Random connection dropping

RouterOS Beginner Basics
1

Hello,
I’m still having problems with my mikrotik setup (Previous post: http://forum.mikrotik.com/t/mobile-devices-unusable/128011/1 ).
Problem is that from time to time the internet connection drops while a device is still connected to the AP. The problem specially affects mobile devices but PCs and Macs are affected as well.
Now the problem occurs for example when browsing the internet watching videos etc and at that precise moment you can’t event connect to the main router (gateway) @ 192.168.88.1. The device itself stays connected to the AP.

The setup is very simple and i have attached every single devices configuration export as well (except switch). Switches have been assigned static ip addresses and on 192.168.88.5 switch i have ticked the box that says Long PoE in cable.

Also i have attached the network topology:
network_topology.png
Every AC lite box runs 2.4GHz and 5GHz on different channels to make sure they don’t overlap. There is only one exception for that and that is 192.168.88.2 and 192.168.88.3 have 2.4Ghz wifi netowrk set on channel 1 because they are both in different buildings and distance between those buildings is about 30-40 meters. Underground Cat5 cable runs between those buildings as well.

Can anyone please tell me what am i doing wrong? I have been searching for a solution for months now and still got problems. This however is the most stable setup i could get. Default configuration with minor tweaks, as putting the router in bridge mode and assigning static ip address, will not work at all.

SXT-LTE is in default configuration only minor changes:

2

Let’s assume that when interruption occurs and you client connected to the “AP Maja” try to ping all others ap’s and switches, what is the result than?

BTW try login into your switches and check that you don’t have tx/rx errors on ports.

How long is the cable between sw1 and sw2?

3

Will try to ping them on friday when i get back there.

One of the first things i checked was TX/RX errors on switches, there are none.

Cable is around 40-45 meters long.

The same problem happens if connected to 192.168.88.2 (AP Saun) and from there the distance to the switch is about 30 cm and from switch (192.168.88.4) to SXT-LTE (192.168.88.1) the distance is 4 meters.

The SXT-LTE is positioned behind the house (outside) with a perfect line of site to the cellular tower. There is nothing blocking the signal from SXT-LTE to the cellular tower you can see the tower and it is about 3km away

4

Thx for precise information…

Do you have any PC’s which are connected to this network with cable or all devices using internet only over WiFI?

Also i will suggest to check ether1 port on SXT for link downs. Look at Interfaces>ether1>statusTAB>Link downs= number.

5

All devices are using wifi only. Will check for link downs on friday.

6

Any other ideas to check or test?

Should i give more details about something?

If i can’t resolve this is there perhaps a service i can call in estonia that will come and try to inspect and fix the problem on site?

One thing i noticed is that if you have the AP a floor above you (4 meters) (floor has sand and wood) the signal is not poor but given that is only 4 meters away from you should be way better. Also the problem happens when you are connected to the AP next to you like 50 cm.

7

NB!
Do backup from all devices before modifying config…

  1. On router and all APs define IP-address on the bridge1 not interface.
/ip address
add address=192.168.88.x/24 comment=defconf interface=bridge1 network=192.168.88.0
  1. On all APs you have configured dhcp-relay! Why? Disable it because all your devices have connection to the router bridge1 and hence receive IP directly from dhcp-server.
/ip dhcp-relay
add dhcp-server=192.168.88.1 disabled=yes interface=bridge1 name=relay1
  1. Disable RSTP on all of you devices. Including switches.
/interface bridge
set  [ find name=bridge1 ] protocol-mode=none

On switches>
Go to the RSTPtab and switch off RSTP tick on all ports.

Debugging

  1. try to use PC which is connected to the network using cable. So you can understand better where is the problem, is it in WiFi part or somewhere else. From this computer put all devices on ping including outside IP f.e 8.8.8.8. It will help you a lot to understand what is happening.

  2. If problem in WiFi try to disable on all APs 5Ghz and check if problem is solved. If not try same with 2 GHz

  3. Check logs on all mikrotiks, maybe there is something interesting…

8

Why should i disable RSTP ? I don’t really understand that.

9

First of all it’s useless in your network topology, the second one that it can be a source of your current problem…i’m just proposing an ideas what can help you…

10

0 link downs.

11

Did all 3 steps will be monitoring the network closely now.. will let you know..

I did not really understand what RSTP was.. that’s why i asked about it..

12

RSTP - Rapid Spanning Tree Protcol, it help prevent bridge loops in networks.
https://en.wikipedia.org/wiki/Spanning_Tree_Protocol

13

Okay so after about an hour on my tablet the problems came back.

After the changes switches started to say this error on the upgrade page:
ERROR: Could not determine latest version, probably no internet connection. Use manual upgrade.

The problem seems to affect only mobile devices (phones, tablets).. for example my macbook pro that is connected to the 5GHz network does not get these hangs at all. When the problem occurred i could only ping the AP i was connected to not even the gateway.

14

This is all the info that /log print shows me on the AP

oct/31 04:00:18 system,error,critical router was rebooted without proper shutdown 
oct/31 04:00:20 bridge,info "bridge1" mac address changed to B8:69:F4:D7:80:E7 
oct/31 04:00:26 bridge,info hardware offloading activated on bridge "bridge1" ports: ether1 
oct/31 04:00:26 bridge,info hardware offloading activated on bridge "bridge1" ports: ether2 
oct/31 04:00:26 bridge,info hardware offloading activated on bridge "bridge1" ports: ether3 
oct/31 04:00:26 bridge,info hardware offloading activated on bridge "bridge1" ports: ether4 
oct/31 04:00:26 bridge,info hardware offloading activated on bridge "bridge1" ports: ether5 
oct/31 04:00:28 interface,info ether1 link up (speed 100M, full duplex) 
22:08:24 wireless,info 24:1B:7A:94:74:AF@wlan2: connected, signal strength -61 
22:08:30 wireless,info 58:E2:8F:0F:AA:31@wlan2: connected, signal strength -78 
22:22:08 wireless,info 64:A2:F9:F3:79:FB@wlan2: connected, signal strength -70 
22:22:14 wireless,info 64:A2:F9:F3:79:FB@wlan2: disconnected, registered to other device in network 
22:23:02 wireless,info 64:A2:F9:F3:79:FB@wlan2: connected, signal strength -65 
22:23:12 wireless,info 64:A2:F9:F3:79:FB@wlan2: disconnected, received deauth: sending station leaving (3) 
22:26:17 wireless,info 64:A2:F9:F3:79:FB@wlan2: connected, signal strength -58 
22:27:14 wireless,info 78:4F:43:80:2F:87@wlan2: connected, signal strength -69 
22:28:59 wireless,info 64:A2:F9:F3:79:FB@wlan2: disconnected, registered to other device in network 
22:30:11 wireless,info 58:E2:8F:0F:AA:31@wlan2: disconnected, registered to other device in network 
22:32:29 wireless,info 58:E2:8F:0F:AA:31@wlan2: connected, signal strength -76 
22:34:38 wireless,info 64:A2:F9:F3:79:FB@wlan2: connected, signal strength -63 
22:35:15 wireless,info 58:E2:8F:0F:AA:31@wlan2: disconnected, registered to other device in network 
22:37:10 wireless,info 58:E2:8F:0F:AA:31@wlan2: connected, signal strength -68 
22:38:20 wireless,info 58:E2:8F:0F:AA:31@wlan2: disconnected, registered to other device in network 
22:38:44 wireless,info 58:E2:8F:0F:AA:31@wlan2: connected, signal strength -89 
22:39:15 wireless,info 58:E2:8F:0F:AA:31@wlan2: disconnected, extensive data loss 
22:39:42 wireless,info 64:A2:F9:F3:79:FB@wlan2: disconnected, registered to other device in network 
22:40:07 wireless,info 64:A2:F9:F3:79:FB@wlan2: connected, signal strength -72 
22:40:52 wireless,info 58:E2:8F:0F:AA:31@wlan2: connected, signal strength -67 
22:40:53 wireless,info 58:E2:8F:0F:AA:31@wlan2: disconnected, received disassoc: sending station leaving (8) 
22:41:43 wireless,info 24:1B:7A:94:74:AF@wlan2: disconnected, registered to other device in network 
22:47:01 wireless,info 64:A2:F9:F3:79:FB@wlan2: disconnected, group key exchange timeout 
22:47:32 wireless,info 64:A2:F9:F3:79:FB@wlan2: connected, signal strength -67 
22:47:35 wireless,info 24:1B:7A:94:74:AF@wlan2: connected, signal strength -69 
22:47:41 wireless,info 58:E2:8F:0F:AA:31@wlan2: connected, signal strength -72 
22:48:00 wireless,info 58:E2:8F:0F:AA:31@wlan2: disconnected, registered to other device in network 
22:48:01 wireless,info 24:1B:7A:94:74:AF@wlan2: disconnected, registered to other device in network 
22:52:24 wireless,info 58:E2:8F:0F:AA:31@wlan2: connected, signal strength -71 
22:52:27 wireless,info 24:1B:7A:94:74:AF@wlan2: connected, signal strength -61 
22:52:34 wireless,info 24:1B:7A:94:74:AF@wlan2: disconnected, registered to other device in network 
22:53:33 wireless,info 24:1B:7A:94:74:AF@wlan2: connected, signal strength -70 
22:55:46 wireless,info 24:1B:7A:94:74:AF@wlan2: disconnected, registered to other device in network 
22:55:49 wireless,info 24:1B:7A:94:74:AF@wlan2: connected, signal strength -73 
22:57:14 wireless,info 58:E2:8F:0F:AA:31@wlan2: disconnected, registered to other device in network 
22:59:04 wireless,info 24:1B:7A:94:74:AF@wlan2: disconnected, extensive data loss 
22:59:07 wireless,info 24:1B:7A:94:74:AF@wlan2: connected, signal strength -75 
23:07:40 system,info,account user admin logged in from 192.168.88.151 via web 
23:08:30 system,info,account user admin logged in via local 
23:09:16 system,info,account user admin logged in from 192.168.88.226 via web 
23:09:16 wireless,info 58:E2:8F:0F:AA:31@wlan2: connected, signal strength -82 
23:09:16 system,info,account user admin logged in via local
15

From your logs i see that devices is roaming very often in short time for some reason…

f.e this one

22:52:34 wireless,info 24:1B:7A:94:74:AF@wlan2: disconnected, registered to other device in network 
22:53:33 wireless,info 24:1B:7A:94:74:AF@wlan2: connected, signal strength -70 
22:55:46 wireless,info 24:1B:7A:94:74:AF@wlan2: disconnected, registered to other device in network 
22:55:49 wireless,info 24:1B:7A:94:74:AF@wlan2: connected, signal strength -73

Here is good video about WiFi…
https://youtu.be/JRbAqie1_AM?list=PLfpN7Rcw8qidQLXSkigUlwXubjrFCmEM5

16

At the moment logs are clear but there was issues still in the morning when ipad dropped the connection. After a couple of minutes it could connect again (the wifi connection didn’t drop just the internet connection). It could only ping the AP it was connected to and itself, gateway ping timed out.

I have done all 3 changes suggested by user dmitris and also disabled 5GHz network (there is no need for it cause the connection to the internet is only 30 down / 5 up Mbps. Also there is no need for a faster lan connection because devices on the network regularly only connect to the internet not each other and hap ac lite is limited to an 100Mbps ethernet port.

Will monitor the connections and keep this thread up to date (there could be a week delay).

The problem with the switches still does presist: ERROR: Could not determine latest version, probably no internet connection. Use manual upgrade.

The current config is as follows:
192_168_88_2.txt (2.24 KB)
192_168_88_1.txt (3.47 KB)
192_168_88_8.txt (2.31 KB)
192_168_88_6.txt (2.32 KB)
192_168_88_3.txt (2.32 KB)
SwitchMaja (192.168.88.4) config:
192_168_88_4_FORWARDING.png
192_168_88_4_SFP.png
192_168_88_4_LINK.png
192_168_88_4_STATISTICS.png
192_168_88_4_RSTP.png
192_168_88_4_HOSTS.png
192_168_88_4_VLANS.png
192_168_88_4_VLAN.png
192_168_88_4_ERRORS.png
192_168_88_4_ACL.png
192_168_88_4_SNMP.png
192_168_88_4_IGMP_GROUPS.png
192_168_88_4_SYSTEM.png
192_168_88_4_UPGRADE.png

17

SwitchSaun (192.168.88.5) config:
192_168_88_5_FORWARDING.png
192_168_88_5_SFP.png
192_168_88_5_LINK.png
192_168_88_5_STATISTICS.png
192_168_88_5_RSTP.png
192_168_88_5_VLAN.png
192_168_88_5_ERRORS.png
192_168_88_5_ACL.png
192_168_88_5_SNMP.png
192_168_88_5_IGMP_GROUPS.png
192_168_88_5_HOSTS.png
192_168_88_5_VLANS.png
192_168_88_5_SYSTEM.png
192_168_88_5_UPGRADE.png

18

The problem with the switches still does presist: ERROR: Could not determine latest version, probably no internet connection. Use manual upgrade.

Don’t be concerned about this problem now…It’s not related to your current issue at all…

Find you iPad MAC address, than log in your AP’s and look at this parameter > “Wireless>Registration>TX/RX Signal strenght” . If signal strenght for ipad <=-80 dBm (-120..-80 very poor signal, wifi will not work with such parameters). Second one what you should look it’s a signal quality CCQ and SNR

Here is good explanation of SNR,CCQ, … signals.
http://forum.mikrotik.com/t/noise-floor/66971/1
ccq.PNG

19

okay but i would like to get to the bottom of that problem as well.. any ideas on that?

20

In my opinion, Mikrotik switch can’t obtain upgrade software info because you defined a static IP on it. As you can see you defined only static IP but there are no fileds for mask, gateway and dns and hence device don’t know how to reach update server.
P.S
Personally i have same behavior on this device, but it’s not bothering me and a’m doing upgrade manually.