WiFi roaming with Apple Airport

Many years I used two Apple APs - Extreme and Express connected by ethernet to cover whole house. Both of them had the same SSID, so devices smoothly switched between them without interrupting TCP/IP connections.

Now I installed Turris. It replaced Extreme in place of a router, Extreme was used only as a AP from now. So now there is Turris and two Airports in bridge mode, all of them have the same SSID.

I expected better WiFi coverage, but result was that some devices (two Android phones) had problem with disconnecting after a while. If user selects network manually it connects back successfully. iPhone and computers have no issues.

I tried to tun off Turris’ WiFi APs (two Airports are ony APs there) and problem seems solved.

Do anybody faced it too? Some ideas how to solve it?

Me to.
I had an AirPort Extreme and two airport express connected over Ethernet to extend the wifi. It worked perfect and roaming were smooth between APs.

I replaced the Extreme with the Omnia. I did set up the ombia based on the AE port setting, naming etc. And all traffic to and servers on the inside works perfect.

All but the roaming between stations.
If I have been on one apples airport express 5ghz band with my MacBook Air and move away from it into some other rooms and behind some 40cm concrete walls it should roam over the omnia I would guess.
But it does not.
It still holds on to a poor 7mbit connection even though I’m standing a meter away from the omnia.

It seems as is the mac does not choose the omnia even though the ssid and password are the same. If I disable the wifi and reenable it the omnia is choosen directly.

I was thinking.
My airport express are only n-capable and does not support ac.
And although ac is or at least should be backward compatible to n, could this be one of the reasons?

ac is backward compatible even to a and b if it is not disabled.

There are two different options for roaming in wifi networks.

The simple one is the one you configured. Multiple AP use the same SSID and PSK.

There is another one detailed in 802.11r/k/f. This requires the AP know each other and have some shared secret and some more settings. Roaming from one AP to another one will send your authentication data over ethernet to the next AP and the client will switch without reconnecting.

This setup is possible with OpenWRT but i doubt Apple will allow this.

How to set up roaming with OpenWRT? I was unsuccessful

@Jan_Poboril @CIJOML
I went through the settings on my airports and on the Omnia and did an airport scan in terminal

/System/Library/PrivateFrameworks/Apple80211.framework/Versions/Current/Resources/airport -s

and found that my encryption were different.
The Omnia used WPA2 (PSK/AES,TKIP/TKIP)
while Airports did WPA2 (PSK/AES/AES)

I believe there’s no option to force different ciphers in the airport so I changed the Omnia under Network / Edit for each SSID / Wireless Security

I have following seting:
Encryption WPA2-PSK
Cipher Force CCMP (AES)

After testing some it seems that the roaming is way smoother and not so sticky as before.
The roaming is instant and I could not be happier.