[arch-releng] [archiso] disable 80-net-name-slot.rules for next releng?

[Dave Reisner]

On Tue, May 28, 2013 at 06:34:32PM +0200, Pierre Schmitz wrote:
> Am 28.05.2013 18:14, schrieb Gerardo Exequiel Pozzi:
> > On 05/28/2013 10:42 AM, Thomas Bächler wrote:
> >>>> Proposal: stop using dhcpcd.service, replace with a udev rule that
> >>>> launches instances of dhcpcd at .service for network devices as they
> >>>> appear:
> >>>>
> >>>>   # /etc/udev/rules.d/81-dhcpcd.rules
> >>>>   ACTION=="add", SUBSYSTEM=="net", ENV{SYSTEMD_WANTS}="dhcpcd@$env{INTERFACE}.service"
> >>>>
> >>>> This potentially breaks ordering for units on network.target, but we've
> >>>> never been able to guarantee that anyways using dhcpcd.service.
> >>>>
> >>>> d
> >>>>
> >>>
> >>> Ouch! It does not work :(
> >>>
> >>> Looks like interface at this point is still named eth0, you can see on
> >>> console at boot:
> >>>
> >>> [  OK  ] Started Entropy Harvesting Daemon.
> >>>          Starting Initializes Pacman keyring...
> >>> [  OK  ] Started Login Service.
> >>>          Expecting device sys-subsystem-net-devices-eth0.device...
> >>> [  OK  ] Found device /dev/ttyS0.
> >>>          Starting Serial Getty on ttyS0...
> >>
> >> I think the INTERFACE environment variable is set before the rename. We
> >> can probably fix this - maybe try $name instead of $env{INTERFACE}?
> 
> 
> Interesting. Is it documented somewhere how you can interface with
> systemd from within udev? Or does systemd just "listen" on these env
> vars?

This is a result of systemd listening to udev events and watching
specific tags and properties on interesting devices.

It's documented in daemon(7) under "Device-Based Activation" and
further in systemd.device(5).

d