Test for network problems and track down packet lose
Ping is a computer network administration software utility used to test the reachability of a host on an Internet Protocol network. It measures the round-trip time for messages sent from the originating host to a destination computer that are echoed back to the source.
ping [-aAbBdDfhLnOqrRUvV6] [-c count] [-F flowlabel] [-i interval] [-I interface] [-l preload] [-m mark] [-M pmtudisc_option] [-N nodeinfo_option] [-w deadline] [-W timeout] [-p pattern] [-Q tos] [-s packetsize] [-S sndbuf] [-t ttl] [-T timestamp option] [hop ...] destination