The contents of interfaces.d are as follows:--
ubuntu@juju-gui:~$ ls /etc/network/interfaces.d/ eth0.cfg ubuntu@juju-gui:~$ cat /etc/network/interfaces.d/eth0.cfg # The primary network interface auto eth0 iface eth0 inet dhcp ubuntu@juju-gui:~$
The contents of interfaces.d are as follows:--
ubuntu@juju-gui:~$ ls /etc/network/ interfaces. d/ interfaces. d/eth0. cfg
eth0.cfg
ubuntu@juju-gui:~$ cat /etc/network/
# The primary network interface
auto eth0
iface eth0 inet dhcp
ubuntu@juju-gui:~$