Table of Contents

Linux Commands#network

ethtool : How to use ethtool command in Linux with examples

ethtool - Display or change ethernet card settings



man ethtool

       ethtool -s devname [speed N] [duplex half|full] [port tp|aui|bnc|mii] [mdix auto|on|off] [autoneg on|off]
              [advertise N] [phyad N] [xcvr internal|external] [wol p|u|m|b|a|g|s|d...]  [sopass xx:yy:zz:aa:bb:cc]
              [msglvl N | msglvl type on|off ...]

       -i --driver
              queries the specified ethernet device for associated driver information.

       -k --show-offload
              queries the specified ethernet device for offload information.


Example

Check

# ethtool eth3
Settings for eth3:
        Supported ports: [ FIBRE ]
        Supported link modes:   1000baseT/Half 1000baseT/Full
        Supports auto-negotiation: Yes
        Advertised link modes:  1000baseT/Half 1000baseT/Full
        Advertised auto-negotiation: Yes
        Speed: 1000Mb/s
        Duplex: Full
        Port: FIBRE
        PHYAD: 1
        Transceiver: internal
        Auto-negotiation: on
        Supports Wake-on: g
        Wake-on: g
        Current message level: 0x000000ff (255)
        Link detected: yes


-s --change

       ethtool -s devname [speed N] [duplex half|full] [port tp|aui|bnc|mii] [mdix auto|on|off] [autoneg on|off]
              [advertise N] [phyad N] [xcvr internal|external] [wol p|u|m|b|a|g|s|d...]  [sopass xx:yy:zz:aa:bb:cc]
              [msglvl N | msglvl type on|off ...]
ethtool -s eth0 speed 100 duplex full autoneg off
ethtool -s eth0 autoneg on


-i --driver

       -i --driver
              Queries the specified network device for associated driver information.
# ethtool -i eth3
driver: tg3
version: 3.119
firmware-version: 5715s-v3.28
bus-info: 0000:07:04.1


show-offload

       -k --show-features --show-offload
              Queries the specified network device for the state of protocol offload and other features.
# ethtool -k eth3
Offload parameters for eth3:
Cannot get device udp large send offload settings: Operation not supported
rx-checksumming: on
tx-checksumming: on
scatter-gather: on
tcp segmentation offload: on
udp fragmentation offload: off
generic segmentation offload: off
generic-receive-offload: off