Easiest way to share internet connection?

kuba_66 · 2014-12-21 10:18:20

Please advise the easiest way to share internet connection. I have a default network setup. Just a desktop with dhspcd for client connections and no network manager. I've inserted another nic and want to share internet connection with another computer.
I followed instructions from "Internet sharing" and "dhcpd" wikis, but these articles aren't foolproof enough for me. I'm getting the following errors:

systemctl status dhcpd4@enp1s9.service
● dhcpd4@enp1s9.service - IPv4 DHCP server on enp1s9
   Loaded: loaded (/etc/systemd/system/dhcpd4@.service; enabled; vendor preset: disabled)
   Active: failed (Result: exit-code) since nie 2014-12-21 10:45:53 CET; 3min 3s ago
  Process: 291 ExecStart=/usr/bin/dhcpd -4 -q -pf /run/dhcpd4.pid %I (code=exited, status=1/FAILURE)

gru 21 10:45:53 jakamal dhcpd[291]: 
gru 21 10:45:53 jakamal dhcpd[291]: 
gru 21 10:45:53 jakamal dhcpd[291]: Not configured to listen on any interfaces!
gru 21 10:45:53 jakamal dhcpd[291]: 
gru 21 10:45:53 jakamal dhcpd[291]: If you think you have received this message due to a bug rather
gru 21 10:45:53 jakamal dhcpd[291]: than a configuration issue please read the section on submitting
gru 21 10:45:53 jakamal systemd[1]: dhcpd4@enp1s9.service: control process exited, code=exited status=1
gru 21 10:45:53 jakamal systemd[1]: Failed to start IPv4 DHCP server on enp1s9.
gru 21 10:45:53 jakamal systemd[1]: Unit dhcpd4@enp1s9.service entered failed state.
gru 21 10:45:53 jakamal systemd[1]: dhcpd4@enp1s9.service failed.

Trilby · 2014-12-21 12:29:17

Which wiki page have you followed? Which method did you use?

I believe you should be following this page but that shows four distinct methods.

ewaller · 2014-12-21 18:54:42

Or, if you prefer a NAT configuration, this page

TheSaint · 2014-12-21 20:09:56

If it is a wired connection between 2 computer, why do you want to use DHCP, better static IP and adjust iptables rule as ewaller pointed.

kuba_66 · 2014-12-24 03:56:50

Trilby, ewaller, The Saint: thanks for your replies.
@Trilby
I followed these wikis: Internet sharing and dhcpd, but yes, a bridge is simpler, so I'll go for it. After Christmas, I think.

Trilby wrote:

(...) but that shows four distinct methods

– that's a bit of a problem, but I'll try method 1.
@TheSaint
I need a socket to plug in various devices without configuring them, so DHCP suits me better.

Going back on all the commands I had issued in following the said wikis was difficult. I hope I've managed to revert to defaults.

TheSaint · 2014-12-24 07:01:09

That's means that every DHCP lease will get its own iptable rule. It will take a bit of scripting, I think.

kuba_66 · 2014-12-28 04:52:35

Setting up a bridge is easy, but i get disconnected by my provider (one computer policy), and it doesn't survive reboots, so I need a NAT anyway.
Trouble is I can't configure my internal interface to use dhcpd on it.
How do I make this persistent:

#ip addr add 139.96.30.100/24 dev eth0

?
In other systems I can configure interfaces with /etc/network/interfaces, but there is no such thing here.
Or in other words, what should be done to enable NAT with DHCP in a few steps? Writing bash scripts doesn't seem a proper solution. I tried using shorewall – it starts, but I can't get it to route and the local interface isn't persistent either. Neither did Firestarter work for me.

Last edited by kuba_66 (2014-12-28 05:12:21)

TheSaint · 2014-12-28 06:52:23

Please try last wiki

kuba_66 · 2014-12-28 12:18:18

@The Saint
Do you mean I should manually assign a static IP to my local interface using Persistent configuration on boot using systemd? It's so ruddy complicated! I am deliberately posting in the Newbie Corner to find a simple solution.
What address, subnet, netmask, etc. should I choose if my primary interface has: inet 192.168.0.11 netmask 255.255.255.0 broadcast 192.168.0.255, if it matters at all?
Or perhaps I could use netctl to set up the interface as suggested here: [link=https://wiki.archlinux.org/index.php/NAT%27ing_firewall_-_Share_your_broadband_connection#IP_configuration]IP configuration[/link], but I am not sure what provides the existing connection. It's a default setup. I think it's dhcpcd. Would it be OK to have one interface configured through dhcpcd and another through netctl?

Last edited by kuba_66 (2014-12-28 12:34:29)

Xyne · 2014-12-28 14:37:48

You may find this useful, at least as an example. I have added a link to the Internet sharing wiki page.

kuba_66 · 2014-12-29 00:37:40

Thank you for sharing, Xyne. Your script is a great way for an ad-hoc dhcp server. I was looking for a more stateful solution.

TheSaint · 2014-12-29 02:45:59

What Xyne pointed and what is in create_ap are the keys to your solutions. It takes some little study.
If you have other distro that semplify your doing, also those may give you the clues.

kuba_66 · 2014-12-29 13:24:15

Thanks for the link to create_ap, Saint. Yes, Xyne's ingredients are very good.

TheSaint · 2014-12-30 03:16:00

You aren't lonely, let us know your developments. If you have more questions don't hesitate to ask for more.
I'm keen to give my best.

Xyne · 2014-12-30 03:49:33

kuba_66 wrote:

Thank you for sharing, Xyne. Your script is a great way for an ad-hoc dhcp server. I was looking for a more stateful solution.

After adapting the subnet launcher script to your needs, you could just create and enable a systemd service file to start and stop it using the ExecStart and ExecStop options, respectively. See the service file manpage for details.

Arch Linux

#1 2014-12-21 10:18:20

Easiest way to share internet connection?

#2 2014-12-21 12:29:17

Re: Easiest way to share internet connection?

#3 2014-12-21 18:54:42

Re: Easiest way to share internet connection?

#4 2014-12-21 20:09:56

Re: Easiest way to share internet connection?

#5 2014-12-24 03:56:50

Re: Easiest way to share internet connection?

#6 2014-12-24 07:01:09

Re: Easiest way to share internet connection?

#7 2014-12-28 04:52:35

Re: Easiest way to share internet connection?

#8 2014-12-28 06:52:23

Re: Easiest way to share internet connection?

#9 2014-12-28 12:18:18

Re: Easiest way to share internet connection?

#10 2014-12-28 14:37:48

Re: Easiest way to share internet connection?

#11 2014-12-29 00:37:40

Re: Easiest way to share internet connection?

#12 2014-12-29 02:45:59

Re: Easiest way to share internet connection?

#13 2014-12-29 13:24:15

Re: Easiest way to share internet connection?

#14 2014-12-30 03:16:00

Re: Easiest way to share internet connection?

#15 2014-12-30 03:49:33

Re: Easiest way to share internet connection?

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