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802.11 a/n radio flapping on Cisco 1522 AP >>>%DOT11-6-DFS_TRIGGERED <<<



I have a wireless network with 4 1552 out door AP. All are RAP and connected to the network.2 of the AP a/n radio is going flapping continously... When I connected AP console, I got the below error
: %DOT11-6-DFS_TRIGGERED: DFS: triggered on frequency 5805 MHz
:adj_Maint: received go quiet indication.
:adj_Maint: Ignoring go quiet, this is a RAP.
: %LINK-5-CHANGED: Interface Dot11Radio1, changed state to administratively down
: %LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio1, changed state to down
This appears when When radar is detected on a channel ..
My WLC code is 7.4
How we can fix this sissue ?? Thanking everyone in advance
Hall of Fame Super Silver

DFS which is to detect radar

DFS which is to detect radar and go off channel is implemented in uni-2 channels.... What you can do is only use uni-1 or uni-3 channels which you would define in your RAP.

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Community Member

 Dear Scot, Thanks a lot for


Dear Scot,


Thanks a lot for yourresponse

Thease are the channels enabled on DCA channel list 36,40,44,48,52,56,60,64.


But I can see the APs connected with channel161,100,104..I tried to delete this channels and WLC couldnt find the channel list.

How we can enable use uni-1 or uni-3 channels in WLC..Unii 2 channels are already disabled


Waiting for your reply

Thanks and Regards


VIP Purple

HI ,Agree with scott: you

HI ,

Agree with scott: you must select UNI-1 and uni-3 channels if any kind of radar detected.

On the 5ghz you are restricted with channels that exist with radar.  You can disable the DFS channels so that AP's don't use these

How to disable :

1. you can try statically assigning channels for those APs.

2. Normally  DCA globally set to freeze. set it to auto and then went into each AP that was on a UNI2 channel and set it to custom, then save it.

3.Try to disable the A/N network.  Make sure the 52-64 aren't in the list, and then reenable the A/N network.

Hope it helps.



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Community Member

Dear Sandeep,Thanks a lot for

Dear Sandeep,

Thanks a lot for your advice..I have reconfigured the channel list for 802.11 a/n

This is my current DCA channel list

The channels in UNII-1  36, 40, 44, 48,

The channels in UNII-3 149, 153, 157, 161


I will monitor it and update you the status ASAP





Community Member

Dear Sandeep, Still the issue

Dear Sandeep,


Still the issue is not solved..I am facing the same on one of the AP..

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