm not worried about overlap. That's not the issue at hand. I think practicality is for another discussion.

[pieterh]

maybe your interpretation of the datasheet is a little optimistic about  160MHz

I did not find any confirmation, but I think you need to read it as such:

- the AP supports 160MHz channels

- cleanair supports 160MHz channels

but that does not necesarily mean it supports both at the same time!

if you happen to have two AP's available, configure one AP in monitor-only mode and the other as normal AP.

[sramgolam]

I don't see a way to configure the second radio as monitor mode in Mobility Express i don't think that is supported. If i configure the first radio as 160mhz cleanair works fine.

[pieterh]

according to this deployment guide

Primary 5GHz radio can service clients, while the secondary 5–GHz radio can be used to  enable testing of wider 160MHz and/or newer channels as they become available – allowing  new features without limited performance

so as of  WirelessLANController(WLC)AirOSrelease8.2MR1

the access point as device should not me the limiting factor to serve clients and monitor rf spectrum at the same time!