On Sat, Mar 16, 2019 at 12:31:50PM +0100, Markus Schönhaber wrote: > It seems that the DHCP server is started while the interface it is > configured to listen on is not yet up and therefore refuses to work. > How can I make sure that the kea-dhcp4-server.service is started no > sooner than after all network interfaces are up?
1) Make sure the interface is marked "auto" and NOT "allow-hotplug" in /etc/network/interfaces. Interfaces that are marked "auto" are required to be up before systemd will consider network-online.target to be satisfied. Interfaces that are marked "allow-hotplug" are NOT required to be up. Note that the Debian installer marks all interfaces except loopback as "allow-hotplug" because it assumes you're using a laptop with a Wifi or removable USB network interface, even if the interface is actually PCI and internal, or even soldered to the motherboard, even if the machine you're installing on is a desktop PC or a rack-mounted server. 2) Make sure your service has [Unit] Wants= network-online.target After= network-online.target either in the native unit file, or in a local drop-in directory. Services with these options will wait for all network interfaces that are marked "auto" to be brought up, before these services can be started. Don't forget the daemon-reload.
