"No beacons received"

RouterOS Wireless Networking
1

I have a 2.4GHz CPE located inside a building where my tower is located – i.e., distance is not a problem. Every so often, it goes into disconnect fits:

10:11:20 wireless,debug wwan-ptp: must select network 
10:11:20 wireless,debug 4C:5E:0C:11:43:26: on 2452 AP: yes SSID AirJohnson caps 0x431 rates 0xff0f basic 0xf MT: yes 
10:11:20 wireless,debug 00:0C:42:6C:1B:17: on 2427 AP: yes SSID Call-623-640-7883(RV) caps 0x431 rates 0xff0f basic 0x101 MT: yes 
10:11:20 wireless,debug 00:0C:42:BA:E7:7F: on 2417 AP: no SSID Call-623-640-7883(MK) caps 0x0 rates 0x0 basic 0x0 MT: no 
10:11:20 wireless,debug 54:A0:50:EE:D2:D4: on 2462 AP: yes SSID Home caps 0x411 rates 0xff0f basic 0xf MT: no 
10:11:20 wireless,debug wwan-ptp: 4C:5E:0C:11:43:26 uses regular 802.11, skip 
10:11:20 wireless,debug wwan-ptp: 00:0C:42:6C:1B:17 uses regular 802.11, skip 
10:11:20 wireless,debug wwan-ptp: 54:A0:50:EE:D2:D4 uses regular 802.11, skip 
10:11:20 wireless,debug wwan-ptp: 00:0C:42:BA:E7:7F not allowed by connect-list 
10:11:20 wireless,debug wwan-ptp: no network that satisfies connect-list,  by default do not connect 
10:11:20 wireless,debug wwan-ptp: 4C:5E:0C:11:43:26 uses regular 802.11, skip 
10:11:20 wireless,debug wwan-ptp: 00:0C:42:6C:1B:17 uses regular 802.11, skip 
10:11:20 wireless,debug wwan-ptp: 00:0C:42:BA:E7:7F uses TDMA, skip 
10:11:20 wireless,debug wwan-ptp: 54:A0:50:EE:D2:D4 uses regular 802.11, skip 
10:11:20 wireless,debug wwan-ptp: no network that satisfies connect-list,  by default do not connect 
10:11:20 wireless,debug wwan-ptp: 00:0C:42:BA:E7:7F uses TDMA, skip 
10:11:20 wireless,debug wwan-ptp: 54:A0:50:EE:D2:D4 does not support short preamble, skip 
10:11:20 wireless,info 00:0C:42:6C:1B:17@wwan-ptp established connection on 2427000, SSID Call-623-640-7883(RV) 
10:11:22 wireless,info 00:0C:42:6C:1B:17@wwan-ptp: lost connection, no beacons received 
10:11:25 wireless,debug wwan-ptp: must select network 
10:11:25 wireless,debug 4C:5E:0C:11:43:26: on 2452 AP: yes SSID AirJohnson caps 0x431 rates 0xff0f basic 0xf MT: yes 
10:11:25 wireless,debug 00:0C:42:6C:1B:17: on 2427 AP: yes SSID Call-623-640-7883(RV) caps 0x431 rates 0xff0f basic 0x101 MT: yes 
10:11:25 wireless,debug 00:0C:42:BA:E7:7F: on 2417 AP: no SSID Call-623-640-7883(MK) caps 0x0 rates 0x0 basic 0x0 MT: no 
10:11:25 wireless,debug 54:A0:50:EE:D2:D4: on 2462 AP: yes SSID Home caps 0x411 rates 0xff0f basic 0xf MT: no 
10:11:25 wireless,debug wwan-ptp: 4C:5E:0C:11:43:26 uses regular 802.11, skip 
10:11:25 wireless,debug wwan-ptp: 00:0C:42:6C:1B:17 uses regular 802.11, skip 
10:11:25 wireless,debug wwan-ptp: 54:A0:50:EE:D2:D4 uses regular 802.11, skip 
10:11:25 wireless,debug wwan-ptp: 00:0C:42:BA:E7:7F not allowed by connect-list 
10:11:25 wireless,debug wwan-ptp: no network that satisfies connect-list,  by default do not connect 
10:11:25 wireless,debug wwan-ptp: 4C:5E:0C:11:43:26 uses regular 802.11, skip 
10:11:25 wireless,debug wwan-ptp: 00:0C:42:6C:1B:17 uses regular 802.11, skip 
10:11:25 wireless,debug wwan-ptp: 00:0C:42:BA:E7:7F uses TDMA, skip 
10:11:25 wireless,debug wwan-ptp: 54:A0:50:EE:D2:D4 uses regular 802.11, skip 
10:11:25 wireless,debug wwan-ptp: no network that satisfies connect-list,  by default do not connect 
10:11:25 wireless,debug wwan-ptp: 00:0C:42:BA:E7:7F uses TDMA, skip 
10:11:25 wireless,debug wwan-ptp: 54:A0:50:EE:D2:D4 does not support short preamble, skip 
10:11:25 wireless,info 00:0C:42:6C:1B:17@wwan-ptp established connection on 2427000, SSID Call-623-640-7883(RV) 
10:11:27 wireless,info 00:0C:42:6C:1B:17@wwan-ptp: lost connection, no beacons received 
10:11:30 wireless,debug wwan-ptp: must select network

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When it is connected, it shows a signal of -57/-62 and CCQ of 70/94% from the CPE side, with S/N 48dB, so again, this is not a signal problem. The only odd thing about this CPE is that it is a “relay” unit (AirJohnson is a 2.4GHz AP in the same case) but the frequencies are separated. There are no other signal sources nearby on the same frequencies. The “MK” tower, which is close in frequency, is about a mile distant, and “Home” is some neighbor’s WiFi unit.

This morning, the fit lasted 12 minutes, and caused the tower to virtually lock up for other users.

None of the controls in /int wireless seem to control connection retry time, only packet retry time.

What can be done about this?

2

I’m surprised at no responses. Is the question too hard, or too easy?

The “Wireless Debug Log” reference mentions this error message only in connection with WDS, and I’m not using WDS. I am using station-bridge mode, however, which is sort of similar; so I’m going to try station (only) mode and see if the problem goes away. Meanwhile, if anyone has any ideas, I’d welcome them.

3

Ive seen similar fits in 5ghz in station mode with zero noise in good signal in multiple deployments. It was fed from a mikrotik AP that serviced both wifi clients and a station bridge in both instances.

I had no luck solving it. I ended up putting a dedicated AP just for that station bridge and it stopped doing it. the other one still does it. my assumption is that the AP is/was too busy servicing its mixed clients to talk to the station bridge and it looses connectivity.

4

What I am seeing is not exactly a station losing connectivity for “no beacons” – it loses connectivity for some random reason (power outage, etc.) and when it tries to re-register, it consistently fails for many minutes because of “no beacons.” Once it successfully reconnects, it will stay running for a day or a week or more, but during those ten minutes or so, it beats up the AP performance severely.

5

I have witnessed the same behaviour, on a regular 2.4Ghz AP induced by a laptop (atom) wireless card. Have you checked the CPE?

6

The CPE is an RB912UAG-2HPnD. I expect that it ought to work and play well with the RB433/R52Hn AP.

7

Sure, but what I mean is it could be faulty, damaged… specially if its getting powered off abruptly several times a day, that could lead to NAND corruption and all kind of weirdness. I’d try a reset to no defaults then load its config to see if the problem persists.

8

Unfortunately, that requires physical access to the unit, so I’ll have to try that next time someone is in residence there.

One thing I’ve established is that changing the WWAN from station-bridge to station hasn’t eliminated the problem. :frowning: