Define a hostname
vi /etc/hostname # short name is fine hostname HOSTNAME # idem vi /etc/hosts # long name FOLLOWED BY short name
Switch back to the old school /etc/network/interfaces (unless you prefer netplan)
apt update apt install net-tools ifupdown rmdir /etc/network/interfaces.d/ #mv /etc/network/interfaces.d/50-cloud-init.cfg /etc/network/interfaces.fuck.the.cloud-init.cfg mv /etc/network/interfaces /etc/network/interfaces.dist
and proceed with a typical Debian network setup
vi /etc/network/interfaces
auto lo
iface lo inet loopback
auto eth0
iface eth0 inet static
address x.x.x.x/xx
gateway x.x.x.x
dns-nameservers x.x.x.x
#dns-nameservers 208.67.222.222 208.67.220.220
#dns-search example.local
Apply, check that your local and caching stub-resolver points to your true validating resolver
systemctl restart networking ifconfig systemd-resolve --status
and see next section for disabling netplan at boot time
Eventually disable UFW
ufw disable
and if you really need to enable system firewalling see Netfilter
systemctl list-unit-files | grep resolv cd /etc/ ls -lhF resolv.conf* mv resolv.conf resolv.conf.dist cat > resolv.conf <<-EOF search example.local nameserver 208.67.222.222 nameserver 208.67.222.220 EOF cat resolv.conf
#systemctl status resolvconf #systemctl stop resolvconf #systemctl disable resolvconf
systemctl status systemd-resolved systemctl stop systemd-resolved systemctl disable systemd-resolved #more shit seen on a bionic dedibox systemctl stop bind9 systemctl disable bind9 systemctl status bind9-resolvconf
In case you get,
RTNETLINK answers: File exists
while restarting networking, look at the logs and proceed against the relevant interface,
ip addr flush dev NETIF
How to install Ubuntu 17.10 (Artful Aardvark) Minimal Server - Page 2 https://www.howtoforge.com/tutorial/ubuntu-minimal-server-install/2/
no symlink for resolv.conf
Comment 7 for bug 548885
https://bugs.launchpad.net/ubuntu/+source/ntp/+bug/548885/comments/7