LAN connection not established under certain circumstances

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Friedrich79
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Posts: 7
Joined: Wed Feb 05, 2014 9:35 am

LAN connection not established under certain circumstances

Postby Friedrich79 » Sat May 27, 2017 6:12 pm

Sorry for the vague topic, but this is what I observe on my notebook running Linux Mint 18 (inxi output below).

1. Whenever I use a certain LAN cable, Linux Mint behaves like there is no cable at all. Also the LED on my router -- otherwise indicating a connection -- remains off.
When I use the same cable with my (dual-boot) Windows 10, however, it works just fine. How is that possible and how could I diagnose this further?

2. Other cables work with Linux Mint. However, when I repeatedly unplug and re-plug the cable (always waiting after unplug/re-plug for the connection to be disconnected/re-established), the connection will not be re-established again after disconnecting two times. The "Tray Icon" just keeps showing that there is no ethernet connection. But the LED on my router lights up, showing that there is some kind of connection... How could I diagnose this further? (Under Windows 10, I can unplug and re-plug the cable as often as I want. So I guess it is no router issue.)

Thanks for any help!

Code: Select all

System:    Host: linus-laptop Kernel: 4.4.0-47-generic x86_64 (64 bit gcc: 5.4.0)
           Desktop: MATE 1.14.1 (Gtk 3.18.9-1ubuntu3.3)
           Distro: Linux Mint 18 Sarah
Machine:   System: Notebook (portable) product: P65_P67RGRERA
           Mobo: Notebook model: P65_P67RGRERA
           Bios: American Megatrends v: 1.05.18 date: 07/29/2016
CPU:       Quad core Intel Core i7-6820HK (-HT-MCP-) cache: 8192 KB
           flags: (lm nx sse sse2 sse3 sse4_1 sse4_2 ssse3 vmx) bmips: 21695
           clock speeds: max: 3600 MHz 1: 2828 MHz 2: 799 MHz 3: 799 MHz
           4: 912 MHz 5: 799 MHz 6: 2450 MHz 7: 3300 MHz 8: 799 MHz
Graphics:  Card: NVIDIA GM204M [GeForce GTX 970M] bus-ID: 01:00.0
           Display Server: X.Org 1.18.4 driver: nvidia
           Resolution: 1920x1080@60.02hz
           GLX Renderer: GeForce GTX 970M/PCIe/SSE2
           GLX Version: 4.5.0 NVIDIA 375.66 Direct Rendering: Yes
Audio:     Card-1 NVIDIA GM204 High Definition Audio Controller
           driver: snd_hda_intel bus-ID: 01:00.1
           Card-2 Intel Sunrise Point-H HD Audio
           driver: snd_hda_intel bus-ID: 00:1f.3
           Sound: Advanced Linux Sound Architecture v: k4.4.0-47-generic
Network:   Card-1: Realtek RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller
           driver: r8169 v: 2.3LK-NAPI port: d000 bus-ID: 02:00.1
           IF: enp2s0f1 state: up speed: 1000 Mbps duplex: full mac: <filter>
           Card-2: Intel Wireless 8260 driver: iwlwifi bus-ID: 03:00.0
           IF: wlp3s0 state: down mac: <filter>
Drives:    HDD Total Size: 512.1GB (2.6% used)
           ID-1: /dev/sda model: Samsung_SSD_850 size: 512.1GB
Partition: ID-1: / size: 54G used: 8.0G (16%) fs: ext4 dev: /dev/sda6
           ID-2: swap-1 size: 2.00GB used: 0.00GB (0%) fs: swap dev: /dev/sda7
RAID:      No RAID devices: /proc/mdstat, md_mod kernel module present
Sensors:   System Temperatures: cpu: 44.0C mobo: N/A gpu: 0.0:50C
           Fan Speeds (in rpm): cpu: N/A
Info:      Processes: 251 Uptime: 4 min Memory: 1011.6/32129.5MB
           Init: systemd runlevel: 5 Gcc sys: 5.4.0
           Client: Shell (bash 4.3.481) inxi: 2.2.35



deepakdeshp
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Joined: Sun Aug 09, 2015 10:00 am

Re: LAN connection not established under certain circumstances

Postby deepakdeshp » Sun May 28, 2017 7:16 am

Not an answer, buy you can set up wi fi network and eliminate the cable. This is assuming you have a wi fi router.
If I have helped you solve a problem, please add [SOLVED] to your first post title, it helps other users looking for help, and keeps the forum clean.
I am using Mint 18 Cinnamon 64 bit with AMD processor .

Friedrich79
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Posts: 7
Joined: Wed Feb 05, 2014 9:35 am

Re: LAN connection not established under certain circumstances

Postby Friedrich79 » Wed May 31, 2017 10:51 am

Thanks for the suggestion, but as you said yourself this is not really a solution.

I found the solution to part 1) of my problem, though: It turns out that I did a bad job crimping the cable plug. Only half of the 8 wires were connected. Interestingly, Windows 10 is not bothered by this and uses the functioning 4 wires to communicate. The Linux driver seems to be less forgiving here.

Part 2) of my problem still persists, but it does not really occur in everyday usage and I can always reboot to make it work gain.

Uranium
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Posts: 17
Joined: Wed Aug 19, 2015 9:27 pm

Re: LAN connection not established under certain circumstances

Postby Uranium » Mon Jul 03, 2017 12:56 pm

Seems like whenever there is a post of a pervasive and deep (i.e. Impossible to nail down) networking issues, that person is using a realtek chipset.


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