[SOLVED] Recently I cannot get a connection through Ethernet

l3ullseye · 2022-04-11 09:20:41

Lately I cannot get a connection through Ethernet, WiFi connection to the same router it's OK. When I connect the Ethernet cable to my laptop nothing happens, no link light or anything like no cable is connected, I have switched the cable and ports, even tested them with a different machine with no problem at all. I didn't notice the exact moment it started since the WiFi works, so I just one day realized it was connected through WiFi and no Ethernet.

$ ip link
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: eno1: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc fq_codel state DOWN mode DEFAULT group default qlen 1000
    link/ether 70:5a:0f:18:43:9b brd ff:ff:ff:ff:ff:ff
    altname enp3s0
3: wlo1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP mode DORMANT group default qlen 1000
    link/ether 48:e2:44:d8:dc:7f brd ff:ff:ff:ff:ff:ff
    altname wlp2s0

$ lspci -nn
00:00.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 16h (Models 30h-3fh) Processor Root Complex [1022:1566]
00:01.0 VGA compatible controller [0300]: Advanced Micro Devices, Inc. [AMD/ATI] Mullins [Radeon R4/R5 Graphics] [1002:9851]
00:01.1 Audio device [0403]: Advanced Micro Devices, Inc. [AMD/ATI] Kabini HDMI/DP Audio [1002:9840]
00:02.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 16h (Models 30h-3fh) Host Bridge [1022:156b]
00:02.1 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Family 16h Processor Functions 5:1 [1022:1439]
00:02.2 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Family 16h Processor Functions 5:1 [1022:1439]
00:02.3 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Family 16h Processor Functions 5:1 [1022:1439]
00:02.5 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Family 16h Processor Functions 5:1 [1022:1439]
00:08.0 Encryption controller [1080]: Advanced Micro Devices, Inc. [AMD] Kabini/Mullins PSP-Platform Security Processor [1022:1537]
00:10.0 USB controller [0c03]: Advanced Micro Devices, Inc. [AMD] FCH USB XHCI Controller [1022:7814] (rev 11)
00:11.0 SATA controller [0106]: Advanced Micro Devices, Inc. [AMD] FCH SATA Controller [AHCI mode] [1022:7804] (rev 39)
00:12.0 USB controller [0c03]: Advanced Micro Devices, Inc. [AMD] FCH USB EHCI Controller [1022:7808] (rev 39)
00:13.0 USB controller [0c03]: Advanced Micro Devices, Inc. [AMD] FCH USB EHCI Controller [1022:7808] (rev 39)
00:14.0 SMBus [0c05]: Advanced Micro Devices, Inc. [AMD] FCH SMBus Controller [1022:780b] (rev 42)
00:14.2 Audio device [0403]: Advanced Micro Devices, Inc. [AMD] FCH Azalia Controller [1022:780d] (rev 02)
00:14.3 ISA bridge [0601]: Advanced Micro Devices, Inc. [AMD] FCH LPC Bridge [1022:780e] (rev 11)
00:18.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 16h (Models 30h-3fh) Processor Function 0 [1022:1580]
00:18.1 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 16h (Models 30h-3fh) Processor Function 1 [1022:1581]
00:18.2 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 16h (Models 30h-3fh) Processor Function 2 [1022:1582]
00:18.3 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 16h (Models 30h-3fh) Processor Function 3 [1022:1583]
00:18.4 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 16h (Models 30h-3fh) Processor Function 4 [1022:1584]
00:18.5 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Family 16h (Models 30h-3fh) Processor Function 5 [1022:1585]
02:00.0 Network controller [0280]: Broadcom Inc. and subsidiaries BCM43142 802.11b/g/n [14e4:4365] (rev 01)
03:00.0 Ethernet controller [0200]: Realtek Semiconductor Co., Ltd. RTL810xE PCI Express Fast Ethernet controller [10ec:8136] (rev 07)
04:00.0 Unassigned class [ff00]: Realtek Semiconductor Co., Ltd. RTS5229 PCI Express Card Reader [10ec:5229] (rev 01)

# dmesg | grep r8169
[    6.309242] r8169 0000:03:00.0 eth0: RTL8106e, 70:5a:0f:18:43:9b, XID 449, IRQ 43
[    7.485184] r8169 0000:03:00.0 eno1: renamed from eth0
[    8.904905] RTL8208 Fast Ethernet r8169-0-300:00: attached PHY driver (mii_bus:phy_addr=r8169-0-300:00, irq=MAC)
[    9.521650] r8169 0000:03:00.0 eno1: Link is Down

$ systemctl list-unit-files --state=enabled
UNIT FILE                          STATE   VENDOR PRESET
cups.path                          enabled disabled     
cups.service                       enabled disabled     
getty@.service                     enabled enabled      
lightdm.service                    enabled disabled     
NetworkManager-dispatcher.service  enabled disabled     
NetworkManager-wait-online.service enabled disabled     
NetworkManager.service             enabled disabled     
numlockon.service                  enabled disabled     
cups.socket                        enabled disabled     
remote-fs.target                   enabled enabled      

10 unit files listed.

Thanks in advance

Last edited by l3ullseye (2022-04-13 20:26:24)

ewaller · 2022-04-11 14:14:29

Replace the cable. Again. (Cables are the bane of my existence.)

If you plug the cable from your router into another computer, does it work?
If you connect your computer to another network using a cable, does it work?

Did I mention, try another cable?
Is it your router? Have you rebooted it? Do any link lights light on either the computer or the router?
What happens if you boot from the install media and try to connect?

Edit: Oh, Welcome to the Arch Linux forums.

Last edited by ewaller (2022-04-11 14:15:20)

l3ullseye · 2022-04-12 03:28:21

ewaller wrote:

Replace the cable. Again. (Cables are the bane of my existence.)

I have, several times...

ewaller wrote:

If you plug the cable from your router into another computer, does it work?

Yes it does...

ewaller wrote:

If you connect your computer to another network using a cable, does it work?

Yes it does, it appears as the problem is just at my home network...

ewaller wrote:

Is it your router? Have you rebooted it? Do any link lights light on either the computer or the router?

I have rebooted and reset it I even change the router, same thing...

ewaller wrote:

What happens if you boot from the install media and try to connect?

It does not work, but I have tested this with another network and it works, with both the installed system and with the install media...

ewaller wrote:

Oh, Welcome to the Arch Linux forums.

Thanks :)

It's really weird that I have Ethernet issues only at my home network with just this laptop :/

At some point it looks like its trying to connect...

# dmesg | grep eno1
[    6.872675] r8169 0000:03:00.0 eno1: renamed from eth0
[    8.909851] r8169 0000:03:00.0 eno1: Link is Down
[   10.319291] r8169 0000:03:00.0 eno1: Link is Up - 100Mbps/Full - flow control rx/tx
[   10.319329] IPv6: ADDRCONF(NETDEV_CHANGE): eno1: link becomes ready
[   10.842597] r8169 0000:03:00.0 eno1: Link is Down
[   12.437389] r8169 0000:03:00.0 eno1: Link is Up - 100Mbps/Full - flow control rx/tx
[   13.216365] r8169 0000:03:00.0 eno1: Link is Down
[   14.849270] r8169 0000:03:00.0 eno1: Link is Up - 100Mbps/Full - flow control rx/tx
[   15.638798] r8169 0000:03:00.0 eno1: Link is Down
[   17.292439] r8169 0000:03:00.0 eno1: Link is Up - 100Mbps/Full - flow control rx/tx
[   18.065229] r8169 0000:03:00.0 eno1: Link is Down
[   19.714573] r8169 0000:03:00.0 eno1: Link is Up - 100Mbps/Full - flow control rx/tx
[   20.491798] r8169 0000:03:00.0 eno1: Link is Down
[   22.063362] r8169 0000:03:00.0 eno1: Link is Up - 100Mbps/Full - flow control rx/tx
[   22.838265] r8169 0000:03:00.0 eno1: Link is Down
[   24.527483] r8169 0000:03:00.0 eno1: Link is Up - 100Mbps/Full - flow control rx/tx
[   25.314038] r8169 0000:03:00.0 eno1: Link is Down
[   26.928685] r8169 0000:03:00.0 eno1: Link is Up - 100Mbps/Full - flow control rx/tx
...

$ ip link
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: eno1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP mode DEFAULT group default qlen 1000
    link/ether 70:5a:0f:18:43:9b brd ff:ff:ff:ff:ff:ff
    altname enp3s0
3: wlo1: <NO-CARRIER,BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state DORMANT mode DORMANT group default qlen 1000
    link/ether fe:ae:b4:a0:24:d0 brd ff:ff:ff:ff:ff:ff permaddr 48:e2:44:d8:dc:7f
    altname wlp2s0

seth · 2022-04-12 06:26:58

The initial "ip link" had no carrier on the eno1, why ewaller suspected the cable (since leaving aside rather strange kernel bugs, that's the absolutely most likely explanation)

Please post the complete system journal and output of

find /etc/systemd -type l -exec test -f {} \; -print | awk -F'/' '{ printf ("%-40s | %s\n", $(NF-0), $(NF-1)) }' | sort -f

l3ullseye · 2022-04-12 08:25:13

Yes sometimes ip link outputs no carrier on the eno1...

Sorry, the complete system journal output is around 50MB, should I compress and upload the file somewhere?

$ find /etc/systemd -type l -exec test -f {} \; -print | awk -F'/' '{ printf ("%-40s | %s\n", $(NF-0), $(NF-1)) }' | sort -f
cups.path                                | multi-user.target.wants
cups.service                             | multi-user.target.wants
cups.service                             | printers.target.wants
cups.socket                              | sockets.target.wants
dbus-org.freedesktop.nm-dispatcher.service | system
dirmngr.socket                           | sockets.target.wants
display-manager.service                  | system
gcr-ssh-agent.socket                     | sockets.target.wants
getty@tty1.service                       | getty.target.wants
gpg-agent-browser.socket                 | sockets.target.wants
gpg-agent-extra.socket                   | sockets.target.wants
gpg-agent-ssh.socket                     | sockets.target.wants
gpg-agent.socket                         | sockets.target.wants
NetworkManager-wait-online.service       | network-online.target.wants
NetworkManager.service                   | multi-user.target.wants
numlockon.service                        | multi-user.target.wants
p11-kit-server.socket                    | sockets.target.wants
pulseaudio.socket                        | sockets.target.wants
remote-fs.target                         | multi-user.target.wants
xdg-user-dirs-update.service             | default.target.wants

Thanks!

seth · 2022-04-12 08:44:37

The journal of one problematic boot will do,

sudo journalctl -b | curl -F 'file=@-' 0x0.st

for the present one.

l3ullseye · 2022-04-12 09:16:13

OK here are the logs, I uploaded both

Full system jounal

Boot journal

Thanks

seth · 2022-04-12 13:14:26

The carrier reconnects every few (2-5) seconds.
Cable.
Plugs.
Cable.
Jack?
Cable.
On a stretch you lack linux-firmware or there's a parallel windows installation in hibernation (3rd link below)
But it's more likely the cable.
You could also test the behavior on some live distro.
But it's the cable.
Or the NIC is fried.
But then it's more likely the cable.

l3ullseye · 2022-04-12 20:23:58

I don't have a parallel windows installation, just linux.

I have tested with live distros, manjaro, ubuntu, slax, all the same.

Don't think the NIC is fried, it works on a different network.

It's a weird combination between my laptop and my home network because other computers connect without problems

I'll recheck the cables and router some more, thanks for the help!

seth · 2022-04-12 20:28:51

Don't think the NIC is fried, it works on a different network.

Compare

ethtool eno1

on good and bad networks (because the carrier is so unstable, you might have to try a couple of times - look out for the "Link partner" information)

I could imagine that the bad connection agrees on a higher standard - but the cable doesn't agree with that…

l3ullseye · 2022-04-13 20:23:22

I recheck the cables with the help of a different laptop, and all of them worked, so I decided to take all the cables to another network and test them with mi laptop and it turn out that none of them worked, finally I grabbed a new cable and tested at my home network and I have an Ethernet connection while typing this post.

It was hard to believe that all the cables worked with another laptop and not mine, it seems that the NIC of my laptop is more demanding than the one in the other laptop

Sorry for the inconvenience, and thanks for all the help ewaller and seth you where right in the first place.

ewaller · 2022-04-13 21:44:14

Glad you got it sorted.

NICs can operate at 10, 100 and sometimes 1000 Mb, Most of the time things are set to auto-negotiate. 10 Mb and 100 Mb both require 2 pairs of signals (generally) 1000 Mb requires 4 pairs (generally). 100 uses multi level encoding. 10 Mb doesn't. It could be your NICs end up negotiating different rates. Any chance the one that works is connecting at10 Mb ?

With multilevel encoding, cable equalization is important. Perhaps the NIC that works with those cables has a greater equalization range and can pull signals out of the mud. Or there is an pair where one side is open and one NIC is able to work on a half pair and a ground loop somewhere. This should not work, but I've seen it happen -- Ethernet is pretty darn robust.

Or, perhaps the one that does not work is trying to negotiate to 1000 Mb, but the cables don't have four pair or are not up to the task, but the other NIC connects at 100 Mb and does not even care of the extra 2 pair exist.

I hate cables.

l3ullseye · 2022-04-13 21:58:15

ewaller wrote:

Any chance the one that works is connecting at10 Mb ?

No, it's connecting at 100 Mb.

And yes, now I hate cables too.

Arch Linux

#1 2022-04-11 09:20:41

[SOLVED] Recently I cannot get a connection through Ethernet

#2 2022-04-11 14:14:29

Re: [SOLVED] Recently I cannot get a connection through Ethernet

#3 2022-04-12 03:28:21

Re: [SOLVED] Recently I cannot get a connection through Ethernet

#4 2022-04-12 06:26:58

Re: [SOLVED] Recently I cannot get a connection through Ethernet

#5 2022-04-12 08:25:13

Re: [SOLVED] Recently I cannot get a connection through Ethernet

#6 2022-04-12 08:44:37

Re: [SOLVED] Recently I cannot get a connection through Ethernet

#7 2022-04-12 09:16:13

Re: [SOLVED] Recently I cannot get a connection through Ethernet

#8 2022-04-12 13:14:26

Re: [SOLVED] Recently I cannot get a connection through Ethernet

#9 2022-04-12 20:23:58

Re: [SOLVED] Recently I cannot get a connection through Ethernet

#10 2022-04-12 20:28:51

Re: [SOLVED] Recently I cannot get a connection through Ethernet

#11 2022-04-13 20:23:22

Re: [SOLVED] Recently I cannot get a connection through Ethernet

#12 2022-04-13 21:44:14

Re: [SOLVED] Recently I cannot get a connection through Ethernet

#13 2022-04-13 21:58:15

Re: [SOLVED] Recently I cannot get a connection through Ethernet

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