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nanoHD & false DFS Radar Events / Issues

[ Edited ]

First real issues I've had since deploying 10 nanoHD units in a school; Our HD deployment mean that using DFS channels would be ideal, but each AP (and once a neighboring AP) get false DFS Radar detection whenever there is serious WiFi activity on that AP. In other words, during any normal use it's all fine, but when we stick 25 laptops in a room for testing, that room's AP will mysteriously (and reliably) detect a radar event. Since this has been absolutely consistent, there is no way that these are actual radar events.

 

Additionally, the APs do not switch back to the preferred channel, even when leaving them overnight. Restarting them manually does reset to the proper channel.

 

Any suggestions (orther than submitting this as a bug report?)

 

Speaking of which, does ubiquity have a direct bug-report link I should be using?

 

Thanks!

 

UPDATE: Currently running firmware 4.0.21.9965 on all our Nanos and the next testing window just rolled around so I could see how things have progressed since the beginning of the school year. Today 3 testing sessions in 3 different parts of the building were launched, with up to 35 WiFi devices being woken from sleep or powered on essentially at the same time. In none of these cases did we get a false DFS Radar Event. So, knock on wood, it looks like this issue may be resolved.

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Re: nanoHD & false DFS Radar Events / Issues

Hello @waldengreen,

 

What firmware are you running on the UAPs?

What controller version are you running?

 

Whats the reason that you really need to use DFS channels?

 

 

Regards,

Glenn R.

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Re: nanoHD & false DFS Radar Events / Issues

[ Edited ]

Yes, I should remember to add those items each time:

 

Controller version 5.8.28

nanoHD firmware version: 3.9.45.9203

 

IHMO, my reason doesn't really come into it. It's a feature that is supposed to work a certain way, and therefore should work that way, regardless of my reasons for doing so. I think we tend to give the tech-industry way too many "passes" on this kind of thing. "Oh, that's feature is supposed to do this, but it doesn't really work so don't use it."

 

But since you asked: Non-traditional building design which adds considerable signal reflection and refraction issues, in addition to having all the usual penetration issues most traditional school buildings suffer. Being able to use DFS channels means I can easily deploy a 40hz 5ghz network without any overlap. Not being able to reliably use DFS channels will mean deploying a 20hz network on 5ghz. (The refraction/reflection issue means we sometimes get channel overlap / interference even from an AP on mimimum radio power at the other end of the building, on a different floor, which would, by line of sight, have to penetrate up to 5 solid concrete block walls plus a concrete floor between the 1st and 2nd story).

 

Thanks!

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Re: nanoHD & false DFS Radar Events / Issues

Hi Waldengreen,

 

I am just deploying NanoHD in our classrooms and so far not issues as you describe. I regulary have 30 - 50 clients on one AP. If you advise your firmware versions of controller and AP along with all channel settings I’ll try to reproduce your environment and test. 

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Re: nanoHD & false DFS Radar Events / Issues

[ Edited ]

@smart-thinking wrote:

I am just deploying NanoHD in our classrooms and so far not issues as you describe. I regulary have 30 - 50 clients on one AP. If you advise your firmware versions of controller and AP along with all channel settings I’ll try to reproduce your environment and test. 


Hi, thanks for the offer, it would be interesting to see if this is unique to some specific settings, but that's a lot of work on your end and my guess is that it's bugged code in the detection process. Here are the controller and firmware versions:

 

Controller version 5.8.28

nanoHD firmware version: 3.9.45.9203

 

All of the APs are currently on the "Medium" power setting.

 

Here is a screen-shot of what's happening - what you are looking at is a set of approx. 25-30 laptops being opened in a classroom for testing purposes (these are the events between 8:21 and 9:23 am). After that room tests, the laptops get carted to another room and the process is repeated (second testing session started between 10:31 and 10:48).

 

So far this has kicked-off a mystery "Radar detected" event nearly every time and in once case also caused an event on a neighboring AP. (Also, when picking a new channel, the nanoHDs have not done a good job picking a clear channel). I just don't see how it could be a coincidence; it's too consistent and I never see an even except during this high-usage scenario.

 

Screen Shot 2018-09-07 at 10.45.37 AM.png

 

Are there any other settings I should be looking at, or that you would want to see?

 

Thanks.

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Re: nanoHD & false DFS Radar Events / Issues

Hello @waldengreen,

 

For the giggles could you try 3.9.48?

 

 

Regards,

Glenn R.

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Re: nanoHD & false DFS Radar Events / Issues

I am on 3.9.48.9248 on my nanoHD (staying off 3.9.5x for now) and have the same DFS radar event issues.

 

For comparison, I have a UAP-AC-PRO in the next room which I have tested on the same channels + bw and it does not report radar detection (waited a day each time) - fw 3.9.50.9295.

 

Tested channels:

52 at VHT80

100 at VHT80

116 at VHT80

132 at VHT80

 

Regulatory domain: Singapore

 

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Re: nanoHD & false DFS Radar Events / Issues

hi @waldengreen , 

 

For FW (>= 3.9.50), we have fixe some issues for DFS false alarm, if you still encounter this issue (for FW >= 3.9.50), would you mind I PM you the temporary F/W to collect more information for analysis?

 

 

  Thanks

        Jeffrey

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Re: nanoHD & false DFS Radar Events / Issues

@waldengreen curious, are you need any kind of an airport? I was testing about a year ago near an airport (less than a mile away) and we were getting MASSIVE radar interference on 149–165 (U-NII-3). There were minor U-NII-1 pulses but I would certainly suggest removing DFS and manually configuring your channel use away from any U-NII-1 and 3. In the US, U-NII-2 was removed.

You m ay want to take a look at http://www.ieee802.org/18/Meeting_documents/2007_Nov/WFA-DFS-Best%20Practices.pdf and https://metis.fi/en/2017/08/dfs-en/ to get a better perspective. Also perform a site survey to be sure you are not getting hammered.
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Re: nanoHD & false DFS Radar Events / Issues

oh and I forgot to mention, many times the pulse has an SSID with the airport code and sometimes it's the type of pulse (purpose-based SSID). so you may want to scan for those as well.
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Re: nanoHD & false DFS Radar Events / Issues


@AmazedMender16 wrote:

Hello @waldengreen,

 

For the giggles could you try 3.9.48?

 

 

Regards,

Glenn R.


Yes, I will do so at some point. Unfortunately the school-year is already underway, so it will have to wait until I have time on a weekend to come in, perform the updates, and then walk the school testing things.

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Re: nanoHD & false DFS Radar Events / Issues

[ Edited ]

@UBNT-jeffreychang wrote:

hi @waldengreen , 

 

For FW (>= 3.9.50), we have fixe some issues for DFS false alarm, if you still encounter this issue (for FW >= 3.9.50), would you mind I PM you the temporary F/W to collect more information for analysis?

 



Will do so as soon as I can actually make it happen. I see people have already adopted the 3.9.48xxx firmware (was not a stable release candidate when I setup our nanos, so I used the latest stable release candidate available at the time). Will have to wait until a weekend is available in case it causes issues however.

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Re: nanoHD & false DFS Radar Events / Issues

Hi @UBNT-jeffreychang, I am encountering the same issues as OP on both FW ≥ 3.9.50 and 3.9.48.9248.

 

If you don’t mind, I would also like any test firmware that assists to debug/trace the DFS behavior of UAP-nanoHD. Thank you!

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Re: nanoHD & false DFS Radar Events / Issues

@andr3wyong 

 

I have  sent PM to you for the testing FW. 

 

 

 Thanks for your feedback and support 

 

     Jeffrey 

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Re: nanoHD & false DFS Radar Events / Issues

[ Edited ]

I was thinking of giving the 3.9.50.9295 version a go on a couple of APs this weekend, but now see that it specifically does not support the nanoHD. In general I'm not really in a good position to test possibly-unstable firmware releases during the school-year ("works OK" is way better than "doesn't work!") I'm currently running 3.9.45.9203. Is there a later *stable* release I should try?

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Re: nanoHD & false DFS Radar Events / Issues

Hello @waldengreen,

 

You could run 3.9.48.

 

 

Regards,

Glenn R.

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Re: nanoHD & false DFS Radar Events / Issues

[ Edited ]

@waldengreen 

 

 

Did you encounter any DFS false alarm ? We have fix and improvement for DFS false alarm and the FW is under testing. 

I can provide you a temp FW to test and  collect for information (if the AP is not occupied and availiable for testing)

 

 

Thanks for your feedback and support 

 

           Jeffrey  

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Re: nanoHD & false DFS Radar Events / Issues

[ Edited ]

@UBNT-jeffreychang,

 

May I be provided with the firmware for testing? I too get false alarms using the nanoHD. I live 2.5 miles from the Scottsdale airport. I know I get positive DFS pulse detections from there and from the Phoenix, AZ TDWR(5610 MHz) on the lower U-NII-2C bands.  These are detected by my AC-Pro and AC-LR as well.  The nanoHD will consistently detect radar in the U-NII-2A band when the others will not. Thanks.

 

 

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Re: nanoHD & false DFS Radar Events / Issues

hi  @superducphuc 

 

I have sent you the PM

 

 

    Thanks for your feedback and support

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Re: nanoHD & false DFS Radar Events / Issues

[ Edited ]

On Friday t installed a NanoHD in my home that has two existing UAP-AC-Pros and about 20 very standard WIFI devices. Today I had the DFS radar alert for the 2nd time in 3 days. FW ver 3.9.54.9373 on all APs. Nowhere near an airport or anything (rural suburbs surrounded by forest). RF scans are very clean. Not using DFS on the NanoHD. Neighbors over 100 feet away.

 

Here is today's NanoHD alert: "wireless event: DFS: Radar detected on channel 36 (freq 5180)."

 

The problem is after alert Nano switches to a higher channel close to one of the other APs And, at least when I came home from work today, 5 Ghz devices that were connected to that AP still showed as connected but had no Internet access until I restarted the NanoHD. I use static channels and transmit power.

 

For now I've just switched the NanoHD to a high channel and the nearest UAP-AC-Pro to low channel. Nano runs on high transmit power, the other APs medium.

 

The only interfence source I can think of is both of our Volvo's have ACC/safety radar (e.g. semi autonomous driving that uses video and radar) and in both occurances the NanoHD problems happened around the same time I pulled into the garage which is on the other side of the house from the Nano. But one of the stable UAP-AC-Pros is in the garage. That AP is using DFS channel 120 with no measurable signal reaching the room the NanoHD is mounted in.

 

Any ideas? I realize this thread is bit old but came up on my search.

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