Provided by: fping_2.4b2-to-ipv6-16.1_amd64 bug


       fping - send ICMP ECHO_REQUEST packets to network hosts


       fping [ options ] [ systems... ]


       fping  is  a  program like ping(8) which uses the Internet Control Message Protocol (ICMP)

       a target, or looping indefinitely (as in ping ).



       -a   Show systems that are alive.

       -A   Display targets by address rather than DNS name.

            a smaller, system-dependent number.

       -Bn  In  the  default  mode,  fping  sends  several requests to a target before giving up,
            as a floating-point number (x.y).  The default is 1.5.

            when interrupted).

            automated response-time statistics gathering.  For example:

            % fping -C 5 -q somehost

            somehost : 91.7 37.0 29.2 - 36.8

            indicating that no response was received to the fourth request.

            of IP addresses as input and print hostnames in the output.


       -f   Read list of targets from a file.  This option can only be used  by  the  root  user.
            Regular users should pipe in the file via stdin:

            % fping < targets_file



            fping -g


            fping -g

       -h   Print usage message.

            target (default is 25).

            statistics about responses for each target are then displayed.


       -n   Same as -d.

            milliseconds that fping waits between successive packets  to  an  individual  target.
            Default is 1000.


       -Qn  Like -q, but show summary results every n seconds.

            will be made, not including the first try.

       -s   Print cumulative statistics upon exit.

            Set source address.

            timeouts are multiplied by the backoff factor.

       -Tn  Select timeout in seconds (default 10).

       -u   Show targets that are unreachable.

       -v   Print fping version information.


       The following perl script will check a list of hosts and send mail if any are unreachable.
       It  uses  the  open2 function which allows a program to be opened for reading and writing.
       fping does not start pinging the list of systems until it reads EOF, which it  gets  after
       INPUT  is  closed.   Sure  the  open2 usage is not needed in this example, but it's a good
       open2 example none the less.

       require '';

       $MAILTO = "root";




       if ($#output != -1) {
        print MAIL @output;
        close MAIL;

       that are currently reachable.



         # do it


       David Papp, versions 2.3x and up,
       fping website:


       Exit status is 0 if all the hosts are reachable, 1 if some hosts were  unreachable,  2  if
       any  IP addresses were not found, 3 for invalid command line arguments, and 4 for a system
       call failure.


       Ha! If we knew of any we would have fixed them!


       If certain options are used (i.e, a low value for -i and -t, and a high value for  -r)  it
       is  possible  to flood the network. This program must be installed as setuid root in order
       to open up a raw socket, or must be run by root. In order to stop mere mortals from hosing
       the  network  (when  fping  is  installed  setuid  root)  , normal users can't specify the

        -i n   where n < 10  msec
        -r n   where n > 20
        -t n   where n < 250 msec

