我刚买了一个 cubox-i4，但 LAN 连接出现了大问题。它建立后又崩溃了。问题是，如果我通过 LAN 将其连接到 Airport Express（通过 wifi 连接），连接是稳定的（=> 没有硬件问题）。直接连接到路由器不起作用。这是连接到路由器时的日志：
May 8 23:45:29 linaro-ubuntu-desktop kernel: PHY: 1:04 - Link is Down
May 8 23:45:30 linaro-ubuntu-desktop NetworkManager[2552]: <info> (eth0): carrier now ON (device state 100)
May 8 23:45:30 linaro-ubuntu-desktop kernel: PHY: 1:04 - Link is Up - 100/Full
May 8 23:45:36 linaro-ubuntu-desktop kernel: PHY: 1:04 - Link is Up - 1000/Half
May 8 23:45:38 linaro-ubuntu-desktop kernel: PHY: 1:04 - Link is Up - 1000/Full
May 8 23:46:00 linaro-ubuntu-desktop kernel: PHY: 1:04 - Link is Up - 1000/Half
May 8 23:46:02 linaro-ubuntu-desktop kernel: PHY: 1:04 - Link is Up - 1000/Full
May 8 23:46:24 linaro-ubuntu-desktop NetworkManager[2552]: <info> (eth0): carrier now OFF (device state 100, deferring action for 4 seconds)
May 8 23:46:24 linaro-ubuntu-desktop kernel: PHY: 1:04 - Link is Down
May 8 23:46:25 linaro-ubuntu-desktop NetworkManager[2552]: <info> (eth0): carrier now ON (device state 100)
May 8 23:46:25 linaro-ubuntu-desktop kernel: PHY: 1:04 - Link is Up - 100/Full
May 8 23:46:33 linaro-ubuntu-desktop NetworkManager[2552]: <info> (eth0): carrier now OFF (device state 100, deferring action for 4 seconds)
May 8 23:46:33 linaro-ubuntu-desktop kernel: PHY: 1:04 - Link is Down
May 8 23:46:35 linaro-ubuntu-desktop NetworkManager[2552]: <info> (eth0): carrier now ON (device state 100)
May 8 23:46:35 linaro-ubuntu-desktop kernel: PHY: 1:04 - Link is Up - 1000/Full
May 8 23:46:39 linaro-ubuntu-desktop kernel: PHY: 1:04 - Link is Up - 1000/Half
May 8 23:46:41 linaro-ubuntu-desktop kernel: PHY: 1:04 - Link is Up - 1000/Full
May 8 23:46:45 linaro-ubuntu-desktop kernel: PHY: 1:04 - Link is Up - 1000/Half
May 8 23:46:47 linaro-ubuntu-desktop kernel: PHY: 1:04 - Link is Up - 1000/Full
May 8 23:47:09 linaro-ubuntu-desktop NetworkManager[2552]: <info> (eth0): carrier now OFF (device state 100, deferring action for 4 seconds)
May 8 23:47:09 linaro-ubuntu-desktop kernel: PHY: 1:04 - Link is Down
May 8 23:47:11 linaro-ubuntu-desktop NetworkManager[2552]: <info> (eth0): carrier now ON (device state 100)
May 8 23:47:11 linaro-ubuntu-desktop kernel: PHY: 1:04 - Link is Up - 1000/Full
May 8 23:47:15 linaro-ubuntu-desktop kernel: PHY: 1:04 - Link is Up - 1000/Half
May 8 23:47:19 linaro-ubuntu-desktop kernel: PHY: 1:04 - Link is Up - 1000/Full
May 8 23:47:23 linaro-ubuntu-desktop NetworkManager[2552]: <info> (eth0): carrier now OFF (device state 100, deferring action for 4 seconds)
May 8 23:47:23 linaro-ubuntu-desktop kernel: PHY: 1:04 - Link is Down
May 8 23:47:24 linaro-ubuntu-desktop NetworkManager[2552]: <info> (eth0): carrier now ON (device state 100)
May 8 23:47:24 linaro-ubuntu-desktop kernel: PHY: 1:04 - Link is Up - 1000/Full
May 8 23:47:28 linaro-ubuntu-desktop NetworkManager[2552]: <info> (eth0): carrier now OFF (device state 100, deferring action for 4 seconds)
May 8 23:47:28 linaro-ubuntu-desktop kernel: PHY: 1:04 - Link is Down
May 8 23:47:30 linaro-ubuntu-desktop NetworkManager[2552]: <info> (eth0): carrier now ON (device state 100)
May 8 23:47:30 linaro-ubuntu-desktop kernel: PHY: 1:04 - Link is Up - 100/Full
May 8 23:47:46 linaro-ubuntu-desktop kernel: PHY: 1:04 - Link is Up - 1000/Half
May 8 23:47:48 linaro-ubuntu-desktop kernel: PHY: 1:04 - Link is Up - 1000/Full