ethtool
ethtool
Query or control network driver and hardware settings
ethtool eth0
Settings for eth0:
Supported ports: [ TP ]
Supported link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Full
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: 0
Transceiver: internal
Auto-negotiation: on
MDI-X: Unknown
Supports Wake-on: d
Wake-on: d
Current message level: 0x00000007 (7)
Link detected: yes
To query interface statistics
ethtool -S eth0
Blink ethernet device 0 for 15 seconds
where [N] is Number of seconds to blink
ethtool -p eth0 15
Check Network Hardware
lshw -C Network
mii-tool
mii-tool eth0
eth0: no autonegotiation, 1000baseT-FD flow-control, link ok
Change Auto-negotiation
ifdown eth0
ethtool -s eth0 autoneg off
ifup eth0
Change the Speed
ethtool -s eth0 speed 100 autoneg off
Display Ethernet Driver Settings
ethtool -i eth0
Display Auto-negotiation, RX and TX
ethtool -a eth0
Display Network Statistics
ethtool -S eth0