Help with WIFI roaming / Encourage phone to use strongest SSID

Installing and Using OpenWrt
1

I've got 2 OpenWRT routers (1 x Main and 1 * AP) set up with the same SSID/password combination to allow roaming when walking around the house..(I have Fast Transition enabled, it works fine, but I dont think it is relevant to my questio)

Router 1 (Main): MT6000, running SNAPSHOT r28663-83f150fb3f
Router 2 (AP): R7800, running 10:24 Release

The question I've got is, when sat close to the Main router, why does it typically connect to the AP on the other side of the house? I have even turned the "Maximum transmit power" down to 17db on the AP.

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I need to hold the Phone pretty close to the Main router in order for it to connect to the phone.

  • Is there a setting in OpenWRT where you can say "hey, if you drop below X dBm, connect to another AP, if available".
  • Should I lower the AP power further?
  • What else can I do to encourage the "correct" (closest/strongest) router to be used.

For some more info, this is a screenshot when standing next to Router 2 (AP):

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2

Both APs should use the same:

  • underlying network (i.e they are connected to the same router)
  • ssid
  • Encryption
  • Passphrase
    (For both the 2g + 5g radios)

They should have different:

  • channels, non-overlapping
  • Power levels - reduced to minimize the overlapping coverage areas

Do not use 802.11k/v/r unless you have a demonstrated need for it.