The specificity of my setup, is that the Raspberry won’t be a router but a bridge. DHCP is thus delegated to the main ADSL router and all devices connected to the AP will appear on the same network than other devices. The instructions below are based on a fresh Raspbian lite install so that it can be reproduced easily.
$ sudo apt-get install -y bridge-utils hostapd
To create a bridge, we need to enable ip_forward in the kernel, for that, edit /etc/sysctl.conf and remove comment (#) from the following line :