Check or Set network interface to DHCP: Open file in a text editor as root:

sudo nano /etc/network/interfaces

Check the eth0 lines in the file:

auto eth0

iface eth0 inet dhcp

Save the file and exit.

Restart the network:

sudo service network-manager restart

DEFAULT settings for eth0 with dhcp:

# The loopback network interface
auto lo eth0
iface lo inet loopback

# The primary network interface
iface eth0 inet dhcp

Logman

Posted 2014-07-12T15:26:16.290

Reputation: 3 452

hey i changed it to "auto eth0 iface eth0 inet dhcp" and restarted it too... it was loopback instead of dhcp earlier but it still seems no different...btw i edited the original file...is there a way to reset to the default settings? – mrdoubtful – 2014-07-12T18:44:44.820

@mrdoubtful Added the default settings for the network interface. – Logman – 2014-07-12T19:28:10.163

I changed it to dhcp and restarted but i'm still disconnected. This is the /etc/network/interfaces file...

interfaces(5) file used by ifup(8) and ifdown(8)

auto lo iface lo inet dhcp – mrdoubtful – 2014-07-15T09:42:42.200

@mrdoubtful Can you post file above? everything in the /etc/network/interfaces file... – Logman – 2014-07-15T22:19:43.013

is that a typo in your comment? "auto lo iface lo inet dhcp" should be "auto lo eth0 iface eth0 inet dhcp". Everything I posted as default is everything you need if you have one network adapter. – Logman – 2014-07-15T22:22:47.200

Wel actually I left tat out...I have posted the file btw – mrdoubtful – 2014-07-20T13:55:45.970

you should have modified your original question and not added it as an answer which it is not. I moved the content. – Logman – 2014-07-20T14:38:15.103

Hope the screenshots help... – mrdoubtful – 2014-07-28T19:09:03.753

I had to edit /etc/NetworkManager/NetworkManager.conf and I've changed managed=false to managed=true – Wellington Lorindo – 2016-07-18T14:03:18.953

What does your "/etc/network/interfaces" have? is it dhcp? – Logman – 2014-07-12T15:40:08.577

Do you have a gui? What does Network Manager display? It should have an Auto eth0 line with Connect automatically and Available to everyone checkboxes. Display screen if you can. – Logman – 2014-07-20T14:43:29.550

Ubuntu 14.04 wired connection not detecting

Answers

interfaces(5) file used by ifup(8) and ifdown(8)