Re: Linux: replacing network-manager with dhcpcd-gtk (or anything else)

[Roy Marples <roy%marples.name@localhost>]

Hi Ottavio

On 08/01/2018 14:10, Ottavio Caruso wrote:
> A few weeks ago I was looking for a Linux distro on which to install
> pkgsrc. I experimented with CentOs but I wasn't very happy, so I gave
> up with pkgsrc altogether and installed Linux Mint Debian edition,
> only because it comes with everything but the kitchen sink, or so I
> thought.
>
> I am terribly irritated by systemd + network-manager interactions. For
> example the network doesn't come up after suspend from resume. I have
> been googling intensively for the last few days and I haven't found a
> cleaner solution than just restarting network manager from the cli. So
> I though of getting rid of NM and install dhcpcd-gtk from pkgsrc,
> because that was working well with NetBSD.
>
> But before doing that, I want to know if I'm doing the right thing and
> not locking myself out. I know that dhcpcd-gtk is a front end to
> dhcpcd and wpa_supplicant.
>
> I do have wpa_supplicant already but it doesn't seem to be using a
> configuration file:
>
> $ ps aux|grep wpa
> root      2923  0.0  0.1  31120  6532 ?        S    Jan05   0:03
> /sbin/wpa_supplicant -u -s -O /run/wpa_supplicant
>
>
> And apparently no dhcpcd:
>
>
> $ ps aux|grep dhcp
> root      6830  0.0  0.2  25404 10220 ?        S    13:47   0:00
> /sbin/dhclient -d -q -sf /usr/lib/NetworkManager/nm-dhcp-helper -pf
> /var/run/dhclient-wlan0.pid -lf
> /var/lib/NetworkManager/dhclient-671d0b1b-65dd-476c-a57f-773e7faeb811-wlan0.lease
> -cf /var/lib/NetworkManager/dhclient-wlan0.conf wlan0

NetworkManager will control starting and stopping wpa_supplicant AND 
configure wpa_supplicant over DBus - hence no configuration file in that 
setup (at least, not for wpa_supplicant). It will also start dhclient.

dhcpcd on the other hand won't do any of that by default.
You are required to start wpa_supplicant via your init system of choice 
OR install the 10-wpa_supplicant hook file for dhcpcd.
It goes without saying the init system needs to start dhcpcd as well.

Here is the bare minimum wpa_supplicant.conf:
# If wheel group does not exist, use root instead
ctrl_interface=/var/run/wpa_supplicant GROUP=wheel
update_config=1

Here is how it looks whilst running on my system:
/usr/sbin/wpa_supplicant -B -M -c /etc/wpa_supplicant.conf
/sbin/dhcpcd -qM

As you're using Debian you don't have the luxury of the -M flag for 
wpa_supplicant so you'll need to specify -i wlan0 instead.

One last piece of advice, disable NetworkManager *before* attempting to 
start wpa_supplicant and dhcpcd as they won't play nicely with each other.

Roy