
[1mNAME[0m
       fping - send ICMP ECHO_REQUEST packets to network hosts

[1mSYNOPSIS[0m
       [1mfping [22m[ [4moptions[24m ] [ [4msystems...[24m ] [1mfping6 [22m[ [4moptions[24m ] [ [4msystems...[24m ]

[1mDESCRIPTION[0m
       [1mfping [22mis a program like [1mping [22mwhich uses the Internet Control Message
       Protocol (ICMP) echo request to determine if a target host is
       responding.  [1mfping [22mdiffers from [1mping [22min 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, [1mfping [22mwill 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. [1mfping [22malso supports sending a
       specified number of pings to a target, or looping indefinitely (as in
       [1mping [22m). Unlike [1mping[22m, [1mfping [22mis meant to be used in scripts, so its
       output is designed to be easy to parse.

       The binary named [1mfping6 [22mis the same as [1mfping[22m, except that it uses IPv6
       addresses instead of IPv4.

[1mOPTIONS[0m
       [1m-a   [22mShow systems that are alive.

       [1m-A   [22mDisplay targets by address rather than DNS name.

       [1m-b [4m[22mn[24m Number of bytes of ping data to send.  The minimum size (normally
            12) allows room for the data that [1mfping [22mneeds 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 [1mping[22m. Maximum is the theoretical maximum IP datagram size
            (64K), though most systems limit this to a smaller, system-
            dependent number.

       [1m-B [4m[22mn[24m Backoff factor. In the default mode, [1mfping [22msends 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 ([1m-t[22m) is multiplied on each successive request; it must be
            entered as a floating-point number (x.y). The default is 1.5.

       [1m-c [4m[22mn[24m Number of request packets to send to each target.  In this mode, a
            line is displayed for each received response (this can suppressed
            with [1m-q [22mor [1m-Q[22m).  Also, statistics about responses for each target
            are displayed when all requests have been sent (or when
            interrupted).

       [1m-C [4m[22mn[24m Similar to [1m-c[22m, 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.

       [1m-d   [22mUse 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.

       [1m-D   [22mAdd Unix timestamps in front of output lines generated with in
            looping or counting modes ([1m-l[22m, [1m-c[22m, or [1m-C[22m).

       [1m-e   [22mShow elapsed (round-trip) time of packets.

       [1m-f   [22mRead 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

       [1m-g [4m[22maddr/mask[0m
            Generate a target list from a supplied IP netmask, or a starting
            and ending IP.  Specify the netmask or start/end in the targets
            portion of the command line. If a network with netmask is given,
            the network and broadcast addresses will be excluded. ex. To ping
            the network 192.168.1.0/24, the specified command line could look
            like either:

             fping -g 192.168.1.0/24

            or

             fping -g 192.168.1.1 192.168.1.254

       [1m-h   [22mPrint usage message.

       [1m-i [4m[22mn[24m The minimum amount of time (in milliseconds) between sending a
            ping packet to any target (default is 25).

       [1m-l   [22mLoop sending packets to each target indefinitely. Can be
            interrupted with Ctrl-C; statistics about responses for each
            target are then displayed.

       [1m-m   [22mSend pings to each of a target host's multiple interfaces.

       [1m-n   [22mSame as -d.

       [1m-p [22m<n>
            In looping or counting modes ([1m-l[22m, [1m-c[22m, or [1m-C[22m), this parameter sets
            the time in milliseconds that [1mfping [22mwaits between successive
            packets to an individual target.  Default is 1000.

       [1m-q   [22mQuiet. Don't show per-probe results, but only the final summary.
            Also don't show ICMP error messages.

       [1m-Q [4m[22mn[24m Like [1m-q[22m, but show summary results every n seconds.

       [1m-r [4m[22mn[24m Retry limit (default 3). This is the number of times an attempt at
            pinging a target will be made, not including the first try.

       [1m-s   [22mPrint cumulative statistics upon exit.

       [1m-S [4m[22maddr[0m
            Set source address.

       [1m-I [4m[22mif[0m
            Set the interface (requires SO_BINDTODEVICE support)

       [1m-t [4m[22mn[24m Initial target timeout in milliseconds (default 500). In the
            default mode, this is the amount of time that [1mfping [22mwaits for a
            response to its first request.  Successive timeouts are multiplied
            by the backoff factor specified with [1m-B[22m.  Note that this option
            has no effect looping or counting modes ([1m-l[22m, [1m-c[22m, or [1m-C[22m).

       [1m-T [4m[22mn[24m Ignored (for compatibility with fping 2.4).

       [1m-u   [22mShow targets that are unreachable.

       [1m-O [4m[22mn[24m Set the typ of service flag (TOS). [4mn[24m can be either decimal or
            hexadecimal (0xh) format.

       [1m-v   [22mPrint [1mfping [22mversion information.

       [1m-H [4m[22mn[24m Set the IP TTL field (time to live hops).

[1mAUTHORS[0m
       ·   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

       ·   David Schweikert, versions 3.0 and up

       [1mfping website: <http://www.fping.org>[0m

[1mDIAGNOSTICS[0m
       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.

[1mRESTRICTIONS[0m
       If certain options are used (i.e, a low value for [1m-i [22mand [1m-t[22m, and a high
       value for [1m-r[22m) 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,
       normal users can't specify the following:

       ·   [1m-i [4m[22mn[24m, where [4mn[24m < 10 msec

       ·   [1m-r [4m[22mn[24m, where [4mn[24m > 20

       ·   [1m-t [4m[22mn[24m, where n < 250 msec


                                  2014-05-04
