feat(os): Let's assume we want a DNS server pushed via DHCP (#1)

setup.sh

@@ -509,7 +509,7 @@ DHCP=ipv4
 IPForward=yes
 
 [DHCP]
-UseDNS=no
+UseDNS=yes
 RouteMetric=10
 EOF
     systemctl enable 'systemd-networkd' --root='/mnt'
@@ -519,6 +519,9 @@ EOF
 function configure_dns () {
     rm '/mnt/etc/resolv.conf'
     ln -s '/run/systemd/resolve/stub-resolv.conf' '/mnt/etc/resolv.conf'
+
+    # Optionally you may want /etc/systemd/network/50-wired.network to use
+    # UseDNS=no and hardcode DNS server(s) here:
     # sed -i 's/^#DNS=.*/DNS=1.1.1.1/' /mnt/etc/systemd/resolved.conf
     systemctl enable 'systemd-resolved' --root='/mnt'
 }