How to change Ethernet network card speed and duplex settings in ubuntu

This tutorial will explain how to change network card speed and duplex settings in ubuntu

Using ethtool

ethtool can be used to query and change settings such as speed, auto- negotiation and checksum offload on many network devices, especially Ethernet devices.

Install ethtool in ubuntu

sudo apt-get install ethtool

You can check the current Ethernet network card speed and duplex settings using the following command

sudo ethtool eth0

Where eth0 is the Ethernet network card interface

Turn off Auto-Negotiate feature using the following command

sudo ethtool -s eth0 autoneg off

ethtool Syntax

sudo ethtool -s eth0 speed [SPEED] duplex  [DUPLEX]

Example 1

This example will show you how to setup your ethernet network card speed 100 and full duplex

sudo ethtool -s eth0 speed 100 duplex full

Example 2

This example will show you how to setup your ethernet network card speed 10 and half duplex

sudo ethtool -s eth0 speed 10 duplex half