Greg Wooledge, 18.3.2019 13:30 +0100: > 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.
1) and 2) was already the case on my machine. Nevertheless the service was started before the needed interface was up. That's why I asked in the first place. Judging from the info in the other answers I got, it's obviously known that 1) and 2) are *not* enough to make sure the start of such a service is delayed until the required interfaces are up. -- Regards mks
