Community discussions

MikroTik App
 
woro
Member Candidate
Member Candidate
Topic Author
Posts: 104
Joined: Sun May 24, 2015 12:47 am

flipping wireless client

Wed Apr 25, 2018 11:56 am

Hi,

I have a small capsman setup with three CAPs but running into user visible issues with a wifi client. It seems to me like it switches between two CAPs very often which also results in reported breaking connections which I do not really expect with capsman at all.

The logging when that happens looks like this:
08:25:31 interface,warning ether4-Office: bridge port received packet with own address as source address (cc:2d:e0:c2:cf:8e), probably loop 
08:25:35 dhcp,info default assigned 192.168.250.120 to 2C:0E:3D:26:75:C7 
08:26:18 caps,info [::ffff:192.168.250.251:38207,Join,CAP-6A347E5C9611] joined, provides radio(s): CC:2D:E0:C2:CF:8E,CC:2D:E0:C2:CF:8F 
08:26:18 caps,info dg-2g: selected channel 2452/20/gn(20dBm) (fixed) 
08:26:18 caps,info dg-5g: selected channel 5180/20-Ceee/ac/P(23dBm) (fixed) 
08:26:26 caps,info 2C:0E:3D:26:75:C7@dg-2g connected, signal strength -62 
08:26:26 caps,info 2C:0E:3D:26:75:C7@eg-2g disconnected, registered to other interface 
08:26:28 interface,warning ether4-Office: bridge port received packet with own address as source address (cc:2d:e0:c2:cf:8e), probably loop 
08:26:34 interface,warning ether4-Office: bridge port received packet with own address as source address (cc:2d:e0:c2:cf:8e), probably loop 
08:26:35 caps,info 2C:0E:3D:26:75:C7@dg-2g disconnected, interface disabled 
08:26:38 caps,info 2C:0E:3D:26:75:C7@eg-2g connected, signal strength -77 
08:26:45 dhcp,info default deassigned 192.168.250.120 from 2C:0E:3D:26:75:C7 
08:26:45 dhcp,info default assigned 192.168.250.120 to 2C:0E:3D:26:75:C7 
08:26:58 caps,info [::ffff:192.168.250.251:49277,Join,CAP-6A347E5C9611] joined, provides radio(s): CC:2D:E0:C2:CF:8E,CC:2D:E0:C2:CF:8F 
So from that log it almost looks like the CAP-6A347E5C9611 loses connection to capsman and that is the reason why the client jumps around?
Is this caused by the loop warning? Both CAPs are connected to capsman via that ether4-Office interface and the reported source address is one of the two wireless interfaces of the CAP which is reported to join frequently.
Any idea what happens here and what would cause it?
 
woro
Member Candidate
Member Candidate
Topic Author
Posts: 104
Joined: Sun May 24, 2015 12:47 am

Re: flipping wireless client

Wed Apr 25, 2018 12:15 pm

ok, so it's really the cap losing connection:
log from the cap
08:26:35 caps,info CAP disconnected from MikroTik (::ffff:192.168.250.254:5246) 
08:26:37 caps,info CAP selected CAPsMAN MikroTik (4C:5E:0C:06:EA:46/6/0) 
08:26:57 caps,info CAP connect to MikroTik (4C:5E:0C:06:EA:46/6/0) failed: timeout 
08:26:57 caps,info CAP failed to join MikroTik (4C:5E:0C:06:EA:46/6/0) 
08:26:57 caps,info CAP selected CAPsMAN MikroTik (::ffff:192.168.250.254:5246) 
08:26:58 caps,info CAP connected to MikroTik (::ffff:192.168.250.254:5246), CommonName 'CAPsMAN-4C5E0C06EA44' 
08:26:58 caps,info CAP joined MikroTik (::ffff:192.168.250.254:5246) 
the other cap does not have the same issue while it's connected just to a different switch port behind ether4-Office.
I cannot explain the connectivity issues so far :-(
 
woro
Member Candidate
Member Candidate
Topic Author
Posts: 104
Joined: Sun May 24, 2015 12:47 am

Re: flipping wireless client

Wed Apr 25, 2018 12:22 pm

And even more information.
The whole thing seems to only happen when this certain device 2C:0E:3D:26:75:C7 moves to this certain CAP. I'm not sure if it only happens on 2G or also the 5G interface. At least there is another device registered at 5G permanently which does not trigger the behaviour.
The hardware is a hAP ac^2.
 
woro
Member Candidate
Member Candidate
Topic Author
Posts: 104
Joined: Sun May 24, 2015 12:47 am

Re: flipping wireless client

Wed Apr 25, 2018 12:53 pm

Latest summary after more testing:
Whenever a client connects to the 2G interface on the CAP it loses connection to capsman. Problably because of
08:26:28 interface,warning ether4-Office: bridge port received packet with own address as source address (cc:2d:e0:c2:cf:8e), probably loop
?

This warning only reports the 2G interface always so I think this might be the reason for capsman to disconnect as soon as a wifi client connects to that interface?
Still I do not get what the warning means. The interface's data path is the local bridge which also contains ether4-Office.
 
User avatar
vecernik87
Forum Veteran
Forum Veteran
Posts: 882
Joined: Fri Nov 10, 2017 8:19 am

Re: flipping wireless client

Wed Apr 25, 2018 1:04 pm

I had similar issue (with disconnection, not caps/capsman) when i used same config for several devices and my virtual wlan accidentally used same MAC. (because config was exported from first device and i didn't notice this)

Try to check, if all interfaces have unique MAC. (simple /interface print should give you list of all MAC's within one device)
 
woro
Member Candidate
Member Candidate
Topic Author
Posts: 104
Joined: Sun May 24, 2015 12:47 am

Re: flipping wireless client

Wed Apr 25, 2018 4:10 pm

Indeed the wlan1 interface and a vlan bridge share the same MAC. No idea how that happened but also stupid question

wlan1 wlan 1500 1600 2290 CC:2D:E0:C2:CF:8E
8 R bridge-vlan bridge 1500 1598 CC:2D:E0:C2:CF:8E

The bridge does not seem to allow me to change the MAC? At least not in Winbox.
And the MAC itself seems to be the legal one for the wlan1 interface. I actually could change it to something but not sure what the "right way" to fix is.
 
woro
Member Candidate
Member Candidate
Topic Author
Posts: 104
Joined: Sun May 24, 2015 12:47 am

Re: flipping wireless client [SOLVED]

Wed Apr 25, 2018 8:53 pm

Found the issue. The wlan1 interface was locally part of the wrong bridge (actually not really as it was controlled by CAPsMAN and even if it would be a local interface it would be correct on that bridge). The bridge then decided to use exactly the MAC of the wlan1 interface while there would have been other better choices ;-) At the same time CAPsMAN also uses the local interface's MAC and so the same MAC was somehow local on the CAPsMAN and coming from the CAP at the same time. Now I've put the wlan1 into another not used bridge locally to avoid bridge using exactly this MAC.
 
User avatar
vecernik87
Forum Veteran
Forum Veteran
Posts: 882
Joined: Fri Nov 10, 2017 8:19 am

Re: flipping wireless client

Thu Apr 26, 2018 1:34 am

It is common that bridge use same MAC as one of devices connected to it (the lowest one to be specific). You can disable it by setting admin-mac (or "Admin MAC address" in winbox) manually.
Having same MAC for interface and bridge (where this interface is connected) does not usually cause issues. However, if same MAC appears in two different devices, they will under some circumstances incorrectly detect loop and disable connection for a while.

Glad you found the issue :)

Who is online

Users browsing this forum: jerogabe, neki, synchro, vkp and 27 guests