[systemd-devel] [RFT] DHCPv4 support in networkd

[Tom Gundersen]

On Thu, Jan 2, 2014 at 3:43 AM, Kay Sievers <kay at vrfy.org> wrote:
> On Wed, Jan 1, 2014 at 4:41 PM, Tom Gundersen <teg at jklm.no> wrote:
>> I just pushed the last couple of patches to enable DHCPv4 support in
>> networkd[0]. Testing and feedback would be greatly appreciated.
>>
>> It is still very basic, but I'm personally using it full-time on my
>> laptop (replacing NetworkManager/ConnMan), so it should be complete
>> enough to at least start testing. If you want to use it with wifi (as
>> I'm doing), just (e.g.) enable wpa_supplicant-nl80211 at .service for
>> your device and configure that for your networks manually.
>
> I have a wired e1000e connection to a DSL router.
>
> I removed NetworkManager and added that:
>
>   $ cat /etc/systemd/network/wired.network
>   [Match]
>   Name=enp0s25
>
>   [Network]
>   DHCP=yes
>
>   $ journalctl -b -o short-monotonic -u systemd-networkd.service
>   [    1.318123] lon systemd[1]: Started Network Service.
>   [    3.073097] lon systemd-networkd[205]: Network '(null)' being
> applied to link 'enp0s25'
>   [    3.301739] lon systemd-networkd[205]: Interface 'enp0s25' is up
>   [    4.815708] lon systemd-networkd[205]: Interface 'enp0s25' is connected
>   [    8.943769] lon systemd-networkd[205]: Received config over DHCPv4
>   [    8.952326] lon systemd-networkd[205]: Addresses set for link 'enp0s25'
>   [    8.952614] lon systemd-networkd[205]: Routes set for link 'enp0s25'
>   [    8.952957] lon systemd-networkd[205]: Link 'enp0s25' configured
>
> Any idea why it takes 4 seconds? Do you have any numbers for your setup?

Depending on the network I'm connecting to it takes between 200 ms and
5 seconds (the numbers seem to be stable for any given network). As
far as I have been able to tell we are not doing anything wrong (i.e.,
it simply takes the dhcp server that long to send us a reply). It has
been some time since I tried with debug output from the dhcp library
though, so should re-test to verify.

> And there is a "(null)" in the log output.

Ah, that should be changed (it tries to print the Description).

-t