Ethtool
ethtool
[1] command is used to view and modify network device drivers setting, in particular wired Ethernet devices.
ethtool eno1
ethtool eth0
ethtool -i eno1
ethtool -i eth2 driver: eth2 version: 2.0 firmware-version: N/A bus-info: N/A
ethtool -S eno1 --statistics
ethtool -K eth0 gso off gro off tso off
ethtool -K eth0 gso on gro on tso on Actual changes: generic-segmentation-offload: on generic-receive-offload: on
ethtool -K eno1 tx on rx on Actual changes: rx-checksumming: on tx-checksumming: on tx-checksum-ip-generic: on tcp-segmentation-offload: on tx-tcp-segmentation: on
tx-tcp-mangleid-segmentation: on tx-tcp6-segmentation: on
- Disable TCP checksum offloading
ethtool -K eth0 tx off rx off
ethtool --show-offload eno0
Examples
ethtool eno1
Settings for eno1: Supported ports: [ TP ] Supported link modes: 10baseT/Half 10baseT/Full 100baseT/Half 100baseT/Full 1000baseT/Half 1000baseT/Full Supported pause frame use: No Supports auto-negotiation: Yes Supported FEC modes: Not reported Advertised link modes: 10baseT/Half 10baseT/Full 100baseT/Half 100baseT/Full 1000baseT/Half 1000baseT/Full Advertised pause frame use: Symmetric Advertised auto-negotiation: Yes Advertised FEC modes: Not reported Link partner advertised link modes: 10baseT/Half 10baseT/Full 100baseT/Half 100baseT/Full 1000baseT/Full Link partner advertised pause frame use: No Link partner advertised auto-negotiation: Yes Link partner advertised FEC modes: Not reported Speed: 1000Mb/s Duplex: Full Port: Twisted Pair PHYAD: 4 Transceiver: internal Auto-negotiation: on MDI-X: off Supports Wake-on: g Wake-on: g Current message level: 0x000000ff (255) drv probe link timer ifdown ifup rx_err tx_err Link detected: yes
ethtool eno1
Settings for eno1:
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
Supported FEC modes: Not reported
Advertised link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Full
Advertised pause frame use: No
Advertised auto-negotiation: Yes
Advertised FEC modes: Not reported
Speed: 1000Mb/s
Duplex: Full
Port: Twisted Pair
PHYAD: 1
Transceiver: internal
Auto-negotiation: on
MDI-X: off (auto)
Supports Wake-on: pumbg
Wake-on: g
Current message level: 0x00000007 (7)
drv probe link
Link detected: yes
ethtool ens3f1 Settings for ens3f1: Supported ports: [ ] Supported link modes: 1000baseT/Full 1000baseKX/Full 10000baseT/Full 1000baseX/Full 10000baseSR/Full 10000baseLR/Full Supported pause frame use: Symmetric Supports auto-negotiation: Yes Supported FEC modes: Not reported Advertised link modes: 1000baseT/Full 1000baseKX/Full 10000baseT/Full 1000baseX/Full 10000baseSR/Full 10000baseLR/Full Advertised pause frame use: No Advertised auto-negotiation: Yes Advertised FEC modes: Not reported Speed: Unknown! Duplex: Unknown! (255) Port: Other PHYAD: 0 Transceiver: internal Auto-negotiation: off Supports Wake-on: d Wake-on: d Current message level: 0x00000007 (7) drv probe link Link detected: no
ethtool -i eno1 driver: e1000e version: 3.2.6-k firmware-version: 0.5-4 expansion-rom-version: bus-info: 0000:00:1f.6 supports-statistics: yes supports-test: yes supports-eeprom-access: yes supports-register-dump: yes supports-priv-flags: no
ethtool eth2 Settings for eth2: Supported ports: [ MII ] Supported link modes: Supports auto-negotiation: No Advertised link modes: Not reported Advertised pause frame use: No Advertised auto-negotiation: No Speed: 1000Mb/s Duplex: Full Port: MII PHYAD: 0 Transceiver: external Auto-negotiation: off Current message level: 0x00000236 (566) probe link ifdown ifup intr Link detected: yes
ethtool enx0t6b8f279a99 Settings for enx0t6b8f279a99: Current message level: 0x00000007 (7) drv probe link Link detected: yes
Related terms
ip link set eth0 up
- TCP Segmentation Offload (TSO)
- Generic Segmentation Offload (GSO)
- Generic Receive Offload (GRO)
See also
ethtool
,ethtool --show-offload
,ethtool -S
- Large send offload (LSO), TCP Segmentation Offload (TSO), Generic Segmentation Offload (GSO), Generic Receive Offload (GRO)
- TCP/IP, Transport protocol, UDP, SCTP, QUIC, subnet mask, Routing protocols: BGP, routing table, Policy based routing, multicast, TCP Fast Open, RDP, TTL, RTT, MPTCP, Large send offload (LSO): (TSO, GRO, GSO, TCP checksum),
ethtool
, SCTP, 5-Tuple, Check TCP connectivity, TCP window size,/proc/sys/net/ipv4/tcp_rmem
, ack, List of TCP ports, localhost, broadcast address ifconfig
,ethtool
or obsoletemii-tool
(mii-tool -v eth0
)nmcli device show
,eth0
, Network manager- MII:
mii-tool
,ethtool
, MDI, RGMII, SGMII, GMII, SFI, XFI, XAUI, SerDes - Ethernet: MII, MDI, bonding, etherchannel, STP, ARP, MAC, STP, Jumbo frames, 802.1X, MTU, Ethernet In-Band Access (IBA), LACP, Multicast, Broadcast, SPI
Advertising: