demo@demo:~$ dmesg | grep eth0
[ 2.145551] eth0: SiS 900 PCI Fast Ethernet at 0xe800, IRQ 19, 00:01:6c:d5:01:c1
[ 7.417667] ADDRCONF(NETDEV_UP): eth0: link is not ready
[ 17.876974] eth0: Media Link On 100mbps full-duplex
[ 26.144019] eth0: no IPv6 routers present
但也可能因為網路卡晶片組的關係,使用dmesg無法看見網路卡連線速度的相關訊息,這時可以使用ethtool這支程式來查看網路卡的速度。
ethtool在Ubuntu沒有內建,須先手動安裝:
demo@demo:~$ sudo apt-get update
demo@demo:~$ sudo apt-get install ethtool
ethtool必須使用管理員的權限執行,且執行時需指定要觀看的網路卡,例如:
demo@demo:~$ sudo ethtool eth0
Settings for eth0:
Supported ports: [ TP MII ]
Supported link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
Supported pause frame use: No
Supports auto-negotiation: Yes
Advertised link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
Advertised pause frame use: No
Advertised auto-negotiation: Yes
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
Speed: 100Mb/s
Duplex: Full
Port: MII
PHYAD: 1
Transceiver: internal
Auto-negotiation: on
Supports Wake-on: pg
Wake-on: d
Current message level: 0x000000c5 (197)
drv link rx_err tx_err
Link detected: yes
至於ethtool其他功能可利用man指令查看!