Community discussions

MikroTik App
 
samuellsk
newbie
Topic Author
Posts: 30
Joined: Tue Dec 10, 2013 9:54 am

mikrotik wifi roaming

Thu Apr 20, 2023 4:27 pm

Hellou

we are in the process of choosing wifi device to be acting as a client. So i ve picked up RBD52G-5HacD2HnD. Setup it to connect to wifi thats being run by unifi and another test ground is run by ruckus. They consis of 3 aps in triangle each about 10m away and there are rack shelfs.
Both of which support roaming of the wireless clients.

As far as i ve read , mikrotik (client) does not support the handover between ap devices , and as a client he needs to be set to do the roaming himself. Which was enabled and disabled AP roaming on both testing grounds - this proven to be right call , cause when tested the other way (mikrotik not doing roaming but leaving it to aps , roam or rather rude disconnect and reconnect took 7 seconds)

So the mikrotik client is being driven around on a robot and when he roams he roams according to the logs in 00 or 01 seconds. Which is good.
However before he even starts to roam (a assume -70 signal is its limit) the ping is going from 5-10ms to 50 , 100 , 300 , 400. This state is taking about 7 - 9 seconds. After that he roams (00 to 01 second according to the log).

What is troubelling is that period before roam. We are running tests against rabbit server and it seems for him that "increasing latency" period is dead end for him. As the time between sent message and read those same message goes in seconds (like 7-8 sometimes 9 seconds ).

I did not found any mechanism to roam faster, i ve increased the 5ghz datarate from 6 to 12mbps as its minimum , and that did not helped - cause i wanted him to start roaming faster / sooner.

Or maybe i m using wrong device all together. Any recommendadtions , maybe tips ?

Thank you.
 
Kanta
just joined
Posts: 17
Joined: Tue May 15, 2018 7:54 pm

Re: mikrotik wifi roaming

Thu Apr 20, 2023 5:21 pm

make sure your scan list only has the frequencies that are on the APs, the smaller the scan list, the faster the scan time.

Make sure station-roaming is enabled on the ac2.

I would set the 3 AP frequencies to 5180, 5200, 5220 and the scan list on the ac2 to 5180,5200,5220 that should speed up the process by lowering the background scan time and latency delay from when station-roaming does what it is supposed to do and test it then.

Might be able to use connect/access lists on the client/ap or something, but I never had any luck with that.

We had a lot of issues when mixing tp-link and mikrotik devices in a large warehouse. We tried using hap-lite for aps and they had some weird issue where they would remember your wifi mac address and keep advertising it to to all other switches even when you connected a different one, using hapac2 made that transition faster and replacing tp-links with hapac2 solved the rest of our problems even on older scanners.

Meanwhile we have huge hotel running the wifi on mikrotik, all cap ac and some hapac2 all connected to a central crs328 and the roaming was perfect. No issues, 300ms spike here or there when switching from ap to ap, but the voice calls were working just fine. No complaints so far.
Last edited by Kanta on Thu Apr 20, 2023 9:02 pm, edited 2 times in total.
 
User avatar
bpwl
Forum Guru
Forum Guru
Posts: 2978
Joined: Mon Apr 08, 2019 1:16 am

Re: mikrotik wifi roaming

Thu Apr 20, 2023 6:13 pm

MT client is indeed not doing pre-registration to have fast roaming. But I have never seen 7 seconds , as time needed to roam. Not even with RADIUS authentication.

How to make roaming very slow or faster? My experiences ...

- on AP, use "access list" to force disconnect, but when you set "signal out of range" to a large value (larger than the default 30s) the disconnect will only happen later (too late)
- "station-roaming" is for the client device only. Not used if set on the hAP ac2, if that is the AP in the setup. With station-roaming enabled the client will periodically scan for a better AP with the same SSID. With a weaker signal, the scan happens more often. During this scan the client may lose it's connection. (So if there is only one AP, this setting creates avoidable uncontrolled disconnects The same disconnect happens sometimes when you do background scan in the client interface while connected.)
- on station , use "connect list" to search a limited set of AP 's, not "access lists". Sequence matters, the first succesfull is used.
- You will confuse the backbone network and switches MAC tables, if you set the "disconnect timeout" value to a large time in 'advanced' (larger than the 3 sec default), all that time the AP will claim that the client is still there when it's gone, while trying to send that last packet. This will maintain the MAC tables in the switches to still point to this AP, where the client was seen, but is gone some time ago. The client connected to another AP might immediatly correct those switch MAC tables.
- Different AP's with the same SSID should lead to the same L2 LAN network. Then there is no DHCP renewal, or even worse, change of IP address.

There are other timings in this roaming that I do not have under control, and they are not visible as disconnected times in a syslog collected wifi LOG. Data flow is still someting else than wifi disconnect/connect/associate which is very fast according to the syslog.collection.
 
samuellsk
newbie
Topic Author
Posts: 30
Joined: Tue Dec 10, 2013 9:54 am

Re: mikrotik wifi roaming

Thu Apr 20, 2023 8:03 pm

make sure your scan list only has the frequencies that are on the APs, the smaller the scan list, the faster the scan time.

Make sure station-roaming is enabled on the ac2.

I would set the 3 AP frequencies to 5180, 5200, 5220 and the scan list on the ac2 to 5180,5200,5220 that should speed up the process by lowering the background scan time and latency delay from when station-roaming does what it is supposed to do and test it then.

Might be able to use access lists on the client or something, but I never had any luck with that.

We had a lot of issues when mixing tp-link and mikrotik devices in large warehouse. We tried using hap-lite for aps and they had some weird issue where they would remember your wifi mac address and keep advertising it to to all other switches even when you connected a different one, using hapac2 made that transition faster and replacing tp-links with hapac2 solved the rest of our problems even on older scanners.

Meanwhile we have huge hotel running the wifi on mikrotik, all cap ac and some hapac2 all connected to a central crs328 and the roaming was perfect. No issues, 300ms spike here or there when switching from ap to ap, but the voice calls were working just fine. No complaints so far.
will try the frequency trick.

well the problem is not a linux or even better windows client, which was supporting the fast roam since xp i think ? it was def in win 7. The mkt is the client however (or any other suitable device , but so far i ve tried mkt only)
 
samuellsk
newbie
Topic Author
Posts: 30
Joined: Tue Dec 10, 2013 9:54 am

Re: mikrotik wifi roaming

Thu Apr 20, 2023 8:08 pm

MT client is indeed not doing pre-registration to have fast roaming. But I have never seen 7 seconds , as time needed to roam. Not even with RADIUS authentication.

How to make roaming very slow or faster? My experiences ...

- on AP, use "access list" to force disconnect, but when you set "signal out of range" to a large value (larger than the default 30s) the disconnect will only happen later (too late)
- "station-roaming" is for the client device only. Not used if set on the hAP ac2, if that is the AP in the setup. With station-roaming enabled the client will periodically scan for a better AP with the same SSID. With a weaker signal, the scan happens more often. During this scan the client may lose it's connection. (So if there is only one AP, this setting creates avoidable uncontrolled disconnects The same disconnect happens sometimes when you do background scan in the client interface while connected.)
- on station , use "connect list" to search a limited set of AP 's, not "access lists". Sequence matters, the first succesfull is used.
- You will confuse the backbone network and switches MAC tables, if you set the "disconnect timeout" value to a large time in 'advanced' (larger than the 3 sec default), all that time the AP will claim that the client is still there when it's gone, while trying to send that last packet. This will maintain the MAC tables in the switches to still point to this AP, where the client was seen, but is gone some time ago. The client connected to another AP might immediatly correct those switch MAC tables.
- Different AP's with the same SSID should lead to the same L2 LAN network. Then there is no DHCP renewal, or even worse, change of IP address.

There are other timings in this roaming that I do not have under control, and they are not visible as disconnected times in a syslog collected wifi LOG. Data flow is still someting else than wifi disconnect/connect/associate which is very fast according to the syslog.collection.
mkt is not the AP as was in the original post stated, so no access list.
connect-list led only to rabbit reconnects from original 7 sec to 15 or more. As this mechanics do not roam but as i stated before forcefully disconnect mkt and connect it to another ap. its not doing the background scan and roaming as you would expect it. When tested -67..120 was used and out of range 00:00:05

ips are static just in case it wants to be doing the dhcping...
 
samuellsk
newbie
Topic Author
Posts: 30
Joined: Tue Dec 10, 2013 9:54 am

Re: mikrotik wifi roaming

Tue Apr 25, 2023 9:52 am

Just a heads up.

limiting AP solution to only 4 frequencies and mkt clients using scan list of those 4 freq did seems to help lowering the rabbit issue by half, but they are still there.
As the mikrotik client was never designed in mind to be used for fast roaming , most likely we ll go with some other solution.

Thank you all for your help.
 
hebinglong
just joined
Posts: 1
Joined: Mon May 15, 2023 5:10 pm

Re: mikrotik wifi roaming

Fri Aug 04, 2023 5:37 pm

Are you found any better solution for fast roaming?

Same trouble as you, roaming time is importaint for me.

Or any parameter for setting 'background scan" frequency? I can accept for lose some network package when background scan.

Or can we using script to do that?

any help? thanks.
 
samuellsk
newbie
Topic Author
Posts: 30
Joined: Tue Dec 10, 2013 9:54 am

Re: mikrotik wifi roaming

Thu Nov 30, 2023 2:39 pm

Are you found any better solution for fast roaming?

Same trouble as you, roaming time is importaint for me.

Or any parameter for setting 'background scan" frequency? I can accept for lose some network package when background scan.

Or can we using script to do that?

any help? thanks.
i know i m late to the party.... NO there is still no roaming
i for now i m using 4 frequencies and scanlist. But being disconnected for a second / two and rabbit is taking even longer to start sending messages again is simply a dead end i m now in.

i m playing with the idea in my head using raspberry for a wifi as a bridge , since idea of wds network (for moving robots and for aps forming simply one massive wds ap network with no clients ) was denied by my boss , being too hocus-pocus focused and it can go sideway in the future updates. Which i agree. One bad update by mkt team and hundreads of thousands of euros will go through the chimeny...

Who is online

Users browsing this forum: No registered users and 35 guests