LKBEN11690: How to find the speed of your network interface on linux.

Symptom

You have different NICs (network interface cards) and need to find out the speed of the link.

Cause

This can be important for server systems

Solution

To find detailed information about the speed of the network interface, you can use the ethtool command.

sudo ethtool <INTERFACE>

Where <INTERFACE> is a placeholder for the interface you would like information about. In the output below, the interface is enp6s0f1 which is connected via fibre. The link speed is 10 GBit.

Here some output:

Settings for enp6s0f1:
        Supported ports: [ FIBRE ]
        Supported link modes:   1000baseT/Full
                                10000baseT/Full
        Supported pause frame use: Symmetric
        Supports auto-negotiation: No
        Supported FEC modes: Not reported
        Advertised link modes:  Not reported
        Advertised pause frame use: No
        Advertised auto-negotiation: No
        Advertised FEC modes: Not reported
        Speed: 10000Mb/s
        Duplex: Full
        Auto-negotiation: off
        Port: FIBRE
        PHYAD: 0
        Transceiver: internal
        Supports Wake-on: g
        Wake-on: d
        Current message level: 0x00002000 (8192)
                               hw
        Link detected: yes

Have fun.

Disclaimer:

The information provided in this document is intended for your information only. Lubby makes no claims to the validity of this information. Use of this information is at own risk!

About the Author

Author: Wim Peeters - Keskon GmbH & Co. KG

Wim Peeters is electronics engineer with an additional master in IT and over 30 years of experience, including time spent in support, development, consulting, training and database administration. Wim has worked with SQL Server since version 6.5. He has developed in C/C++, Java and C# on Windows and Linux. He writes knowledge base articles to solve IT problems and publishes them on the Lubby Knowledge Platform.

Latest update: 20/11/2023