Maxence Dalmais With static routing works: COMPUTER 1 (With only one card): sudo route add default gateway 192.168.2.2 COMPUTER 2 (With two cards): sudo route add default gateway 192.168.3.1 sudo sysctl w net.ipv4.ip_forward=1 COMPUTER 3 (With only one card): sudo route add default gateway 192.168.3.1