Systemd-Networkd Debugging – How to Debug Systemd-Networkd

I would like to use systemd-networkd to configure my networking on Ubuntu.

I added an /etc/systemd/netwoek/host0.network file

[Match]
Name=host0

[Network]
Address=10.5.1.1/24
Gateway=10.5.1.254

to configure my host0:

# ip addr
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host
       valid_lft forever preferred_lft forever
2: host0@if14428: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether d6:fa:2e:69:dd:30 brd ff:ff:ff:ff:ff:ff link-netnsid 0
    inet 169.254.229.86/16 brd 169.254.255.255 scope link host0
       valid_lft forever preferred_lft forever
    inet6 fe80::d4fa:2eff:fe69:dd30/64 scope link
       valid_lft forever preferred_lft forever

But, as seen above it is not configured with 10.5.1.1 despite restarting systemd-networkd, enabling it, rebooting. Each time the address is from APIPA (as if there was no DHCP, which is not configured there).

In no other places is networking configured (notably in /etc/network/interfaces, which is empty)