問題：連上網線后，有ip，但是無法訪問外網。
我的解決方案是：
1.通過命令行ifconfig命令查看以太網（即網線插口）的名稱，如下圖，'enp3s0'是網線插口（Ethernet以太網）： zhuml@zhuml-Latitude-3350:~$ ifconfig enp3s0 Link encap:Ethernet HWaddr 14:18:77:a5:24:3d inet addr:10.58.101.247 Bcast:10.58.103.255 Mask:255.255.252.0 inet6 addr: fe80::2883:9232:3f1e:fe3/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:13212 errors:0 dropped:0 overruns:0 frame:0 TX packets:1696 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:3760852 (3.7 MB) TX bytes:238743 (238.7 KB) lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:65536 Metric:1 RX packets:558 errors:0 dropped:0 overruns:0 frame:0 TX packets:558 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:72352 (72.3 KB) TX bytes:72352 (72.3 KB) wlp4s0 Link encap:Ethernet HWaddr a4:02:b9:0a:76:b1 UP BROADCAST MULTICAST MTU:1500 Metric:1 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:0 (0.0 B) TX bytes:0 (0.0 B) 2.命令行添加或修改網絡參數 zhuml@zhuml-Latitude-3350:~$ sudo gedit /etc/network/interfaces 彈出一個文本窗，如下： # interfaces(5) file used by ifup(8) and ifdown(8) auto lo iface lo inet loopback 在里面添加以太網的相關信息 # interfaces(5) file used by ifup(8) and ifdown(8) auto lo iface lo inet loopback auto esp3s0 iface esp3s0 inet dhcp 3.重啟網絡 zhuml@zhuml-Latitude-3350:~$ sudo /etc/init.d/networking restart 現在應該能夠恢復插上網線，能夠上網；