Log message: user.warn kernel: NF Channel measured

[jason_reich]

We have several ZF7782 APs (running 9.10.2.0.63 with ZoneDirector) and I'm looking at the syslogs, and there are many kernel "user.warn" messages about NF Channel measurements.  They sometimes come (in threes) once a second, then skip several seconds, then a couple more, etc.  See below for a snippet.

The fact that they are warning level concerns me, but I have no idea what they are trying to say.  Can anyone help explain them?

And while I"m asking, what are the "user.info" messages with four hex values?

thanks in advance for any help you can provide
Jason Reich.

May 12 06:12:45 SW CH user.warn kernel: NF Channel 5765 Chain 0  measured latest ctl:-105 ext:-103  capped median ctl:-105 ext:-103
May 12 06:12:45 SW CH user.warn kernel: NF Channel 5765 Chain 1  measured latest ctl:-109 ext:-108  capped median ctl:-109 ext:-108
May 12 06:12:45 SW CH user.warn kernel: NF Channel 5765 Chain 2  measured latest ctl:-106 ext:-106  capped median ctl:-106 ext:-106
May 12 06:12:45 SW CH user.warn kernel: wifi1: 3774792546 : stuck beacon (missed 3) scanning 0, syncbeacon 0, sc_beacons 1,sc_isCaldone: 1
May 12 06:12:45 SW CH user.info kernel: 0x5a 0x46  0x37  0x37
May 12 06:12:46 SW CH user.warn kernel: NF Channel 5765 Chain 0  measured latest ctl:-105 ext:-103  capped median ctl:-105 ext:-103
May 12 06:12:46 SW CH user.warn kernel: NF Channel 5765 Chain 1  measured latest ctl:-109 ext:-108  capped median ctl:-109 ext:-109
May 12 06:12:46 SW CH user.warn kernel: NF Channel 5765 Chain 2  measured latest ctl:-106 ext:-106  capped median ctl:-106 ext:-106
May 12 06:12:46 SW CH user.warn kernel: wifi1: 3774793706 : stuck beacon (missed 3) scanning 0, syncbeacon 0, sc_beacons 1,sc_isCaldone: 1
May 12 06:12:46 SW CH user.info kernel: 0x5a 0x46  0x37  0x37
May 12 06:12:47 SW CH user.warn kernel: NF Channel 5765 Chain 0  measured latest ctl:-104 ext:-103  capped median ctl:-105 ext:-103
May 12 06:12:47 SW CH user.warn kernel: NF Channel 5765 Chain 1  measured latest ctl:-109 ext:-109  capped median ctl:-109 ext:-109
May 12 06:12:47 SW CH user.warn kernel: NF Channel 5765 Chain 2  measured latest ctl:-106 ext:-105  capped median ctl:-106 ext:-106
May 12 06:12:47 SW CH user.warn kernel: wifi1: 3774794763 : stuck beacon (missed 3) scanning 0, syncbeacon 0, sc_beacons 1,sc_isCaldone: 1
May 12 06:12:47 SW CH user.info kernel: 0x5a 0x46  0x37  0x37
May 12 06:12:48 SW CH user.info kernel: 0x5a 0x46  0x37  0x37
May 12 06:12:48 SW CH user.info kernel: 0x5a 0x46  0x37  0x37
May 12 06:12:49 SW CH user.info kernel: 0x5a 0x46  0x37  0x37
May 12 06:12:49 SW CH user.warn kernel: ath_get_radio_stats:Add counters, tx_errors=5877679 rx_errors=327847 tx_dropped=0 rx_dropped=0
May 12 06:12:49 SW CH user.warn kernel: ath_get_radio_stats:Add counters, tx_errors=2028622 rx_errors=582702 tx_dropped=0 rx_dropped=8
May 12 06:12:49 SW CH user.info kernel: 0x5a 0x46  0x37  0x37
May 12 06:13:07 SW CH user.warn kernel: NF Channel 5765 Chain 0  measured latest ctl:-105 ext:-103  capped median ctl:-105 ext:-103
May 12 06:13:07 SW CH user.warn kernel: NF Channel 5765 Chain 1  measured latest ctl:-109 ext:-108  capped median ctl:-109 ext:-109
May 12 06:13:07 SW CH user.warn kernel: NF Channel 5765 Chain 2  measured latest ctl:-107 ext:-106  capped median ctl:-106 ext:-106
May 12 06:13:07 SW CH user.warn kernel: wifi1: 3774814968 : stuck beacon (missed 3) scanning 0, syncbeacon 0, sc_beacons 1,sc_isCaldone: 1
May 12 06:13:07 SW CH user.info kernel: 0x5a 0x46  0x37  0x37
May 12 06:13:17 SW CH user.warn kernel: NF Channel 5765 Chain 0  measured latest ctl:-105 ext:-104  capped median ctl:-105 ext:-103
May 12 06:13:17 SW CH user.warn kernel: NF Channel 5765 Chain 1  measured latest ctl:-109 ext:-108  capped median ctl:-109 ext:-109
May 12 06:13:17 SW CH user.warn kernel: NF Channel 5765 Chain 2  measured latest ctl:-106 ext:-105  capped median ctl:-106 ext:-106
May 12 06:13:17 SW CH user.warn kernel: wifi1: 3774825139 : stuck beacon (missed 3) scanning 0, syncbeacon 0, sc_beacons 1,sc_isCaldone: 1
May 12 06:13:17 SW CH user.info kernel: 0x5a 0x46  0x37  0x37
May 12 06:13:18 SW CH user.warn kernel: ath_get_radio_stats:Add counters, tx_errors=5877705 rx_errors=327848 tx_dropped=0 rx_dropped=0
May 12 06:13:18 SW CH user.warn kernel: ath_get_radio_stats:Add counters, tx_errors=2028625 rx_errors=582703 tx_dropped=0 rx_dropped=8
May 12 06:13:19 SW CH user.info kernel: 0x5a 0x46  0x37  0x37
May 12 06:13:19 SW CH user.info kernel: 0x5a 0x46  0x37  0x37
May 12 06:13:19 SW CH user.info kernel: 0x5a 0x46  0x37  0x37
May 12 06:13:19 SW CH user.info kernel: 0x5a 0x46  0x37  0x37
May 12 06:13:20 SW CH user.warn kernel: findchannel:925 Found matching channel for chan(52) chanflag 0x11100 flags(0X10100)
May 12 06:13:20 SW CH user.info kernel: 0x5a 0x46  0x37  0x37
May 12 06:13:30 SW CH user.info kernel: 0x5a 0x46  0x37  0x37
May 12 06:13:35 SW CH user.warn kernel: NF Channel 5765 Chain 0  measured latest ctl:-105 ext:-103  capped median ctl:-105 ext:-103
May 12 06:13:35 SW CH user.warn kernel: NF Channel 5765 Chain 1  measured latest ctl:-109 ext:-108  capped median ctl:-109 ext:-109
May 12 06:13:35 SW CH user.warn kernel: NF Channel 5765 Chain 2  measured latest ctl:-106 ext:-106  capped median ctl:-106 ext:-106
May 12 06:13:35 SW CH user.warn kernel: wifi1: 3774843193 : stuck beacon (missed 3) scanning 0, syncbeacon 0, sc_beacons 1,sc_isCaldone: 1
May 12 06:13:35 SW CH user.info kernel: 0x5a 0x46  0x37  0x37
May 12 06:13:41 SW CH user.info kernel: 0x5a 0x46  0x37  0x37
May 12 06:13:45 SW CH daemon.warn Eved: MLME-REPLAYFAILURE.indication(wlan0 AES-CCM keyid=6 unicast RA:addr=f0:b0:52:11:a1:28 TA:addr=3c:9b:d6:fa:f4:84) (pkt-rsc:2120 k->rsc[1]:2146
May 12 06:13:46 SW CH user.warn kernel: NF Channel 5765 Chain 0  measured latest ctl:-106 ext:-103  capped median ctl:-105 ext:-103
May 12 06:13:46 SW CH user.warn kernel: NF Channel 5765 Chain 1  measured latest ctl:-109 ext:-109  capped median ctl:-109 ext:-109
May 12 06:13:46 SW CH user.warn kernel: NF Channel 5765 Chain 2  measured latest ctl:-106 ext:-106  capped median ctl:-106 ext:-106
May 12 06:13:46 SW CH user.warn kernel: wifi1: 3774854388 : stuck beacon (missed 3) scanning 0, syncbeacon 0, sc_beacons 1,sc_isCaldone: 1
May 12 06:13:46 SW CH user.info kernel: 0x5a 0x46  0x37  0x37
May 12 06:13:47 SW CH user.warn kernel: NF Channel 5765 Chain 0  measured latest ctl:-105 ext:-103  capped median ctl:-105 ext:-103
May 12 06:13:47 SW CH user.warn kernel: NF Channel 5765 Chain 1  measured latest ctl:-109 ext:-108  capped median ctl:-109 ext:-109
May 12 06:13:47 SW CH user.warn kernel: NF Channel 5765 Chain 2  measured latest ctl:-106 ext:-106  capped median ctl:-106 ext:-106
May 12 06:13:47 SW CH user.warn kernel: wifi1: 3774855240 : stuck beacon (missed 3) scanning 0, syncbeacon 0, sc_beacons 1,sc_isCaldone: 1
May 12 06:13:47 SW CH user.info kernel: 0x5a 0x46  0x37  0x37
May 12 06:13:48 SW CH user.warn kernel: ath_get_radio_stats:Add counters, tx_errors=5877728 rx_errors=327848 tx_dropped=0 rx_dropped=0
May 12 06:13:48 SW CH user.warn kernel: ath_get_radio_stats:Add counters, tx_errors=2028629 rx_errors=582703 tx_dropped=0 rx_dropped=8
May 12 06:13:49 SW CH user.info kernel: 0x5a 0x46  0x37  0x37
May 12 06:13:49 SW CH user.info kernel: 0x5a 0x46  0x37  0x37
May 12 06:13:51 SW CH user.info kernel: 0x5a 0x46  0x37  0x37
May 12 06:13:51 SW CH user.info kernel: 0x5a 0x46  0x37  0x37
May 12 06:13:51 SW CH user.info kernel: 0x5a 0x46  0x37  0x37
May 12 06:13:57 SW CH user.warn kernel: NF Channel 5765 Chain 0  measured latest ctl:-105 ext:-103  capped median ctl:-105 ext:-103
May 12 06:13:57 SW CH user.warn kernel: NF Channel 5765 Chain 1  measured latest ctl:-109 ext:-109  capped median ctl:-109 ext:-109
May 12 06:13:57 SW CH user.warn kernel: NF Channel 5765 Chain 2  measured latest ctl:-111 ext:-106  capped median ctl:-106 ext:-106
May 12 06:13:57 SW CH user.warn kernel: wifi1: 3774865309 : stuck beacon (missed 3) scanning 0, syncbeacon 0, sc_beacons 1,sc_isCaldone: 1
May 12 06:13:57 SW CH user.info kernel: 0x5a 0x46  0x37  0x37
May 12 06:14:02 SW CH user.info kernel: 0x5a 0x46  0x37  0x37
May 12 06:14:12 SW CH user.info kernel: 0x5a 0x46  0x37  0x37
May 12 06:14:17 SW CH user.warn kernel: ath_get_radio_stats:Add counters, tx_errors=5877750 rx_errors=327848 tx_dropped=0 rx_dropped=0
May 12 06:14:17 SW CH user.warn kernel: ath_get_radio_stats:Add counters, tx_errors=2028651 rx_errors=582703 tx_dropped=0 rx_dropped=8
May 12 06:14:17 SW CH user.debug kernel: v54cf: v54cf_open: inode=c7432c48, filp=c5ce3260
May 12 06:14:19 SW CH user.info kernel: 0x5a 0x46  0x37  0x37
May 12 06:14:19 SW CH user.info kernel: 0x5a 0x46  0x37  0x37
May 12 06:14:22 SW CH user.warn kernel: findchannel:925 Found matching channel for chan(8) chanflag 0x10088 flags(0X10080)
May 12 06:14:22 SW CH user.info kernel: 0x5a 0x46  0x37  0x37
May 12 06:14:22 SW CH user.info kernel: 0x5a 0x46  0x37  0x37
May 12 06:14:22 SW CH user.info kernel: 0x5a 0x46  0x37  0x37
May 12 06:14:38 SW CH user.debug kernel: v54cf: v54cf_open: inode=c7432b08, filp=c5cadec0
May 12 06:14:46 SW CH user.warn kernel: ath_get_radio_stats:Add counters, tx_errors=5877769 rx_errors=327848 tx_dropped=0 rx_dropped=0
May 12 06:14:46 SW CH user.warn kernel: ath_get_radio_stats:Add counters, tx_errors=2028651 rx_errors=582703 tx_dropped=0 rx_dropped=8
May 12 06:14:49 SW CH user.info kernel: 0x5a 0x46  0x37  0x37
May 12 06:14:49 SW CH user.info kernel: 0x5a 0x46  0x37  0x37
May 12 06:14:53 SW CH user.info kernel: 0x5a 0x46  0x37  0x37
May 12 06:14:53 SW CH user.info kernel: 0x5a 0x46  0x37  0x37

[michael_brado]

Hi Jason,

   The radio is reporting high interference.  We have a couple Knowledge Base Articles that might
help explain 'stuck beacons', ie:

https://support.ruckuswireless.com/articles/000003320

[jason_reich]

Hi Michael, 
Yes, we're working on the RF interference, and have seen the stuck beacons.  I can't load the support article, I'm getting a website 500 error here, even after logging in.

Any insight into the meaning of the NF Channel measurement kernel message?

thanks
Jason.

[michael_brado]

NF stands for Noise Floor.  APs see interference, and raise their noise floor to differentiate clients from noise. 

You have too much radiant "noise" (interference) from something near this AP.