Comment 44 for bug 1636912

I've tested Before=network-pre.target; that works fine. However, for the networkd case, systemd-networkd-wait-online.target should ensure that systemd-networkd-resolvconf-update.service has run first otherwise there might a window where interfaces are configured, but DNS is not.

The following change should go against systemd-networkd-wait-online.service

+ # Ensure that DNS is working before reaching online target
+ After=systemd-networkd-resolvconf-update.service