DragonFly On-Line Manual Pages
FPING(8) FPING(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 < targets_file
-g addr/mask
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
-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
o Roland J. Schemers III, Stanford University, concept and versions
1.x
o RL "Bob" Morgan, Stanford University, versions 2.x
o David Papp, versions 2.3x and up
o David Schweikert, versions 3.0 and up
fping website: <http://www.fping.org>
DIAGNOSTICS
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.
RESTRICTIONS
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,
normal users can't specify the following:
o -i n, where n < 10 msec
o -r n, where n > 20
o -t n, where n < 250 msec
SEE ALSO
ping(8)
fping 2014-05-04 FPING(8)