Arch Linux

MayKiller

Member

Registered: 2013-04-08

Posts: 7

dhcpcd not work with NetworkManager 1.0

When I update NetworkManager 1.0, my dhcpcd always not working. It repeat connect and disconnect again and again.
Downgrade networkmanager libnm-glib libnm-gtk to 0.9.10.0 can made this work fine.

systemctl status NetworkManager                                                             19:53:45 
● NetworkManager.service - Network Manager
   Loaded: loaded (/usr/lib/systemd/system/NetworkManager.service; enabled; vendor preset: disabled)
   Active: active (running) since Sat 2015-01-17 19:51:22 CST; 2min 33s ago
 Main PID: 10588 (NetworkManager)
   CGroup: /system.slice/NetworkManager.service
           ├─10588 /usr/bin/NetworkManager --no-daemon
           └─ /usr/bin/dhcpcd -B -K -L -A -G -c /usr/lib/networkmanager/nm-dhcp-helper enp5s0

Using this command is work fine: /usr/bin/dhcpcd -B -K -L -A -G -c /usr/lib/networkmanager/nm-dhcp-helper enp5s0
Using dhcp=dhclient/internal work fine, but can't get IPv6 addr.

It's log of dhcpcd

Jan 17 19:55:44 Mk dhcpcd[18123]: version 6.6.7 starting
Jan 17 19:55:44 Mk dhcpcd[18123]: enp5s0: adding address fe80::ee66:560f:9b2f:298c
Jan 17 19:55:44 Mk dhcpcd[18123]: DUID 00:01:00:01:1a:4a:5b:37:14:cf:92:13:b6:8e
Jan 17 19:55:44 Mk dhcpcd[18123]: enp5s0: IAID 04:61:82:2a
Jan 17 19:55:44 Mk dhcpcd[18123]: enp5s0: rebinding lease of 10.0.0.10
Jan 17 19:55:44 Mk dhcpcd[18123]: enp5s0: leased 10.0.0.10 for 43200 seconds
Jan 17 19:55:44 Mk dhcpcd[18123]: enp5s0: adding route to 10.0.0.0/24
Jan 17 19:55:45 Mk dhcpcd[18123]: enp5s0: soliciting an IPv6 router
Jan 17 19:55:45 Mk dhcpcd[18123]: enp5s0: Router Advertisement from fe80::6eb0:ceff:fe17:571f
Jan 17 19:55:45 Mk dhcpcd[18123]: enp5s0: adding address 2001:470:19:dbf:b4fc:5aa3:e48a:bda/64
Jan 17 19:55:45 Mk dhcpcd[18123]: enp5s0: adding route to 2001:470:19:dbf::/64
Jan 17 19:55:45 Mk dhcpcd[18123]: enp5s0: confirming prior DHCPv6 lease
Jan 17 19:55:45 Mk NetworkManager[10588]: <warn>  the dhcpcd backend does not support IPv6.
Jan 17 19:55:45 Mk dhcpcd[18123]: received signal TERM from PID 10588, stopping
Jan 17 19:55:45 Mk dhcpcd[18123]: enp5s0: removing interface
Jan 17 19:55:46 Mk NetworkManager[10588]: <info>  dhcpcd started with pid 18216

What's wrong about NetworkManager 1.0 and dhcpcd?

Strike0

Member

From: Germany

Registered: 2011-09-05

Posts: 1,487

Re: dhcpcd not work with NetworkManager 1.0

The error your log shows is the same quoted in this +1 year old bug report: https://bugzilla.gnome.org/show_bug.cgi?id=707464
Reading that it seems the NM developers have no interest in fixing the software themselves.

But they probably only forgot about it, perhaps you want to add to the bug to get that it out of the "unconfirmed" state and get a tag for NM version 1.0. added to it.

rsmarples

Member

Registered: 2009-05-12

Posts: 287

Re: dhcpcd not work with NetworkManager 1.0

Jan 17 19:55:45 Mk NetworkManager[10588]: <warn>  the dhcpcd backend does not support IPv6.
Jan 17 19:55:45 Mk dhcpcd[18123]: received signal TERM from PID 10588, stopping
Jan 17 19:55:45 Mk dhcpcd[18123]: enp5s0: removing interface
Jan 17 19:55:46 Mk NetworkManager[10588]: <info>  dhcpcd started with pid 18216

What's wrong about NetworkManager 1.0 and dhcpcd?

The dhcpcd backend in NM probably needs updating.
For starters, dhcpcd has supported IPv6 RA since dhcpcd-5.0.0 (early 2009) and full DHCPv6 support in dhcpcd-6.0.0 (mid 2013).

So it's probably just a false assumption made in the code.

You could try either dhcpcd-gtk or dhcpcd-qt for a system tray based front end which does work with dhcpcd.

Last edited by rsmarples (2015-01-22 20:33:37)

samueldr

Member

Registered: 2009-04-19

Posts: 18

Re: dhcpcd not work with NetworkManager 1.0

I have a workaround for this issue, with the caveat that IPv6 will not work. As the 1.0 release announcement of NetworkManager says, they have added an internal DHCP client to NetworkManager

2: a smaller, faster DHCP client

While it doesn’t do DHCPv6 (yet!) this internal client (based off systemd/connman code) is much faster than dhclient and dhcpcd, and doesn’t consume huge amounts of memory like dhclient.  Use the ‘dhcp=internal’ option in NetworkManager.conf to enable it and let us know how it works.  We’ll be adding DHCPv6 support and enhancing the recognized options in the near future.

Added the dhcp=internal line to the main section of the /etc/NetworkManager/NetworkManager.conf config file.

[main]
dhcp=internal

EDIT: By the way, the gnome bugzilla currently does not load for me. I could not check the referenced issues. (#707464 and #743472).

Last edited by samueldr (2015-01-25 21:10:07)

GogglesGuy

Member

From: Rocket City

Registered: 2005-03-29

Posts: 610

Website

Re: dhcpcd not work with NetworkManager 1.0

The "dhcp=internal" worked for me. I did notice a lot of activity going in the log after that:

n 28 09:40:18  NetworkManager[425]: <info>  (wlp2s0): DHCPv4 state changed bound -> bound
Jan 28 09:40:22 NetworkManager[425]: <info>    address 10.252.2.4
Jan 28 09:40:22  NetworkManager[425]: <info>    plen 25
Jan 28 09:40:22  NetworkManager[425]: <info>    expires in 10 seconds
Jan 28 09:40:22 NetworkManager[425]: <info>    gateway 10.252.2.1
Jan 28 09:40:22 NetworkManager[425]: <info>    nameserver '172.16.1.30'
Jan 28 09:40:22 NetworkManager[425]: <info>    nameserver '172.16.1.50'
Jan 28 09:40:22  NetworkManager[425]: <info>  (wlp2s0): DHCPv4 state changed bound -> bound
Jan 28 09:40:26  NetworkManager[425]: <info>    address 10.252.2.4
Jan 28 09:40:26  NetworkManager[425]: <info>    plen 25
Jan 28 09:40:26  NetworkManager[425]: <info>    expires in 10 seconds
Jan 28 09:40:26  NetworkManager[425]: <info>    gateway 10.252.2.1
Jan 28 09:40:26  NetworkManager[425]: <info>    nameserver '172.16.1.30'
Jan 28 09:40:26  NetworkManager[425]: <info>    nameserver '172.16.1.50'
Jan 28 09:40:26  NetworkManager[425]: <info>  (wlp2s0): DHCPv4 state changed bound -> bound
Jan 28 09:40:30  NetworkManager[425]: <info>    address 10.252.2.4
Jan 28 09:40:30  NetworkManager[425]: <info>    plen 25
Jan 28 09:40:30  NetworkManager[425]: <info>    expires in 10 seconds
Jan 28 09:40:30  NetworkManager[425]: <info>    gateway 10.252.2.1
Jan 28 09:40:30  NetworkManager[425]: <info>    nameserver '172.16.1.30'
Jan 28 09:40:30  NetworkManager[425]: <info>    nameserver '172.16.1.50'
Jan 28 09:40:30  NetworkManager[425]: <info>  (wlp2s0): DHCPv4 state changed bound -> bound

Like every 4-5 seconds...
Is this normal?

Edit:

Never mind, turned out to be some funky company wifi set up.

Last edited by GogglesGuy (2015-01-28 16:28:46)

samueldr

Member

Registered: 2009-04-19

Posts: 18

Re: dhcpcd not work with NetworkManager 1.0

I wouldn't know. I'm not an expert with NetworkManager nor with networking issues, but the "expires in 10 seconds" leads me to believe that either NetworkManager misunderstands the dhcp configuration or the dhcp configuration has a realli short lease time.

I cannot verify with my configuration since I changed to dhclient, as mentioned in another thread regarding similar issues.

Here's the thread and the post:
https://bbs.archlinux.org/viewtopic.php?id=192679
https://bbs.archlinux.org/viewtopic.php … 2#p1496672

Do not forget to install dhclient before changing the configuration and restarting NetworkManager or you may facepalm as I did.

Strike0

Member

From: Germany

Registered: 2011-09-05

Posts: 1,487

Re: dhcpcd not work with NetworkManager 1.0

@samueldr, GogglesGuy: you should open a new thread for that and not hijack this one. Note that the OP opened this specifically because of DHCPv6 problems in the communication between dhcpcd and NM.

samueldr

Member

Registered: 2009-04-19

Posts: 18

Re: dhcpcd not work with NetworkManager 1.0

I should have mentioned that IPv6 does work with dhclient, which is an appropriate workaround IMHO. I referred to the other thread in an attempt to move the conversation unrelated to IPv6 there.