Ethtool
Updated: 11/13/2018 by Computer Hope
In Linux kernel-based operating systems, ethtool is a utility for viewing and modifying network interface card parameters and device drivers. The example below illustrates ethtool used to display the parameters for the primary NIC (network interface card).
$ ethtool eth0
The next command displays parameter information and display device driver information for the primary NIC:
$ ethtool -i eth0
The final command shown may can set the NIC speed in megabytes per second. This specific example sets the speed to 100 MB/s:
$ ethtool -s eth0 speed 100
For more information about ethtool, including options available on your system, run:
man ethtool
If ethtool is not installed on your system, use your package manager to install it. For example, on Debian or Ubuntu systems, use apt:
sudo apt update && sudo apt install ethtool