我是根。
ping 127.0.0.1 并返回错误；
root@sam-PC:~# ping 127.0.0.1
socket: Permission denied
root@sam-PC:~# ifconfig
eth0 Link encap:Ethernet HWaddr 00:00:ff:ff:00:00
inet addr:192.168.100.104 Bcast:192.168.100.255 Mask:255.255.255.0
inet6 addr: fe80::200:ffff:feff:0/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:36 errors:0 dropped:0 overruns:0 frame:0
TX packets:7 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:2220 (2.2 KB) TX bytes:524 (524.0 B)
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:16436 Metric:1
RX packets:40 errors:0 dropped:0 overruns:0 frame:0
TX packets:40 errors:0 dropped:0 overruns:0 …