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 DMA ring sizes and interrupt moderation
• Control receive queue selection for multiqueue devices
• Upgrade firmware in flash memory

Example

To display the current parameters:

 ethtool eth0
Settings for eth0:
        Supported ports: [ TP MII ]
        Supported link modes:   10baseT/Half 10baseT/Full
                                100baseT/Half 100baseT/Full
        Supports auto-negotiation: Yes
        Advertised link modes:  10baseT/Half 10baseT/Full
                                100baseT/Half 100baseT/Full
        Advertised auto-negotiation: No
        Speed: 100Mb/s
        Duplex: Full
        Port: MII
        PHYAD: 1
        Transceiver: internal
        Auto-negotiation: off
        Supports Wake-on: g
        Wake-on: g
        Current message level: 0x00000007 (7)
        Link detected: yes

See also

• mii-tool

References

• Ethtool webpage
• Ethtool examples