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fping6(8)                                                                                                   fping6(8)



NAME
       fping - send ICMP ECHO_REQUEST packets to network hosts

SYNOPSIS
       fping [ options ] [ systems... ] fping6 [ options ] [ systems... ]

DESCRIPTION
       fping is a program like ping which uses the Internet Control Message Protocol (ICMP) echo request to determine
       if a target host is responding.  fping differs from ping in that you can specify any number of targets on the
       command line, or specify a file containing the lists of targets to ping.  Instead of sending to one target
       until it times out or replies, fping will send out a ping packet and move on to the next target in a round-
       robin fashion.  In the default mode, if a target replies, it is noted and removed from the list of targets to
       check; if a target does not respond within a certain time limit and/or retry limit it is designated as
       unreachable. fping also supports sending a specified number of pings to a target, or looping indefinitely (as
       in ping ). Unlike ping, fping is meant to be used in scripts, so its output is designed to be easy to parse.

       The binary named fping6 is the same as fping, except that it uses IPv6 addresses instead of IPv4.

OPTIONS
       -a   Show systems that are alive.

       -A   Display targets by address rather than DNS name.

       -b n Number of bytes of ping data to send.  The minimum size (normally 12) allows room for the data that fping
            needs to do its work (sequence number, timestamp).  The reported received data size includes the IP
            header (normally 20 bytes) and ICMP header (8 bytes), so the minimum total size is 40 bytes.  Default is
            56, as in ping. Maximum is the theoretical maximum IP datagram size (64K), though most systems limit this
            to a smaller, system-dependent number.

       -B n Backoff factor. In the default mode, fping sends several requests to a target before giving up, waiting
            longer for a reply on each successive request.  This parameter is the value by which the wait time (-t)
            is multiplied on each successive request; it must be entered as a floating-point number (x.y). The
            default is 1.5.

       -c n Number of request packets to send to each target.  In this mode, a line is displayed for each received
            response (this can suppressed with -q or -Q).  Also, statistics about responses for each target are
            displayed when all requests have been sent (or when interrupted).

       -C n Similar to -c, but the per-target statistics are displayed in a format designed for automated response-
            time statistics gathering. For example:

             % fping -C 5 -q somehost
             somehost : 91.7 37.0 29.2 - 36.8

            shows the response time in milliseconds for each of the five requests, with the "-" indicating that no
            response was received to the fourth request.

       -d   Use DNS to lookup address of return ping packet. This allows you to give fping a list of IP addresses as
            input and print hostnames in the output.

       -D   Add Unix timestamps in front of output lines generated with in looping or counting modes (-l, -c, or -C).

       -e   Show elapsed (round-trip) time of packets.

       -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 -g 192.168.1.1 192.168.1.254

       -h   Print usage message.

       -i n The minimum amount of time (in milliseconds) between sending a ping packet to any target (default is 25).

       -l   Loop sending packets to each target indefinitely. Can be interrupted with Ctrl-C; statistics about
            responses for each target are then displayed.

       -m   Send pings to each of a target host's multiple interfaces.

       -n   Same as -d.

       -p <n>
            In looping or counting modes (-l, -c, or -C), this parameter sets the time in milliseconds that fping
            waits between successive packets to an individual target.  Default is 1000.

       -q   Quiet. Don't show per-probe results, but only the final summary. Also don't show ICMP error messages.

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

       -r n Retry limit (default 3). This is the number of times an attempt at pinging a target will be made, not
            including the first try.

       -s   Print cumulative statistics upon exit.

       -S addr
            Set source address.

       -I if
            Set the interface (requires SO_BINDTODEVICE support)

       -t n Initial target timeout in milliseconds (default 500). In the default mode, this is the amount of time
            that fping waits for a response to its first request.  Successive timeouts are multiplied by the backoff
            factor specified with -B.  Note that this option has no effect looping or counting modes (-l, -c, or -C).

       -T n Ignored (for compatibility with fping 2.4).

       -u   Show targets that are unreachable.

       -O n Set the typ of service flag (TOS). n can be either decimal or hexadecimal (0xh) format.

       -v   Print fping version information.

       -H n Set the IP TTL field (time to live hops).

AUTHORS
       ·   Roland J. Schemers III, Stanford University, concept and versions 1.x

       ·   RL "Bob" Morgan, Stanford University, versions 2.x

       ·   David Papp, versions 2.3x and up


       ·   -i n, where n < 10 msec

       ·   -r n, where n > 20

       ·   -t n, where n < 250 msec

SEE ALSO
       ping(8)



fping                                                 2014-05-04                                            fping6(8)