Lost connection, no beacons received

RouterOS Wireless Networking
41

Yes, I fully agree, I posted the same scenarios over a year ago, with the same magical disconnect times.

Always around the 6 minute marker.

That should be a good enough clue for Mikrotik to sort it out, bla bla bla, All these posts to try this and that setting.

Makes no difference what so ever!.

There are hundreds of us out there with the same issue, and many of us that report the same period of time disconnects (approx 6 minutes).

How can it be anything related to a setting requirement, all of us users with same issues, have varying number of stations connected to an Ap, at varying signal levels, with varying background interference.

I have 1 station connected to an AP at -77 (signal) and they have had this problem for over a year, thank god they dont use the phone and by putting the AP frequency in the scan list the disconnect is a fraction of a second.

Now I see that the neighbour to where my tower is placed has started to get the same problem, and he lives 100 metres from the tower.. For years his connection was as solid as a rock, now he suffers the same as the other client.

OOO and BTW, port flapping still exists on 5.4.

42

Did it not occur to anyone that these issues developped after the introduction of the tdma option in the new ROS?
Maybe the new software also makes radio more sensitive and does pick up interference from other sources more easy then before?
Imho the issue is all to do with interference.

I had same problems in my all 5Ghz network (all 20mhz channels in use!) which does make a difference compared to 2,4Ghz due the better channel separation.

What did the trick for me?

  • set ´connect-to´ list in CPE and make two rules. One to connect to AP mac, the second to AP SSID.
  • set ´access-listñ in AP and mention only the CPE’s allowed to connect.
  • Both AP and CPE have ´default auth.´ disabled.
  • set 10Mhz channel width. Although max. throughput might be halved, signal strenthgs are slightly better and thus radio links improves. As long as conn. rate is sufficiant to satisfy CPE traffic demand I have no problem. (24Mb conn. rate guarantees 10-12Mb data througput, which is plenty for 4Mb assigned clients, even for 8Mb assigned client!)
  • set conn. rates on AP to only 2 or 3 rates. 6Mb for basic handshaking etc. and one or 2 that all connected CPE’s can maintain without dropping signal for that rate below -73
  • Any CPE with worse signal than -80 is to be considered ´bad´ anyway. Try to get better than -70. If not possible, use better antenna.
  • Set the AP frequency in the wireless ´Scan List´. This way CPE only works on this frequency.
  • Set Adaptive Noise Immunty in both AP and CPE accordingly.
  • Use NV2 with encryption.
  • Upgrade to ros 5.4. Running on my 220+ CPE network it came without any hickups or issues. Very stable version!

All these settings helped me getting rid of the issue.
I also set a new policy on my network; No more two radio’s in same band on one board. And if a CPE radio has to work in a plastic housing, spraypaint the housing (NOT in front of the antenna!) with a metal paint. It helps keeping foreing signals away from the antenna connector. I did a test and saw 1-2dB diffence! This is rougly 25% less singal!
All little bits help!

After some months struggling my whole network is free of any of the dissconnects I was suffering from. Even close adjacent channels are not giving problems any more.

I don’t think it can be pointed to what setting is actually making the difference. Imho it is the combination of all settings.
I call it ´hardening´ my network agains interferences.
After all, reciever in CPE has to make several decisions on what to do with all kind of packages arriving with different frequencies. So tell him to focus as much as possible to only pick these it shoudl use…

One reason why I think the new ROS versions are more sensible for other signals:
I had two CPE running 4.xx version and associated to AP. Signals where strong due the short distance to AP. (signals at CPE recieved fm AP in the -40 range, distance 150 to 200mtrs).
Now I started to upgrade my network to NV2 able wireless packages. I found that these two (retrospective conclusions) units performed very poor. Also many disconnects etc. I replaced these CPE with other units but the problem persisted. Very low signal strengths, -80 to -90! While I could almost throw a stone to the AP!!!
Than I set the ´Scan List´ parameter in the CPE to make it to listen to the AP frequency. BANG, straight away my good signals were back and the dissconnects stopped!
After switching this setting a couple of times on and off and watching in the wireless status field I found that the CPE with Scan List disabled, was connecting to one of the adjacent frequencies (next down or up 20Mhz channel of AP). Off course this frequency was much weaker than the main one.
If I ran a wireless ´scan´ while the Scan List was disabled, in fact I see three frequencies coming from AP’s mac address all carrying same SSID.
Why now rb decides to pick one of the weak channels and not the strong centre one is not clear to me.
But anyway, setting ´Scan List´ to the right (´centre´) frequency solved the issue.
This problem did never exist on units running post NV2 packages.

Hence my remark in the first sentence of this topic.
One of my conclusion is also that due the freq. range in the 2.4Ghz band it will be much harder to stay out of interference issues than in the 5Ghz band. Before this might not have been such an issue. But when software is now ´better´, it picks up more ´problems´.
It is like your new cabriolet car gives you the problem with your ´toupet´ blowing off your head. On your bicycle you never had that issue. But that is not because the car is now worse. It is only that the new car make it possible to sense experiances you could never before sense at all! :confused:

[and btw, all units that had the port flapping issue on ros 5.1 and 5.1 have no more ´flapping ports´ after the upgrade to 5.4. :wink:
I can’t find a single unit on my network where the log shows any more port ´flaps´…]

43

Well …

What mades me post here, despite being observing this message (no beacons received) from months and believing that this belongs to an old setup which has a OEM only B AR5211 based AP on 2.4 + R52Hn on 2.4 too as client was … I suspected of 5211 spurs, etc.

This setup is 300m from an AP with a 17dBi sector antenna, Only G on channel 13. The AP was on channel 1 + vertical 12dBi sector and the R52Hn client on a 20dBi grid, horizontal.

Ok, pigtails, bla bla bla, the Belden cables I use as jumpers are dual-braid anyway.

Then last week the old WRAP1C was retired after 3 years, on its place there is now a RB411AR (old fashion, UFL).

I swapped the cards, a R52n as AP and the built in as client. Same antennas plus a vertical omni and R52n using both chains as I’ve been trying to solve some multi-beam needs.

Since I boot it up there was not a single message … more than a week stable.

In this meantime, I am preparing another 411AR to another place, another WRAP needs to be retired, mainly after V5.XX where X86 versions on such weak CPU boards was causing some 100% peaks on CPU (mostly management related).

This 411AR was deployed at my back yard, 25dBi grid, to the same AP were the 1st 411AR is connected.

As the new place is a challenge … lots of trees close to AP & client, a lake in the middle, a bunch of propagation tricks, I decided to use the R52Hn with 2 antennas (2 x 25dBi grids), sort of spatial diversity, to improve this PTP link.

What a surprize! Durying the tests (ongoing yet), this 411AR started exibiting no beacons received 6 … 10 times a day. How? There’s not any other 802.11 device around, I’m isolated at countryside, trees all around, and 200m between R52Hn client and R52n AP!

Ok, multipath, group delay because the leaves in between etc. But why the first AP does not have the same problem and is working for more than a week without a single drop?

I suspected of the R52Hn client, replaced it by a R52nM. Both have the same chipsets btw.

Same thing, no beacons received.

Then I swapped cards functions: R52XX as AP, built in as client. Bingo! No more disconnections.

Short (too late) story: I think there’s some issue with 9220 code/driver. With 40dB SNR, CCQ above 85 (95 … 100 most of the time) and no more than 2Mbps loading there is no reason to not receive 100ms cycle beacons.

I described other setups (e.g. SR2 AP x R52Hn client than keeps connected for days without a single drop etc).

I’ll build a matrix … card types x error messages.

And - btw - UBNT clients (nano2, nano2 M, bullet2) that are more exposed to interference than R52XX clients keep connected for days.

Regards;

44

Rudy, Mramos, thanks both for input, but dont want to drift too far off thread.

I want to stay on thread regarding the period of disconnect, and besides I would like to know WHY.

The common disconnect time is around 6mins 52 seconds, or a multiple thereof. And if you look at the posts of others, you will see that the disconnect period is more or less the same.

In the following data, you can see clearly the periods, and bear in mind that these are during the middle of the night, finally finishing off with a single “port flap” on version 5.4!!

I have taken a lot of time to edit the log of my mac and its channel and to colourise some fields to make it clearer to understand, I spend a few minutes editing the text, I have not edited all the relevant data, I just havent got the time.. But its clear from the first page that I edited, that the pattern of disconnects remains the same..

So what is it in the firmware that is relevant to 412 seconds! or there abouts!!




MMM MMM KKK TTTTTTTTTTT KKK
MMMM MMMM KKK TTTTTTTTTTT KKK
MMM MMMM MMM III KKK KKK RRRRRR OOOOOO TTT III KKK KKK
MMM MM MMM III KKKKK RRR RRR OOO OOO TTT III KKKKK
MMM MMM III KKK KKK RRRRRR OOO OOO TTT III KKK KKK
MMM MMM III KKK KKK RRR RRR OOOOOO TTT III KKK KKK

MikroTik RouterOS 5.4 (c) 1999-2011 http://www.mikrotik.com/




(87 messages not shown)
jan/02/1970 00:00:18 system,error,critical router rebooted without proper shutdo
wn, probably power outage
jan/02/1970 00:00:18 system,error,critical router rebooted without proper shutdo
wn, probably power outage
jan/02/1970 00:00:18 system,error,critical router rebooted without proper shutdo
wn, probably power outage
jan/02/1970 00:00:18 system,error,critical router rebooted without proper shutdo
wn, probably power outage

jun/05 02:34:59 wireless,info 00:15:6D:XX:XX:XX@wlan1: failed to connect, on 24XX, association timeout
jun/05 02:35:11 wireless,info 00:15:6D:XX:XX:XX@wlan1 established connection on 24XX, SSID WWS1
jun/05 02:42:03 wireless,info 00:15:6D:XX:XX:XX@wlan1: lost connection, no beacons received
jun/05 02:42:06 wireless,info 00:15:6D:XX:XX:XX@wlan1: failed to connect, on 24XX, association timeout
jun/05 02:42:18 wireless,info 00:15:6D:XX:XX:XX@wlan1 established connection on 24XX, SSID WWS1
jun/05 02:49:10 wireless,info 00:15:6D:XX:XX:XX@wlan1: lost connection, no beacons received
jun/05 02:49:13 wireless,info 00:15:6D:XX:XX:XX@wlan1: failed to connect, on 24XX, association timeout
jun/05 02:49:25 wireless,info 00:15:6D:XX:XX:XX@wlan1 established connection on 24XX, SSID WWS1
jun/05 02:56:17 wireless,info 00:15:6D:XX:XX:XX@wlan1: lost connection, no beacons received
jun/05 02:56:21 wireless,info 00:15:6D:XX:XX:XX@wlan1: failed to connect, on 24XX, association timeout
jun/05 02:56:33 wireless,info 00:15:6D:XX:XX:XX@wlan1 established connection on 24XX, SSID WWS1
jun/05 03:10:31 wireless,info 00:15:6D:XX:XX:XX@wlan1: lost connection, no beacons received
jun/05 03:10:35 wireless,info 00:15:6D:XX:XX:XX@wlan1: failed to connect, on 24XX, association timeout
jun/05 03:10:47 wireless,info 00:15:6D:XX:XX:XX@wlan1 established connection on 24XX, SSID WWS1
jun/05 03:17:39 wireless,info 00:15:6D:XX:XX:XX@wlan1: lost connection, no beacons received
jun/05 03:17:43 wireless,info 00:15:6D:XX:XX:XX@wlan1: failed to connect, on 24XX, association timeout
jun/05 03:17:55 wireless,info 00:15:6D:XX:XX:XX@wlan1 established connection on 24XX, SSID WWS1
jun/05 03:39:00 wireless,info 00:15:6D:XX:XX:XX@wlan1: lost connection, no beacons received
jun/05 03:39:03 wireless,info 00:15:6D:XX:XX:XX@wlan1: failed to connect, on 24XX, association timeout
jun/05 03:39:16 wireless,info 00:15:6D:XX:XX:XX@wlan1 established connection on 24XX, SSID WWS1
jun/05 03:46:08 wireless,info 00:15:6D:XX:XX:XX@wlan1: lost connection, no beacons received
jun/05 03:46:11 wireless,info 00:15:6D:XX:XX:XX@wlan1: failed to connect, on 24XX, association timeout
jun/05 03:46:23 wireless,info 00:15:6D:XX:XX:XX@wlan1 established connection on 24XX, SSID WWS1
jun/05 03:53:15 wireless,info 00:15:6D:XX:XX:XX@wlan1: lost connection, no beacons received
jun/05 03:53:18 wireless,info 00:15:6D:XX:XX:XX@wlan1: failed to connect, on 24XX, association timeout
jun/05 03:53:30 wireless,info 00:15:6D:XX:XX:XX@wlan1 established connection on 24XX, SSID WWS1
jun/05 04:00:23 wireless,info 00:15:6D:XX:XX:XX@wlan1: lost connection, no beacons received
jun/05 04:00:26 wireless,info 00:15:6D:XX:XX:XX@wlan1: failed to connect, on 24XX, association timeout
jun/05 04:00:38 wireless,info 00:15:6D:XX:XX:XX@wlan1 established connection on 24XX, SSID WWS1
jun/05 04:07:30 wireless,info 00:15:6D:XX:XX:XX@wlan1: lost connection, no beacons received
jun/05 04:07:33 wireless,info 00:15:6D:XX:XX:XX@wlan1: failed to connect, on 24XX, association timeout
jun/05 04:07:45 wireless,info 00:15:6D:XX:XX:XX@wlan1 established connection on 24XX, SSID WWS1
jun/05 04:21:45 wireless,info 00:15:6D:XX:XX:XX@wlan1: lost connection, no beacons received
jun/05 04:21:48 wireless,info 00:15:6D:XX:XX:XX@wlan1: failed to connect, on 24XX, association timeout
jun/05 04:22:00 wireless,info 00:15:6D:XX:XX:XX@wlan1 established connection on 24XX, SSID WWS1
jun/05 04:28:52 wireless,info 00:15:6D:XX:XX:XX@wlan1: lost connection, no beacons received
jun/05 04:28:55 wireless,info 00:15:6D:XX:XX:XX@wlan1: failed to connect, on 24XX, association timeout
jun/05 04:29:07 wireless,info 00:15:6D:XX:XX:XX@wlan1 established connection on 24XX, SSID WWS1
jun/05 04:36:00 wireless,info 00:15:6D:XX:XX:XX@wlan1: lost connection, no beacons received
jun/05 04:36:03 wireless,info 00:15:6D:XX:XX:XX@wlan1: failed to connect, on 24XX, association timeout
jun/05 04:36:15 wireless,info 00:15:6D:XX:XX:XX@wlan1 established connection on 24XX, SSID WWS1
jun/05 04:43:07 wireless,info 00:15:6D:XX:XX:XX@wlan1: lost connection, no beacons received
jun/05 04:43:10 wireless,info 00:15:6D:XX:XX:XX@wlan1: failed to connect, on 24XX, association timeout
jun/05 04:43:22 wireless,info 00:15:6D:XX:XX:XX@wlan1 established connection on 24XX, SSID WWS1
jun/05 04:50:16 wireless,info 00:15:6D:XX:XX:XX@wlan1: lost connection, no beacons received
jun/05 04:50:19 wireless,info 00:15:6D:XX:XX:XX@wlan1: failed to connect, on 24XX, association timeout
jun/05 04:50:31 wireless,info 00:15:6D:XX:XX:XX@wlan1 established connection on 24XX, SSID WWS1
jun/05 04:57:22 wireless,info 00:15:6D:XX:XX:XX@wlan1: lost connection, no beacons received
jun/05 04:57:25 wireless,info 00:15:6D:XX:XX:XX@wlan1: failed to connect, on 24XX, association timeout
jun/05 04:57:37 wireless,info 00:15:6D:XX:XX:XX@wlan1 established connection on 24XX, SSID WWS1
jun/05 05:18:43 wireless,info 00:15:6D:XX:XX:XX@wlan1: lost connection, no beacons received
jun/05 05:18:47 wireless,info 00:15:6D:XX:XX:XX@wlan1: failed to connect, on 24XX, association timeout
jun/05 05:18:59 wireless,info 00:15:6D:XX:XX:XX@wlan1 established connection on 24XX, SSID WWS1
jun/05 05:25:50 wireless,info 00:15:6D:XX:XX:XX@wlan1: lost connection, no beacons received
jun/05 05:25:53 wireless,info 00:15:6D:XX:XX:XX@wlan1: failed to connect, on 24XX, association timeout
jun/05 05:26:05 wireless,info 00:15:6D:XX:XX:XX@wlan1 established connection on 24XX, SSID WWS1
jun/05 05:32:55 wireless,info 00:15:6D:XX:XX:XX@wlan1: lost connection, no beacons received
jun/05 05:32:58 wireless,info 00:15:6D:XX:XX:XX@wlan1: failed to connect, on 24XX, association timeout
jun/05 05:33:10 wireless,info 00:15:6D:XX:XX:XX@wlan1 established connection on24XX, SSID WWS1
jun/05 05:47:05 wireless,info 00:15:6D:XX:XX:XX@wlan1: lost connection, no beacons received
jun/05 05:47:08 wireless,info 00:15:6D:XX:XX:XX@wlan1: failed to connect, on 24XX, association timeout
jun/05 05:47:20 wireless,info 00:15:6D:XX:XX:XX@wlan1 established connection on 24XX, SSID WWS1
jun/05 05:54:10 wireless,info 00:15:6D:XX:XX:XX@wlan1: lost connection, no beacons received
jun/05 05:54:13 wireless,info 00:15:6D:XX:XX:XX@wlan1: failed to connect, on 24XX, association timeout
jun/05 05:54:25 wireless,info 00:15:6D:XX:XX:XX@wlan1 established connection on 24XX, SSID WWS1
jun/05 06:01:15 wireless,info 00:15:6D:XX:XX:XX@wlan1: lost connection, no beacons received
jun/05 06:01:18 wireless,info 00:15:6D:XX:XX:XX@wlan1: failed to connect, on 24XX, association timeout
jun/05 06:01:30 wireless,info 00:15:6D:XX:XX:XX@wlan1 established connection on 24XX, SSID WWS1
jun/05 06:22:29 wireless,info 00:15:6D:XX:XX:XX@wlan1: lost connection, no beacons received
jun/05 06:22:32 wireless,info 00:15:6D:XX:XX:XX@wlan1: failed to connect, on 24XX, association timeout
jun/05 06:22:45 wireless,info 00:15:6D:XX:XX:XX@wlan1 established connection on 24XX, SSID WWS1
jun/05 06:29:34 wireless,info 00:15:6D:XX:XX:XX@wlan1: lost connection, no beacons received
jun/05 06:29:37 wireless,info 00:15:6D:XX:XX:XX@wlan1: failed to connect, on 24XX, association timeout
jun/05 06:29:50 wireless,info 00:15:6D:XX:XX:XX@wlan1 established connection on 24XX, SSID WWS1
jun/05 06:36:38 wireless,info 00:15:6D:XX:XX:XX@wlan1: lost connection, no beacons received
jun/05 06:36:41 wireless,info 00:15:6D:XX:XX:XX@wlan1: failed to connect, on 24XX, association timeout
jun/05 06:36:53 wireless,info 00:15:6D:XX:XX:XX@wlan1 established connection on 24XX, SSID WWS1
jun/05 06:43:42 wireless,info 00:15:6D:XX:XX:XX@wlan1: lost connection, no beacons received
jun/05 06:43:45 wireless,info 00:15:6D:XX:XX:XX@wlan1: failed to connect, on 24XX, association timeout
jun/05 06:43:57 wireless,info 00:15:6D:XX:XX:XX@wlan1 established connection on 24XX, SSID WWS1
jun/05 06:50:45 wireless,info 00:15:6D:XX:XX:XX@wlan1: lost connection, no beacons received
jun/05 06:50:49 wireless,info 00:15:6D:XX:XX:XX@wlan1: failed to connect, on 24XX, association timeout
jun/05 06:51:01 wireless,info 00:15:6D:XX:XX:XX@wlan1 established connection on 24XX, SSID WWS1
jun/05 07:04:54 wireless,info 00:15:6D:XX:XX:XX@wlan1: lost connection, no beacons received
jun/05 07:04:57 wireless,info 00:15:6D:XX:XX:XX@wlan1: failed to connect, on 24XX, association timeout
jun/05 07:05:09 wireless,info 00:15:6D:XX:XX:XX@wlan1 established connection on 24XX, SSID WWS1
jun/05 07:11:57 wireless,info 00:15:6D:XX:XX:XX@wlan1: lost connection, no beacons received
jun/05 07:12:00 wireless,info 00:15:6D:XX:XX:XX@wlan1: failed to connect, on 24XX, association timeout
jun/05 07:12:12 wireless,info 00:15:6D:XX:XX:XX@wlan1 established connection on 24XX, SSID WWS1
jun/05 07:19:01 wireless,info 00:15:6D:XX:XX:XX@wlan1: lost connection, no beacons received
jun/05 07:19:04 wireless,info 00:15:6D:XX:XX:XX@wlan1: failed to connect, on 24XX, association timeout
jun/05 07:19:16 wireless,info 00:15:6D:XX:XX:XX@wlan1 established connection on 24XX, SSID WWS1
jun/05 07:21:28 interface,info ether1 link down
jun/05 07:21:56 interface,info ether1 link up (speed 100M, full duplex)

45

This magical 6 or 8 minutes “lost connection, no beacons received” is somewhat better when I changed client to mode=station instead of mode=station-bridge (faster reconnect).
I have to change WiFi cards probably to match each other to avoid this problem completely.