Slim laptops arrive now without ethernet but only wifi, so that internet may not be initially available…

Create a USB debian install disk with main packets in it, that is not the internet version, as internet will not be initially available.

dd if=debian......iso of=/dev/sdZ bs=4M status=progress

Add a 3rd partition for various uses on /dev/sdZ3

- Standard install on debian, add EFI partition (512M), and remaining in a btrfs partition mounted on /

- To install more packets from USB /dev/sda1:

mount  /dev/sda1 /media/cdrom/
update /apt/sources.list with :
deb  [trusted=yes] file:/media/cdrom/ stretch  main
apt update
apt install vim

First check that network is available with :

ip a

To get the type of wifi available :

lspci -nn | grep -i network

Find the “good” driver (in some .deb maybe non-free), install it from apt, or maybe from an USB key with :

dpkg -i firmware-xxx

Get information and check it is in use with :

ip a
iwconfig
    et si nécessaire :
ip link set dev wlan0 up
iwlist scan    

Install networking with creating etc/systemd/network/wlp1s0.network

[Match]
Name=wlp1s0

[Network]
DHCP=yes

then /etc/wpa_supplicant/wpa_supplicant-wlp1s0.conf

ctrl_interface=/var/run/wpa_supplicant

network={
        ssid=""
#       ssid="NETGEAR-3D"    note : "" ok for any open network
        pririty=9 # necessary to force its use when   key_mgmt=NONE
        key_mgmt=NONE
}
## generated by wpa_passphrase [ ssid ] [ passphrase ] >> /etc/wpa_supplicant/wpa_supplicant-wlp1s0.conf
network={
        ssid="PCmobile"
        #psk="1234567890"
        psk=c157baf19d12458176ced86fcb08fbe7c3704ef8ac3a4782392cae3b19cdf365
}

If a default domain is needed (“search domain” in old resolv.conf) set it in /etc/systemd/resolved.conf :

[Resolve]
#DNS=
#FallbackDNS=
Domains=couderc.eu

Then :

systemctl stop networking.service
systemctl disable networking.service
systemctl enable systemd-networkd
systemctl enable wpa_supplicant@wlp1s0
systemctl enable systemd-resolved
systemctl start systemd-networkd
systemctl start wpa_supplicant@wlp1s0
systemctl start systemd-resolved
ln -s /run/systemd/resolve/resolv.conf /etc/resolv.conf