Ping command (a TCP/IP tool to check connectivity on a network)

The ping command is not really a tool used to troubleshoot DNS issues. Instead the ping command is used to determine whether a host is connected to the network. It uses the Internet Control Message Protocol (ICMP). Invoking the ping command sends an echo request message to the remote host then waits for a reply. If a reply is returned before the timeout period ( this can be set by the user) the round trip for the message and reply are command resultsThere exist a group of command-line options for use with ping the general syntax is;

 ping [ -taf] [-n count] [-l length] [-i ttl] [-v tos] [-r count] [-s count] [[-j host-list] | [-k host-list]] 
[-w timeout] destination address

The following options are available;

-t ping runs continuously until stopped
-a used to resolve addresses to host names
-f do not fragment
-n specifies a count for the number of ping requests to send
-l specifies a length for the echo request
-i specifies a time-to-live (TTL)(form 1 – 225)
-v user can change the Type of Service (TOS)
-r records route for the requests and replys (max of nine hosts)
-s produces time stamps for the number of hops specified