Reply
Highlighted
Regular Member
Posts: 303
Registered: ‎09-26-2010
Kudos: 88
Solutions: 4

False DFS events in AirControl

Running 2.1-GA3 and 8.5.1 on the AP.

 

Doing a site survey while clients are connected will cause AirControl to report a DFS event has happened. 

Veteran Member
Posts: 4,462
Registered: ‎03-02-2015
Kudos: 855
Solutions: 199

Re: False DFS events in AirControl

@supers

Can you reproduce it or just coincidence with sitesurvey?
I guess nothing of DFS in device logs?
Can you attach dashboard of AP and response of 'mca-status' via ssh ?
===================================================
We all work for KUDOs here.
Thx
Regular Member
Posts: 303
Registered: ‎09-26-2010
Kudos: 88
Solutions: 4

Re: False DFS events in AirControl

I can reproduce it by issuing the site survey again.

 

The AP in question is running on 5810 so DFS isn't really possible. Nothing appears in the aircontrol debug logs for the time frame. Nothing in the AP logs either.

 

mca-status output:

 

deviceName=TowerAP,deviceId=80:2A:A8:A4:47:6D,firmwareVersion=XC.qca955x.v8.5.1.37185.180307.0931,platform=Rocket 5AC Prism,deviceIp=192.168.75.19

apMac=80:2A:A8:A4:47:6D
wlanOpmode=ap-ptmp-ac
wlanConnections=10
wlanUptime=10968
essid=removed
security=WPA2
freq=5810
centerFreq=5810
txPower=27
chanbw=20
signal=-62
chain0Signal=-65
chain1Signal=-68
noise=-81
cinr=25
evm=24
uptime=276259
airTime=9.6
cpuUsage=9.9
loadavg=0
memTotal=126928
memFree=82600
memBuffers=3820
distance=8100
netrole=bridge
lanIpAddress=0.0.0.0
wlanIpAddress=0.0.0.0
wlanTxRate=117.9
wlanRxRate=107.5
txModRate=6x
rxModRate=6x
wlanTxLatency=7
wlanPolling=1
wlanDownlinkCapacity=68276
wlanUplinkCapacity=27456
lanRxBytes=9047304317
lanRxPackets=107925744
lanRxErrors=0
lanTxBytes=3942821226
lanTxPackets=56356425
lanTxErrors=0
lanPlugged=1
lanSpeed=1000Mbps-Full
cableLen=24
wlanRxBytes=356780429
wlanRxPackets=2328118
wlanRxErrors=0
wlanTxBytes=7313629883
wlanTxPackets=5221856
wlanTxErrors=0
wlanRxErrNwid=188
wlanRxErrCrypt=0
wlanRxErrFrag=0
wlanRxErrRetries=0
wlanRxErrBmiss=0
wlanRxErrOther=0
latitude=
longitude=
boardCrc=fba916ab
cfgCrc=b3e36388
status_flags=4

Dash Board:

 

 

dashboard.jpg
Regular Member
Posts: 303
Registered: ‎09-26-2010
Kudos: 88
Solutions: 4

Re: False DFS events in AirControl

[ Edited ]

Screen shot from AirControl

 

 

 

aircontrol dfs.jpg

Veteran Member
Posts: 4,462
Registered: ‎03-02-2015
Kudos: 855
Solutions: 199

Re: False DFS events in AirControl

@supers

Thanks for info.

@UBNT-Karolis
===================================================
We all work for KUDOs here.
Thx
Ubiquiti Employee
Posts: 711
Registered: ‎05-28-2012
Kudos: 361
Solutions: 76

Re: False DFS events in AirControl

Hi @supers,

 

can you check Events tab for this DFS event and see what was actual frequency change (there should be details with from => to frequency)?

Ubiquiti Employee
Posts: 711
Registered: ‎05-28-2012
Kudos: 361
Solutions: 76

Re: False DFS events in AirControl

@supers nevermind. I can confirm that the issue exists. The problem is that during Site Survey device temporarily changes frequencies and they get reported with heart-beat. Our DFS change detection is based on frequency change and we get a false positive. So for now you should simply ignore these events created during Site Survey. There is no simple solution for this and we might not resolve this issue for v2.1

Regular Member
Posts: 598
Registered: ‎03-11-2013
Kudos: 267
Solutions: 12

Re: False DFS events in AirControl

[ Edited ]

I'm experiencing a related problem in AC2 v2.1-GA.  See here: https://community.ubnt.com/t5/airMAX-Wireless-Networking/False-DFS-Event-Warning/m-p/2324725#M62184  Given the info in this thread, I'm going to surmise that my first report was related to running AirView.

 

I think I just figured out the second report: https://community.ubnt.com/t5/airMAX-Wireless-Networking/False-DFS-Event-Warning/m-p/2331381#M62221  In that second report, it was 4:00 in the morning.  No one was running AirView or Site Surveys on that AP.  It just dawned on me that the radio's logs are off an hour since the AirMAX firmware doesn't respect Daylight Savings Time.  Given this revelation, the DFS event is explained by the AP having it's frequency set to Auto.  We have an Automation Rule that reboots radios automatically every 7 days at 4:00 in the morning.  The AP was rebooted by the Automation Rule, but since the CPE feeding it was rebooted at the same time, the reboot was masked as an offline & online event.  When the AP came up, it ran it's own Site Survey to choose a channel, resulting in the false DFS event.

Dreams never hurt. It's when they turn into expectations that you get problems.
Veteran Member
Posts: 4,462
Registered: ‎03-02-2015
Kudos: 855
Solutions: 199

Re: False DFS events in AirControl

@RavenWing71

I've seen that couple of months ago with watchdog related reboot and Frequency list which chooses sometimes a different frequency and reports false DFS event.
Expected behavior and nothing to worry.
===================================================
We all work for KUDOs here.
Thx
Reply