---
title: Howto Ethtool
categories: sysadmin network
...

* Manpage : <https://manpages.debian.org/stretch/ethtool/ethtool.8.en.html>

ethtool est un outil permettant de voir et contrôler les paramètres d'une carte réseau.

## Installation


~~~
# apt install ethtool

# ethtool --version
ethtool version 4.8
~~~

## Utilisation

### Consulter l'état d'une interface

~~~
# ethtool eth0
Settings for eth0:
	Supported ports: [ TP MII ]
	Supported link modes:   10baseT/Half 10baseT/Full 
	                        100baseT/Half 100baseT/Full 
	                        1000baseT/Half 1000baseT/Full 
	Supported pause frame use: No
	Supports auto-negotiation: Yes
	Advertised link modes:  10baseT/Half 10baseT/Full 
	                        100baseT/Half 100baseT/Full 
	                        1000baseT/Half 1000baseT/Full 
	Advertised pause frame use: Symmetric Receive-only
	Advertised auto-negotiation: Yes
	Link partner advertised link modes:  10baseT/Half 10baseT/Full 
	                                     100baseT/Half 100baseT/Full 
	Link partner advertised pause frame use: Symmetric
	Link partner advertised auto-negotiation: Yes
	Speed: 100Mb/s
	Duplex: Full
	Port: MII
	PHYAD: 0
	Transceiver: internal
	Auto-negotiation: on
	Supports Wake-on: pumbg
	Wake-on: g
	Current message level: 0x00000033 (51)
			       drv probe ifdown ifup
	Link detected: yes
~~~

### Changer son état

Par exemple, configurer la vitesse à 10Mb/s, le duplex half, et désactiver l'auto-négotiation :

~~~
# ethtool -s eth0 speed 10 duplex half autoneg off
~~~

Pour changer l'adresse mac :

~~~
# ethtool -s eth0 phyad 01:23:45:67:89:0a
~~~