我使用的是 Ubuntu 12.04，最近我買了 USB 轉乙太網路轉接器。
dmesg 指令顯示型號為「Davicom DM9601 USB 乙太網路」。我無法使用 ethtool 修改其任何設定。
jesin@localhost:~$ sudo ethtool eth1
Settings for eth1:
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: Symmetric Receive-only
Advertised auto-negotiation: Yes
Link partner advertised link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
Link partner advertised pause frame use: Symmetric Receive-only
Link partner advertised auto-negotiation: Yes
Speed: 100Mb/s
Duplex: Full
Port: MII
PHYAD: 0
Transceiver: internal
Auto-negotiation: on
Current message level: 0x00000007 (7)
drv probe link
Link detected: yes
當我嘗試將適配器的速度更改為 10Mbps 時，我得到
jesin@localhost:~$ sudo ethtool -s eth1 speed 10
Cannot advertise speed 10
我什至無法更改連接埠類型
jesin@localhost:~$ sudo ethtool -s eth1 port tp
Cannot set new settings: Invalid argument
not setting port
是什麼導致了這個問題？
附加資訊：
jesin@localhost:~$ sudo ethtool --version
ethtool version 3.1
jesin@localhost:~$ uname -r
3.2.0-39-generic