Merci, j'ai résussi à configurer proprement mon wifi dans /etc/network/intefaces .
Maintenant, je peux arrêter /démarrer mon réseau avec ifdown / ifup .
J'ai un autre pb (mais je vais poster un nouveau sujet).
# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).
# The loopback network interface
auto lo
iface lo inet loopback
# The primary network interface
auto eth0
iface eth0 inet static
address 192.168.1.9
netmask 255.255.255.0
network 192.168.1.0
broadcast 192.168.1.255
gateway 192.168.1.2
# dns-* options are implemented by the resolvconf package, if installed
dns-nameservers 192.168.1.7
dns-search localdomain
test missing-cable
auto wlan0
iface wlan0 inet static
address 192.168.1.10
netmask 255.255.255.0
network 192.168.1.0
broadcast 192.168.1.255
gateway 192.168.1.2
wireless_mode Managed
wireless_essid monessid
wireless_key maclé
wireless_rts 2346
wireless_frag 2346
wireless_nick athlon64.localdomain
wireless_rate auto
~