[SOLVED] Wired connection not working, WiFi works fine!

Skipper3121 · 11-12-2018, 08:46 AM

Hello,

I'm on Debian 9 :

Quote:

~$ lsb_release -a
No LSB modules are available.
Distributor ID: Debian
Description: Debian GNU/Linux 9.5 (stretch)
Release: 9.5
Codename: stretch

Quote:

~$ uname -a
Linux Skipper3121 4.15.0-0.bpo.2-amd64 #1 SMP Debian 4.15.11-1~bpo9+1 (2018-04-07) x86_64 GNU/Linux

and had to reboot my computer because of software updates.

Since the reboot only my WiFi connection is working.

Here is the output of ifconfig :

Quote:

$ sudo ifconfig
enp4s0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
ether 50:46:5d:46:c2:ce txqueuelen 1000 (Ethernet)
RX packets 217 bytes 35300 (34.4 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 45 bytes 7081 (6.9 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
device interrupt 19

lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536
inet 127.0.0.1 netmask 255.0.0.0
inet6 ::1 prefixlen 128 scopeid 0x10<host>
loop txqueuelen 1000 (Boucle locale)
RX packets 764 bytes 59532 (58.1 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 764 bytes 59532 (58.1 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0

vmnet1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 192.168.153.1 netmask 255.255.255.0 broadcast 192.168.153.255
inet6 fe80::250:56ff:fec0:1 prefixlen 64 scopeid 0x20<link>
ether 00:50:56:c0:00:01 txqueuelen 1000 (Ethernet)
RX packets 0 bytes 0 (0.0 B)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 160 bytes 0 (0.0 B)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0

vmnet8: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 172.16.133.1 netmask 255.255.255.0 broadcast 172.16.133.255
inet6 fe80::250:56ff:fec0:8 prefixlen 64 scopeid 0x20<link>
ether 00:50:56:c0:00:08 txqueuelen 1000 (Ethernet)
RX packets 0 bytes 0 (0.0 B)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 162 bytes 0 (0.0 B)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0

wlp3s0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 132.227.184.17 netmask 255.255.255.0 broadcast 132.227.184.255
inet6 fe80::a26a:c5d2:23d0:43f2 prefixlen 64 scopeid 0x20<link>
inet6 2001:660:3302:28b8:c414:9666:9b86:ff46 prefixlen 64 scopeid 0x0<global>
ether 60:36:dd:ae:55:51 txqueuelen 1000 (Ethernet)
RX packets 27854 bytes 25041877 (23.8 MiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 10391 bytes 1820804 (1.7 MiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0

We clearly see that my enp4s0 (eth0) interface doesn't have an IP address. If I replug my ethernet cable I'll have a temporary IPv6 address for a while then it'll disappear, here is an example :

Quote:

enp4s0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet6 fe80::c29:1f46:854a:7c5a prefixlen 64 scopeid 0x20<link>
ether 50:46:5d:46:c2:ce txqueuelen 1000 (Ethernet)
RX packets 312 bytes 51672 (50.4 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 113 bytes 17536 (17.1 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
device interrupt 19

lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536
inet 127.0.0.1 netmask 255.0.0.0
inet6 ::1 prefixlen 128 scopeid 0x10<host>
loop txqueuelen 1000 (Boucle locale)
RX packets 768 bytes 59688 (58.2 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 768 bytes 59688 (58.2 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0

vmnet1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 192.168.153.1 netmask 255.255.255.0 broadcast 192.168.153.255
inet6 fe80::250:56ff:fec0:1 prefixlen 64 scopeid 0x20<link>
ether 00:50:56:c0:00:01 txqueuelen 1000 (Ethernet)
RX packets 0 bytes 0 (0.0 B)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 228 bytes 0 (0.0 B)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0

vmnet8: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 172.16.133.1 netmask 255.255.255.0 broadcast 172.16.133.255
inet6 fe80::250:56ff:fec0:8 prefixlen 64 scopeid 0x20<link>
ether 00:50:56:c0:00:08 txqueuelen 1000 (Ethernet)
RX packets 0 bytes 0 (0.0 B)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 230 bytes 0 (0.0 B)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0

wlp3s0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 132.227.184.17 netmask 255.255.255.0 broadcast 132.227.184.255
inet6 fe80::a26a:c5d2:23d0:43f2 prefixlen 64 scopeid 0x20<link>
inet6 2001:660:3302:28b8:c414:9666:9b86:ff46 prefixlen 64 scopeid 0x0<global>
ether 60:36:dd:ae:55:51 txqueuelen 1000 (Ethernet)
RX packets 40127 bytes 36164592 (34.4 MiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 13719 bytes 2401827 (2.2 MiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0

Here is the output of the lshw command :

Quote:

~$ sudo lshw -C network
*-network
description: Interface réseau sans fil
produit: Centrino Wireless-N 2230
fabriquant: Intel Corporation
identifiant matériel: 0
information bus: pci@0000:03:00.0
nom logique: wlp3s0
version: c4
numéro de série: 60:36:dd:ae:55:51
bits: 64 bits
horloge: 33MHz
fonctionnalités: pm msi pciexpress bus_master cap_list ethernet physical wireless
configuration: broadcast=yes driver=iwlwifi driverversion=4.15.0-0.bpo.2-amd64 firmware=18.168.6.1 ip=132.227.184.17 latency=0 link=yes multicast=yes wireless=IEEE 802.11
ressources: irq:27 mémoire:f7900000-f7901fff
*-network
description: Ethernet interface
produit: AR8161 Gigabit Ethernet
fabriquant: Qualcomm Atheros
identifiant matériel: 0
information bus: pci@0000:04:00.0
nom logique: enp4s0
version: 10
numéro de série: 50:46:5d:46:c2:ce
taille: 1Gbit/s
capacité: 1Gbit/s
bits: 64 bits
horloge: 33MHz
fonctionnalités: pm pciexpress msi msix bus_master cap_list ethernet physical tp 10bt 10bt-fd 100bt 100bt-fd 1000bt-fd autonegotiation
configuration: autonegotiation=on broadcast=yes driver=alx duplex=full latency=0 link=yes multicast=yes port=twisted pair speed=1Gbit/s
ressources: irq:19 mémoire:f7800000-f783ffff portE/S:d000(taille=128)

The content of /etc/network/interfaces :

Quote:

$ cat /etc/network/interfaces
# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).

source /etc/network/interfaces.d/*

# The loopback network interface
auto lo
iface lo inet loopback

#auto enp4s0
#allow-hotplug enp4s0
#iface enp4s0 inet dhcp

The content of /etc/NetworkManager/NetworkManager.conf :

Quote:

$ cat /etc/NetworkManager/NetworkManager.conf
[main]
plugins=ifupdown,keyfile

[ifupdown]
managed=false

I tried to add in the /etc/network/interfaces file those lines :

auto enp4s0
allow-hotplug enp4s0
iface enp4s0 inet dhcp

and enable in /etc/NetworkManager/NetworkManager.conf file the "managed" field but still not working. (Of course I restarted the services).

I also tried "sudo dhclient -v enp4s0", here is the output :

Quote:

$ sudo dhclient -v enp4s0
Internet Systems Consortium DHCP Client 4.3.5
Copyright 2004-2016 Internet Systems Consortium.
All rights reserved.
For info, please visit https://www.isc.org/software/dhcp/

Listening on LPF/enp4s0/50:46:5d:46:c2:ce
Sending on LPF/enp4s0/50:46:5d:46:c2:ce
Sending on Socket/fallback
DHCPDISCOVER on enp4s0 to 255.255.255.255 port 67 interval 6
DHCPDISCOVER on enp4s0 to 255.255.255.255 port 67 interval 9
DHCPDISCOVER on enp4s0 to 255.255.255.255 port 67 interval 8
DHCPDISCOVER on enp4s0 to 255.255.255.255 port 67 interval 14
DHCPDISCOVER on enp4s0 to 255.255.255.255 port 67 interval 17
DHCPDISCOVER on enp4s0 to 255.255.255.255 port 67 interval 7
No DHCPOFFERS received.
No working leases in persistent database - sleeping.

I also noticed on the output of ifconfig a new line :

Quote:

enp4s0:avahi: flags=4099<UP,BROADCAST,MULTICAST> mtu 1500
inet 169.254.9.225 netmask 255.255.0.0 broadcast 169.254.255.255
ether 50:46:5d:46:c2:ce txqueuelen 1000 (Ethernet)
device interrupt 19

Version of network-manager :

Quote:

~$ dpkg -s network-manager | grep '^Version:'
Version: 1.6.2-3

It seems that the DHCP server is not able to give me an IP address.

Here is the output of lspci :

Quote:

~$ lspci
00:00.0 Host bridge: Intel Corporation 3rd Gen Core processor DRAM Controller (rev 09)
00:01.0 PCI bridge: Intel Corporation Xeon E3-1200 v2/3rd Gen Core processor PCI Express Root Port (rev 09)
00:02.0 VGA compatible controller: Intel Corporation 3rd Gen Core processor Graphics Controller (rev 09)
00:14.0 USB controller: Intel Corporation 7 Series/C210 Series Chipset Family USB xHCI Host Controller (rev 04)
00:16.0 Communication controller: Intel Corporation 7 Series/C216 Chipset Family MEI Controller #1 (rev 04)
00:1a.0 USB controller: Intel Corporation 7 Series/C216 Chipset Family USB Enhanced Host Controller #2 (rev 04)
00:1b.0 Audio device: Intel Corporation 7 Series/C216 Chipset Family High Definition Audio Controller (rev 04)
00:1c.0 PCI bridge: Intel Corporation 7 Series/C216 Chipset Family PCI Express Root Port 1 (rev c4)
00:1c.1 PCI bridge: Intel Corporation 7 Series/C210 Series Chipset Family PCI Express Root Port 2 (rev c4)
00:1c.3 PCI bridge: Intel Corporation 7 Series/C216 Chipset Family PCI Express Root Port 4 (rev c4)
00:1d.0 USB controller: Intel Corporation 7 Series/C216 Chipset Family USB Enhanced Host Controller #1 (rev 04)
00:1f.0 ISA bridge: Intel Corporation HM76 Express Chipset LPC Controller (rev 04)
00:1f.2 SATA controller: Intel Corporation 7 Series Chipset Family 6-port SATA Controller [AHCI mode] (rev 04)
00:1f.3 SMBus: Intel Corporation 7 Series/C216 Chipset Family SMBus Controller (rev 04)
01:00.0 VGA compatible controller: NVIDIA Corporation GK107M [GeForce GT 650M] (rev a1)
03:00.0 Network controller: Intel Corporation Centrino Wireless-N 2230 (rev c4)
04:00.0 Ethernet controller: Qualcomm Atheros AR8161 Gigabit Ethernet (rev 10)

I don't have a dhcpd service running (because I saw some cases where there is a conflict between NetworkManager and DHCPD)

Please help!

nini09 · 11-12-2018, 03:40 PM

You can configure a static IP address to see what happen.

ondoho · 11-13-2018, 02:06 AM

too much information can be detrimental; it makes people tire and skip over your thread.
at least that's what i almost did...

my guess is it's a hardware driver problem.
please look at these searches and see if they apply to your situation.

you might also want to show us the output of

Code:

lspci -k | grep -A5 Ethernet

Skipper3121 · 11-13-2018, 08:02 AM

Hello,

Sorry for the long post.

Here is the out put of "lspci -k | grep -A5 Ethernet":

Quote:

~$ lspci -k | grep -A5 Ethernet
04:00.0 Ethernet controller: Qualcomm Atheros AR8161 Gigabit Ethernet (rev 10)
Subsystem: ASUSTeK Computer Inc. N56VZ
Kernel driver in use: alx
Kernel modules: alx

frankbell · 11-13-2018, 09:13 PM

Easy things first: try a known-good ethernet cable and a different port on the router/hub/switch. Stuff wears out.

Also, boot to a Live CD of something else and test the ethernet connection with it.

Those two tests will help you narrow the list of culprits.

ondoho · 11-14-2018, 01:10 PM

Code:

alx

is your driver module. it seems to be part of the kernel and not require any firmware.

try

Code:

dmesg|grep alx

to get a better picture of what is going on.

it could be a regression with the backported kernel - have you tried the vanilla kernel?
why do you use the bpo kernel?

Skipper3121 · 11-15-2018, 04:23 AM

Problem solved.

Like frankbell said, I tried a different port and it worked. The weird thing is that it stopped working after an update, this is why I thought it has something to do with it.

Rule N°1: always try easy things first.

Thank you all for the support.

ondoho · 11-16-2018, 12:54 PM

Quote:

Originally Posted by Skipper3121

The weird thing is that it stopped working after an update, this is why I thought it has something to do with it.

something like this has happened to me so many times!
imo it can't be sheer coincidence; there's usually some connection; maybe a scenario like this: i had a big cleanup day, and while in the midst of that i decided to also "clean up" (upgrade) my system. then i finished my cleanup, and moved the computer a little, pulling the cable a little, and the flaky connection gave up the ghost...
problem is, as a linux user one never thinks of a connection like that. always looking inside the system first.
one should write a treatise on linux user psychology.