[systemd-devel] Using busybox-udhcpc

[Kay Sievers]

On Wed, Jul 31, 2013 at 1:16 AM, Paul D. DeRocco <pderocco at ix.netcom.com> wrote:
> I have a Yocto-based embedded system (poky-dylan on a Cedartrail Atom),
> which has been modified to use systemd. I've also added Samba 3.6.8 from
> OpenEmbedded. The system has available busybox-udhcpc for a DHCP client, but
> nothing is starting it. If I start it manually, then Samba works fine.
>
> I suppose I could create a simple systemd unit that starts udhcpc with the
> ethernet port's name, but I'd also like to support an external WiFi dongle.
> I've googled and googled, but I can't find out the "right" way to start
> udhcpc, so that it is invoked whenever some new device is detected. Can
> anyone point me to an example, or some document on the web that explains how
> this is normally done?
>
> I also have a Gumstix system with a Yocto-based distro, and it somehow
> starts up its DHCP client, but I can't figure out how. It uses dhclient,
> instead of busybox-udhcpc, but if I knew how dhclient is invoked by the
> networking system, perhaps that would apply to busybox-udhcpc as well.
>
> Any pointers would be greatly appreciated. It's the last thing I need to fix
> (famous last words) before I have fully functioning networking.

Systemd itself has no clue about networking. We might get there some
day, but not any time soon.

People use networkmanager, connman, old sysvinit-like distro cruft,
custom unit files triggered by udev rules, or just run scripts to do
the job.

>From an operating system point of view, general purpose basic network
setup is one of the weakest and badly integrated parts of the entire
stack. There is nothing simple and generally useful available. It's
just a mess, sorry ... :)

Kay