PING forum.ubuntu.org.cn (104.21.59.99) 56(84) bytes of data.
64 bytes from 104.21.59.99 (104.21.59.99): icmp_seq=1 ttl=59 time=5.57 ms
64 bytes from 104.21.59.99 (104.21.59.99): icmp_seq=2 ttl=59 time=5.47 ms
64 bytes from 104.21.59.99 (104.21.59.99): icmp_seq=3 ttl=59 time=5.62 ms

--- forum.ubuntu.org.cn ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2002ms
rtt min/avg/max/mdev = 5.473/5.557/5.627/0.063 ms