{Solved} Ethernet not recognised!

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jbh911
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{Solved} Ethernet not recognised!

Post by jbh911 » Tue Dec 20, 2016 9:37 pm

I've changed modems and 3 of 4 mc connected to the internet via ethernet without any problems, but the 4th, a ASUS K52F Series laptop won't.
Message is cable disconnected. I'm running Linux Mint 18 Mate
I've confirmed the connection with other mcs and all work fine.
Help would most appreciated
$ ifconfig
ens5f5 Link encap:Ethernet HWaddr 20:cf:30:16:a5:04
UP BROADCAST MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:0 (0.0 B) TX bytes:0 (0.0 B)
Interrupt:32

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:65536 Metric:1
RX packets:561 errors:0 dropped:0 overruns:0 frame:0
TX packets:561 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1
RX bytes:65317 (65.3 KB) TX bytes:65317 (65.3 KB)

wls1 Link encap:Ethernet HWaddr 74:f0:6d:3c:80:bf
inet addr:192.168.20.2 Bcast:192.168.20.255 Mask:255.255.255.0
inet6 addr: fe80::e2ed:639f:a2ff:31f7/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1https://www.linuxmint.com/start/serena/
RX packets:88179 errors:0 dropped:0 overruns:0 frame:0https://www.linuxmint.com/start/serena/
TX packets:49502 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:122091095 (122.0 MB) TX bytes:4959779 (4.9 MB)
Last edited by jbh911 on Sun Dec 03, 2017 2:55 am, edited 1 time in total.

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amethyst_igor
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Re: Ethernet not recognised!

Post by amethyst_igor » Mon Dec 26, 2016 11:34 am

I suggest approaching the problem as a hardware issue. Ethernet port may be bad, cable may be bad, or router. Connect a USB-to-Ethernet adapter to the laptop and try to get connected that way, bypassing the built-in ethernet port. Sometimes those ports go bad due to age and abuse.
I run both Windows 10 and Linux Mint 18 in dual boot with two SSDs and have other rigs running various versions of Linux. My blog.

jbh911
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Re: Ethernet not recognised!

Post by jbh911 » Mon Dec 26, 2016 8:09 pm

Thanks for the response amethyst_igor. I doubt it's a physical issue as the laptop has not been abused or had a lot of use and I don't have the item you referred to. To be honest didn't know they existed!
The key to me is the missing inet address.
I can re-establish the inet add: with following
$ sudo ifconfig ens5f5 192.168.20.10 netmask 255.255.255.0
$ ifconfig
I get the message "Connection established" - that's with WiFi OFF. Cursor over Ethernet icon generates the message "Connected to wired network"
However there is no functional wired connection, ie no access to the web.
Now route shows there is no Default Gateway for ens5f5
$ sudo route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
link-local * 255.255.0.0 U 1000 0 0 ens5f5
192.168.20.0 * 255.255.255.0 U 0 0 0 ens5f5
A check of the default gateway on the other mcs gives the same result: NF17ACV.Home, which not what I expected, not in that form anyway.
A check of /etc/resolv.conf on other mcs and this one ens5f5: gives
nameserver 127.0,1,1
search Home
When I try to install that default gateway into ens5f5 - with sudo route add default gw NF17AVC.Home
I get NF17AVC.Home: Unknown host
What of this odd gateway address- and Eth address :?:
Is there a way to establish the ethernet connection automatically from within Terminal?

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amethyst_igor
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Re: Ethernet not recognised!

Post by amethyst_igor » Tue Dec 27, 2016 11:18 pm

jbh911 wrote:Thanks for the response amethyst_igor. I doubt it's a physical issue as the laptop has not been abused or had a lot of use and I don't have the item you referred to. To be honest didn't know they existed!
The key to me is the missing inet address.
I can re-establish the inet add: with following
$ sudo ifconfig ens5f5 192.168.20.10 netmask 255.255.255.0
$ ifconfig
I get the message "Connection established" - that's with WiFi OFF. Cursor over Ethernet icon generates the message "Connected to wired network"
However there is no functional wired connection, ie no access to the web.
Now route shows there is no Default Gateway for ens5f5
$ sudo route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
link-local * 255.255.0.0 U 1000 0 0 ens5f5
192.168.20.0 * 255.255.255.0 U 0 0 0 ens5f5
A check of the default gateway on the other mcs gives the same result: NF17ACV.Home, which not what I expected, not in that form anyway.
A check of /etc/resolv.conf on other mcs and this one ens5f5: gives
nameserver 127.0,1,1
search Home
When I try to install that default gateway into ens5f5 - with sudo route add default gw NF17AVC.Home
I get NF17AVC.Home: Unknown host
What of this odd gateway address- and Eth address :?:
Is there a way to establish the ethernet connection automatically from within Terminal?
Those USB-to-Ethernet gadgets are cheap and are really helpful in a day when many laptops forego having an ethernet port altogether, to my chagrin. The techno-elite all a-sudden decided cables are over. Macbooks, Chromebooks, even Windows laptops nowadays lack an Ethernet port. Well, smart phones started it.

I'd check your router and see what devices are connected and what IP addresses they are using. Your laptop only tells half the story. I'd try connecting to different ports on the same router, swap out the cable, try connecting in Windows or another Linux distro.
I run both Windows 10 and Linux Mint 18 in dual boot with two SSDs and have other rigs running various versions of Linux. My blog.

jbh911
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Re: Ethernet not recognised!

Post by jbh911 » Wed Dec 28, 2016 2:54 am

by amethyst_igor » Wed Dec 28, 2016 2:18 pm

I'd check your router and see what devices are connected and what IP addresses they are using. Your laptop only tells half the story. I'd try connecting to different ports on the same router, swap out the cable, try connecting in Windows or another Linux distro.
Have used other mcs from same location without an issue! Only have LM 18 Cinnamon on the problem laptop but can boot it from a live USB, I'll try that. Oops that's LVM installation on the problem laptop! Ethernet not detected during LM 18 Mate install into RAM!

I do have a fall back position, restore the image which includes W7 or W10. I'll go that way to sort out if it's a connector of software issue. :D

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