technically the min(max allowable, max possible)....
As here, for example, see above in screenshot where under "Transmit Power:" it show "low, middle, high" and high is selected... I've never seen a factory firmware that does anything other than selecting max out of the box... perhaps the higher end ciscos have some useful "auto" function, but even "auto" probably just means "max" for most firmwares.
forcefully deauthing on received signal strength reportedly works well, APs are often much louder than the phones they serve so they are able to figure out when to drop a client better than the client can figure out to roam... but DHCP is a big hack, I agree it isn't the right approach
Someone raised a point here that once a client is denied DHCP it will give up retrying connection to same SSID.
I am trying to understand if in the case of Max Associations, client retries (to the same SSID) and eventually he connects to another AP.
While I understand OpenWRT will provide the feature, I see issues when running it on all APs.
In many cases we re-use the hardware already available, here not many are openwrt compatible.
In such cases I can buy just one new device for "router" and re-use remaining as AP.
Now If I am buying everything new, then I would buy APs OpenWRT compatible; however even among those there are many caveats on wireless side. I may be wrong but I felt wireless works best on stock firmware. Yes, may be Archer C7 is good with OpenWRT, but it's costly and overkill as AP.
So I am gravitating towards a single powerful OpenWRT device as router (to get the programmable goodness of linux) and remaining as APs with stock firmware.
It's definitely a reasonable strategy, but you might look at something like the TP-Link eap 225 which maybe isn't quite as configurable as the ubiquiti gear, but it's cheaper and has quite a few configs.
Well, an EAP225 costs $70 here in the US
an archer c60 costs $63
so I'm not seeing that same dilemma.
the EAP225 offers you a "controller" based solution, where you can manage all the access points from a single control panel, and Power Over Ethernet for ease of install in a good location not near a plug, like a ceiling or on a wall.
It seems unfortunate that you have such a massive price difference where you are.
In some parts of the world, the price of some devices aren't reasonable. Where I live, for example, Archer C7 is for around $100 new (and there is the factor of wages. That's, by the way, sometimes people cling to low-specs hardware, because devices are not as easy to get as they are in other countries.
Keep them on the same L2 segement/VLAN, so that clients do not need to change ip when roaming.
Install wpad-full and enable 802.11r, so that bss-fast-transition allows smooth roaming between them.
Cut power - especially on the 2.4ghz band with its high range - and try to set a min-rssi. On Openwrt this can be achieved by specifying minimum speeds (or taking them out as someone mentioned above).
On UBNT-gear you could try to hope for 802.11v and 802.11k, but that's a complicated story.
Check the threads that already exist on this topic: