Lost connection, no beacons received

RouterOS Wireless Networking
21

I’ve tried everything but nothing helped.

I thought about different thing:
I have two antennas on same holder both connected to different cards in RB433

Finally I’ve tried to disable AP on RB433 and connection drop went away.
After that I’ve thought about reasons - so I switched frequency from 6 to channel 1 on AP and enabled AP but problem came back.

The question is why problem rised after update to R52nM and ROSv4.16? And wasn’t there before?

Is it possible that beacon from AP interferes beacon from AP-bridge on RB411 (main AP), although each broadcast on different frequencies (first and last channel)?

Now I can’t fix cables nor antennas because of weather.
Is there any other way how to fix it?
I thought about temporary switch AP to WDS-slave and disable WDS-station interface. Or add AP (maybe from another manufacturer) as AP-bridge or WDS-station.

22

I have two antennas on same holder both connected to different cards in RB433

Me too.

After that I’ve thought about reasons - so I switched frequency from 6 to channel 1 on AP and enabled AP but problem came back.

Me too.

The question is why problem rised after update to R52nM and ROSv4.16? And wasn’t there before?

I’m on V4.16
Please enable verbose logging on the station router.

/system logging
add topics=wireless,debug action=memory

Then post the log entries after a disconnect.

23

debug log said (before change below):
03:07:02 wireless,info [AP-MAC]@wlan1_CL: lost connection, no beacons received
03:07:04 wireless,debug wlan1_CL: must select network
[some AP-MACs]
…

all 3x in log.

I tried to reduce AP signal strength on RB433 and enable this AP and disconnect problem went away.
But now CPEs of this AP are connected, but no ping or possibility to manage them :frowning:
I don’t think it’s problem of signal strength. It’s strange. Tried to change frequency of AP as was before - not helped.

24

03:07:04 wireless,debug wlan1_CL: must select network

means “frequency hopping”. Please post “/interface wireless” from the station router.

25

The connection to CPEs established :slight_smile: forgot to renew new interface (R52nM) in bridge (wondering how it could work before, without this change)

With default-authentication=no beacon loss happens more rare and 1x in one peace, but they are back when I rise signal strength on AP on RB433 :frowning: .
I suppose that the worst is after me - it’s not ideal, but I’ll watch connection for stability. But I don’t know what to do except change cables when weather permits.

Could help change default-authentication on wlan1_AP?

 0  R name="wlan1_AP" mtu=1500 mac-address=AP2-MAC arp=enabled disable-running-check=no interface-type=Atheros AR5413 radio-name="AP2NAME" mode=ap-bridge ssid="xxx_1" area="" 
      frequency-mode=manual-txpower country=[COUNTRY] antenna-gain=0 frequency=2427 band=2.4ghz-b/g scan-list=default rate-set=default supported-rates-b=1Mbps,2Mbps,5.5Mbps,11Mbps 
      supported-rates-a/g=6Mbps,9Mbps,12Mbps,18Mbps,24Mbps,36Mbps,48Mbps,54Mbps basic-rates-b=1Mbps basic-rates-a/g=6Mbps max-station-count=2007 ack-timeout=dynamic tx-power=10 
      tx-power-mode=all-rates-fixed noise-floor-threshold=default periodic-calibration=default periodic-calibration-interval=60 burst-time=disabled dfs-mode=none antenna-mode=ant-a wds-mode=disabled 
      wds-default-bridge=none wds-default-cost=100 wds-cost-range=50-150 wds-ignore-ssid=no update-stats-interval=disabled default-authentication=yes default-forwarding=yes default-ap-tx-limit=0 
      default-client-tx-limit=0 proprietary-extensions=post-2.9.25 wmm-support=disabled hide-ssid=no security-profile=xxx_def disconnect-timeout=3s on-fail-retry-time=100ms preamble-mode=both 
      compression=no allow-sharedkey=no station-bridge-clone-mac=00:00:00:00:00:00 hw-retries=15 frame-lifetime=0 adaptive-noise-immunity=none hw-fragmentation-threshold=disabled 
      hw-protection-mode=rts-cts hw-protection-threshold=256 frequency-offset=0 

 1  R name="wlan1_CL" mtu=1500 mac-address=CL-MAC arp=enabled disable-running-check=no interface-type=Atheros 11N radio-name="CLNAME" mode=station-wds ssid="xxx" area="" 
      frequency-mode=manual-txpower country=[COUNTRY] antenna-gain=0 frequency=2472 band=2ghz-onlyn scan-list=default rate-set=default supported-rates-b=1Mbps,2Mbps,5.5Mbps,11Mbps 
      supported-rates-a/g=6Mbps,9Mbps,12Mbps,18Mbps,24Mbps,36Mbps,48Mbps,54Mbps basic-rates-b=1Mbps basic-rates-a/g=6Mbps max-station-count=2007 ack-timeout=dynamic tx-power-mode=manual-table 
      periodic-calibration=default periodic-calibration-interval=60 dfs-mode=none wds-mode=disabled wds-default-bridge=none wds-default-cost=100 wds-cost-range=50-150 wds-ignore-ssid=no 
      update-stats-interval=disabled default-authentication=no default-forwarding=yes default-ap-tx-limit=0 default-client-tx-limit=0 proprietary-extensions=post-2.9.25 wmm-support=disabled hide-ssid=no 
      security-profile=xxx_def disconnect-timeout=10s on-fail-retry-time=1s preamble-mode=long compression=no allow-sharedkey=no station-bridge-clone-mac=00:00:00:00:00:00 ht-ampdu-priorities=0 
      ht-guard-interval=any ht-extension-channel=above-control ht-supported-mcs=mcs-0,mcs-1,mcs-2,mcs-3,mcs-4,mcs-5,mcs-6,mcs-7,mcs-8,mcs-9,mcs-10,mcs-11,mcs-12,mcs-13,mcs-14,mcs-15 
      ht-basic-mcs=mcs-0,mcs-1,mcs-2,mcs-3,mcs-4,mcs-5,mcs-6,mcs-7 ht-txchains=0 ht-rxchains=0 ht-amsdu-limit=8192 ht-amsdu-threshold=8192 hw-retries=15 frame-lifetime=0 
      adaptive-noise-immunity=ap-and-client-mode hw-fragmentation-threshold=disabled hw-protection-mode=rts-cts hw-protection-threshold=256 frequency-offset=0
26

All seems ok there, as I expected. It is the station that is causing the challenge. If the station is set to “default-authentication=yes”, then that will cause the interruption. It will occasionally search for a better (less busy) connection.

27

Now wds-station disconnects after 6-50 minutes. (often more frequently)
I noticed this (don’t know if it’s problem):

When I open details of connection in Winbox on RB411 (main AP) RX sometimes varies. For Ex. (1mb → 54mb ->1mb → 48mb → …)

Second notice i’ve made with my Android mobile:
Wifi analyzer of mobile displays The Main AP as 5GHz on unknow channel. It must be mobile error, but other stations are shown in 2.4GHz and with channel number.
speed.png

28

Is wds necessary for your setup? I don’t use it. How many “station-wds” units are on the AP?
What does “/interface wireless registration-table” show for the signal strengths and snr?

I use “mode=ap-bridge” on my APs and “mode=station” on my stations.

Are you still getting this message?

03:07:04 wireless,debug wlan1_CL: must select network

From what I see from experiments, this means “frequency hopping”.

29

Tomorrow I’ll try mode=“station”
This is only one “station-wds” on this AP

Signal strenghts -65 to -60, SNR around 45dB.

Yes, still getting:
02:27:44 wireless,info [AP-MAC]@wlan1_CL: lost connection, no beacons received
02:27:46 wireless,debug wlan1_CL: must select network

Is there any other option how to stop “freq. hopping” ?

30

My signal/snr is real good also. And I was getting disconnects just like that before the “default-authentication=no” change.

I have contacted Mikrotik support about this. I will let you know what they say.

31

Tried mode=“station-pseudobridge” but without “no beacons received” change.
Even though it seems reconnection is faster.

32

I am waiting for a response from Mikrotik support about this issue. When I hear from them, I will post the answer here.

ADD: I heard from support. They seem certain that “default-authentication” has nothing to do with the beacons and disconnects. Maybe they are correct. Could it be that all the noise or interference disappeared the exact time I set “default-authentication=no” almost 6 weeks ago?

They have asked me to set “default-authentication=yes” and see if the problem reappears, so I have. I do not expect anything in the log until this afternoon if the disconnects start again. The disconnects were only happening when that backhaul radio gets busy.

I will let you know what happens.

UPDATE: The result is here:
http://forum.mikrotik.com/t/log-reassociating-disconnected-ok-connected/44784/1

33

Is there any other way how to stabilize connection?
There isn’t way how to set VirtualAP with Nstreme and normal AP without it, is there?

Maybe there is problem within Mirkotik device - disconnection after exactly 6:50 minutes should be a clue.
Try to disable CSMA/CA or completelly replace Mikrotik device to non-Mikrotik client?

34

DeIM, could you contact support about this issue? Include the support output files from AP and station which are made when you see those problems.

35

It must be some HW issue. Maybe connector on new pigtail (MMCX) between miniPCI card and cable to Antenna. Or miniPCI card itself.
The other (non-MT) devices aren’t so sensitive to this regular 6:50 loss of signal.

I disassembled it and found the dielectric is a little closer to the end of central male pin than on pigtail before (u.fl).

Found this on CPE MT:

16:21:55 wireless,debug wlan1_CL: no network that satisfies connect-list,  by default do not connect
16:21:55 wireless,debug wlan1_CL: must select network

Shouldn’t it be issue with b/g/n standards together?

36

replaced pigtail, still getting:

12:54:07 wireless,info [AP-MAC]@wlan1_CL: lost connection, no beacons received 
12:54:08 wireless,debug wlan1_CL: must select network

:frowning:

37

Hi Guys

Have you found a solution to this problem?
It appears i am having the same issue. I have a RB411 Station connecting to an AP Bridge 600m away.
I also have another RB433 AP connected to the same pole.

The errors you were getting are the exact same.

So frustrating, please assist.

38

many ppl have this problem …
its a well known thing… that need a fix…
mt just… don’t see it!!!

39

Mikrotik,

Is there really no fix for this? This has been going on for years now with the wireless package, I had hoped it would be fixed with 5.x but it is still there. Clients with solid connections, good signal strength, good CCQ and I still have logs full of lost connection, no beacons received. These are non WDS links just straight station mode.

Between this and the timing related disconnects of NV2 I am about ready to give up.

40

Hi …

Some preliminary figures. First, second & third scenarios are the same test RB411AR, just swaping cards & functions (AP/client). Fourth and fifth scenarios are production links.

1st scenario: AP R52nM on 2.4GHz, G only & CPE 411AR fitted with R52Hn (AR9220) as client (built in card AR5215 as 2.4AP, G only) => Lost connection, no beacons received.

2nd scenario: AP R52nM on 2.4GHz, G only & CPE 411AR fitted with R52nM (AR9220) as client (built in card AR5215 as 2.4AP, G only) => Lost connection, no beacons received.

3rd scenario: AP R52nM on 2.4GHz, G only & CPE 411AR fitted with R52nM (AR9220) as AP (built in card AR5215 as client, G only) => Up and running for 5 hours now.

4th scenario: AP SR2 on 2.4GHz, G only & CPE WRAp X86 fitted with R52Hn (AR9220) as client => Up and running for 18 days!

5th scenario: AP R52nM on 2.4GHz, G only & CPE 411AR fitted with R52nM (AR9220) as AP (built in card AR5215 as client, G only) => Up and running for 5 days 8 hours and counting.

So …

  • AR9220 is not a good client to AR9220?

  • AR9220 is a good client for SR2?

  • AR5215 is a good client for AR9220/AR5215?

And an already disassembled config … R52Hn (AR9220) as client of a AR5215 = lost connection, no beacons received … but a SR2 as client of the same AP, no problem at all.

BTW, makes no difference at the test 411AR to disable the built in AP.

Signals from -68 to -72, connections speeds from 36 to 54MBps, CCQ > 90, SNR ~40dB.

Regards;