PING(1M)                                                 PING(1M)



     NAME
          ping - send ICMP ECHO_REQUEST packets to network hosts

     SYNOPSIS
          /etc/ping [ -r ] [ -v ] host [ packetsize ] [ count ]

     DESCRIPTION
          The DARPA Internet is a large and complex aggregation of
          network hardware, connected together by gateways.  Tracking
          a single-point hardware or software failure can often be
          difficult.  Ping utilizes the ICMP protocol's mandatory
          ECHO_REQUEST datagram to elicit an ICMP ECHO_RESPONSE from a
          host or gateway.  ECHO_REQUEST datagrams (``pings'') have an
          IP and ICMP header, followed by a struct timeval, and then
          an arbitrary number of ``pad'' bytes used to fill out the
          packet.  Default datagram length is 64 bytes, but this may
          be changed using the command-line option.  Other options
          are:

          -r   Bypass the normal routing tables and send directly to a
               host on an attached network.  If the host is not on a
               directly-attached network, an error is returned.  This
               option can be used to ping a local host through an
               interface that has no route through it (e.g., after the
               interface was dropped by routed(1M)).

          -v   Verbose output.  ICMP packets other than ECHO RESPONSE
               that are received are listed.

          When using ping for fault isolation, it should first be run
          on the local host, to verify that the local network
          interface is up and running.  Then, hosts and gateways
          further and further away should be ``pinged''.  Ping sends
          one datagram per second, and prints one line of output for
          every ECHO_RESPONSE returned.  No output is produced if
          there is no response.  If an optional count is given, only
          that number of requests is sent.  Round-trip times and
          packet loss statistics are computed.  When all responses
          have been received or the program times out (with a count
          specified), or if the program is terminated with a SIGINT, a
          brief summary is displayed.

          This program is intended for use in network testing,
          measurement and management.  It should be used primarily for
          manual fault isolation.  Because of the load it could impose
          on the network, it is unwise to use ping during normal
          operations or from automated scripts.

     AUTHOR
          Mike Muuss

     SEE ALSO



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     PING(1M)                                                 PING(1M)



          netstat(1), ifconfig(1M)

     ORIGIN
          4.2 BSD



















































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