Ethtool

ethtool is a Linux command for displaying or modifying the Network Interface Controller (NIC) parameters.

Usage

The command is useful for:

• Identification and diagnosis of Ethernet devices
• Extended Ethernet devices statistics
• Control speed, duplex, auto-negotiation and flow control for Ethernet devices
• Control checksum offload and other hardware offload features
• Control digital media adapter (DMA) ring sizes and interrupt moderation
• Control receive queue selection for multi-queue devices
• Upgrade firmware in flash memory

Example

• Display the current parameters for your eth0 device:

$ ethtool eth0
Settings for eth0:
	Supported ports: [ TP ]
	Supported link modes:   10baseT/Half 10baseT/Full 
	                        100baseT/Half 100baseT/Full 
	                        1000baseT/Full 
	Supported pause frame use: No
	Supports auto-negotiation: Yes
	Advertised link modes:  10baseT/Half 10baseT/Full 
	                        100baseT/Half 100baseT/Full 
	                        1000baseT/Full 
	Advertised pause frame use: No
	Advertised auto-negotiation: Yes
	Speed: 1000Mb/s
	Duplex: Full
	Port: Twisted Pair
	PHYAD: 2
	Transceiver: internal
	Auto-negotiation: on
	MDI-X: on
Cannot get wake-on-lan settings: Operation not permitted
	Current message level: 0x00000007 (7)
			       drv probe link
	Link detected: yes

• Display Ethernet driver settings:

$ ethtool -i eth0
driver: e1000e
version: 2.1.4-k
firmware-version: 0.13-3
bus-info: 0000:00:19.0
supports-statistics: yes
supports-test: yes
supports-eeprom-access: yes
supports-register-dump: yes
supports-priv-flags: no

• Make your NIC blink for the physical port using eth0:

$ ethtool -p eth0

This is useful if your ethernet adapter has multiple ports and you are not sure which one has been assigned to eth0.

See also

• tcpdump

List of utilities in the "net-tools" project

• arp
• hostname
• ifconfig
• netstat
• rarp
• route
• plipconfig
• slattach
• mii-tool — a CLI command allowing to modify the Network Interface Controller (NIC) parameters.
• iptunnel
• ipmaddr

References

• Official website
• Ethtool examples