Notes to Self

Alex Sokolsky's Notes on Computers and Programming


Here are few examples of ethtool use. More examples, man page.

ethtool is being supplanted by nmcli, cli to NetworkManager.

Display NIC settings

root@pmox3:~# ethtool enp1s0
Settings for enp1s0:
        Supported ports: [ TP ]
        Supported link modes:   10baseT/Half 10baseT/Full
                                100baseT/Half 100baseT/Full
        Supported pause frame use: Symmetric Receive-only
        Supports auto-negotiation: Yes
        Supported FEC modes: Not reported
        Advertised link modes:  10baseT/Half 10baseT/Full
                                100baseT/Half 100baseT/Full
        Advertised pause frame use: Symmetric Receive-only
        Advertised auto-negotiation: Yes
        Advertised FEC modes: Not reported
        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
        Link partner advertised FEC modes: Not reported
        Speed: 1000Mb/s
        Duplex: Full
        Auto-negotiation: on
        Port: Twisted Pair
        PHYAD: 0
        Transceiver: internal
        MDI-X: Unknown
        Supports Wake-on: pumbg
        Wake-on: g
        Current message level: 0x00000033 (51)
                               drv probe ifdown ifup
        Link detected: yes

Get MAC address

root@pmox2:~# ethtool -P eno1
Permanent address: 6c:2b:59:f8:0d:f6
root@pmox2:~# ethtool -P vmbr0
Permanent address: not set

Display the driver used

root@pmox2:~# ethtool -i eno1
driver: e1000e
version: 5.15.39-1-pve
firmware-version: 0.5-4
bus-info: 0000:00:1f.6
supports-statistics: yes
supports-test: yes
supports-eeprom-access: yes
supports-register-dump: yes
supports-priv-flags: yes
root@pmox2:~# ethtool -i vmbr0
driver: bridge
version: 2.3
firmware-version: N/A
bus-info: N/A
supports-statistics: no
supports-test: no
supports-eeprom-access: no
supports-register-dump: no
supports-priv-flags: no

Display NIC statistics

Use ethtool -S enp1s0 or, better yet, watch -d "ethtool -S eno1".

root@pmox3:~# ethtool -S enp1s0
NIC statistics:
     tx_packets: 12
     rx_packets: 5625
     tx_errors: 0
     rx_errors: 0
     rx_missed: 0
     align_errors: 0
     tx_single_collisions: 0
     tx_multi_collisions: 0
     unicast: 0
     broadcast: 2206
     multicast: 3419
     tx_aborted: 0
     tx_underrun: 0
     tx_octets: 1694
     rx_octets: 1310239
     rx_multicast64: 0
     tx_unicast64: 1
     tx_broadcast64: 0
     tx_multicast64: 11
     tx_pause_on: 0
     tx_pause_off: 0
     tx_pause_all: 0
     tx_deferred: 0
     tx_late_collision: 0
     tx_all_collision: 0
     tx_aborted32: 0
     align_errors32: 0
     rx_frame_too_long: 0
     rx_runt: 0
     rx_pause_on: 0
     rx_pause_off: 0
     rx_pause_all: 0
     rx_unknown_opcode: 0
     rx_mac_error: 0
     tx_underrun32: 0
     rx_mac_missed: 0
     rx_tcam_dropped: 0
     tdu: 0
     rdu: 0

NIC test

root@pmox3:~# ethtool -t eno1
The test result is PASS
The test extra info:
Register test  (offline)         0
Eeprom test    (offline)         0
Interrupt test (offline)         0
Loopback test  (offline)         0
Link test   (on/offline)         0
root@pmox3:~# ethtool -t enp1s0
Cannot test: Operation not supported