AP showing "Jammed" and no logs are showing this activity

[valartemisa]

Hello Wireless Community,

i have encountered myself with an issue in a few of my organization networks where APs appear with "jammed" status from the Wireless>RF Spectrum section. it happens from maybe a few seconds randomly throughout the day and it affects all APs at some point. have you seen anything like this? The event log doesnt show these peak events and the channel/power doesnt seem to update properly when this happens.

MR52 is the AP model i am using.

Thank you!!

[PhilipDAth]

I have never seen anything like that.  Perhaps something else is clobbering the RF spectrum.

Does it happen in both the 2.4Ghz and 5Ghz spectrum?

[valartemisa]

I've seen it only on 2.4.. i could think is environmental, but it happens to random APs within the same network, which tells me is not the same area that is jammed. the weird thing is that the RF event log doesn't capture these RF peaks..

[PhilipDAth]

2.4Ghz interference is really common.  Look for things like DECT phones and close proximity to microwave ovens.  Bluetooth also uses the 2.4Ghz spectrum - so you can sometimes get loud or noisy bluetooth devices causing a problem.

[valartemisa]

would it be better that 2.4 radios get turned off?

[PhilipDAth]

I disable 2.4Ghz on just about all customer "corporate" networks.  If you don't need it - disable it.

[valartemisa]

the environment is retail, so you can imagine how crowded it can get. i am mainly worried for guest clients that are not 5 Gig capable

[PhilipDAth]

If it is for guest WiFi you'll need to leave 2.4Ghz enabled.

[valartemisa]

yes, that is what i thought. i am broadcasting my corp in 5 Gig only though.. i will keep monitoring the site, but i wish the even log within the AP's RF section displayed this behavior and generated an alert somehow.

[Ryan-Zimmerle]

In an environment where I have many APs where I have planned for density, many times I will only broadcast 2.4 on a handful of the radios to make use of the limited channel availability and RF considerations.  It sounds like you need to leave 2.4 enabled, in that case do you need 2.4 enabled on every AP?  Also, are you band steering clients over the 5 GHz, I would enable that if you have not already.  

[Thelmo]

Jammed Channel

The dashboard detects a jammed channel by analyzing utilization. If the non-802.11 utilization on one of the client-serving radios is 65% or greater for 1 min, the dashboard will instruct the AP to change to a different channel. The utilization that is analyzed is non-802.11 interference that would be transmitted by a microwave or wireless video camera.

Clients that are on the AP during the channel switch will be instructed to move with the AP to a new channel via a channel switch announcement (CSA) which will maintain their connection. Clients that do not hear the CSA over the interference will re-associate with an AP (either the original AP or roam to another one).

Reference 

 https://documentation.meraki.com/MR/Monitoring_and_Reporting/Location_Analytics/Meraki_Auto_RF%3A__W...

[claudiob]

one question :

in RF live, you see 802.11 Traffic and non-802.11 Interference in what percentage?

how many SSID do you have on access point?