arping(8) - phpMan

arping(8) arping(8)

NAME
arping - sends arp and/or ip pings to a given host

SYNOPSIS
arping [-0aAbBdDeFhpqrRuUv] [-S host/ip] [-T host/ip] [-s MAC] [-t MAC] [-c count] [-i
interface] [ -w seconds ] [ -W seconds ] [ -V vlan ] [ -Q priority ] [ -g group ] <host |
-B>

arping --help

DESCRIPTION
The arping utility sends ARP and/or ICMP requests to the specified host and displays the
replies. The host may be specified by its hostname, its IP address, or its MAC address.

One request is sent each second.

When pinging an IP an ARP who-has query is sent. When pinging a MAC address a directed
broadcast ICMP Echo request is sent. For more technical explanation and an FAQ, see the
README file.

Note on timing

ARP packets are usually replied to (on a LAN) so fast that the OS task scheduler can't
keep up to get exact enough timing. On an idle system the roundtrip times will be pretty
much accurate, but with more load the timing gets less exact.

To get more exact timing on a non-idle system, re-nice arping to -15 or so.

# nice -n -15 arping foobar

This is not just an issue with arping, it is with normal ping also (at least it is on my
system). But it doesn't show up as much with ping since arping packets (when pinging IP)
doesn't traverse the IP stack when received and are therefore replied to faster.

OPTIONS
--help Show extended help. Not quite as extensive as this manpage, but more than -h.

-0 Use this option to ping with source IP address 0.0.0.0. Use this when you haven't
configured your interface yet. Note that this may get the MAC-ping unanswered.
This is an alias for -S 0.0.0.0.

-a Audible ping.

-A Only count addresses matching requested address (This *WILL* break most things you
do. Only useful if you are arpinging many hosts at once. See arping-scan-net.sh for
an example).

-b Like -0 but source broadcast source address (255.255.255.255). Note that this may
get the arping unanswered since it's not normal behavior for a host.

-B Use instead of host if you want to address 255.255.255.255.

-c count
Only send count requests.

-C count
Only wait for count replies, regardless of -c and -w.

-d Find duplicate replies. Exit with 1 if there are answers from two different MAC ad-
dresses.

-D Display answers as exclamation points and missing packets as dots. Like flood ping
on a Cisco.

-e Like -a but beep when there is no reply.

-F Don't try to be smart about the interface name. Even if this switch is not given,
-i disables this smartness.

-g group
setgid() to this group instead of the nobody group.

-h Displays a help message and exits.

-i interface
Don't guess, use the specified interface.

-m type
Type of timestamp to use for incoming packets. Use -vv when pinging to list avail-
able ones.

-p Turn on promiscious mode on interface, use this if you don't "own" the MAC address
you are using.

-P Send ARP replies instead of requests. Useful with -U.

-q Does not display messages, except error messages.

-Q priority
802.1p priority to set. Should be used with 802.1Q tag (-V). Defaults to 0.

-r Raw output: only the MAC/IP address is displayed for each reply.

-R Raw output: Like -r but shows "the other one", can be combined with -r.

-s MAC Set source MAC address. You may need to use -p with this.

-S IP Like -b and -0 but with set source address. Note that this may get the arping
unanswered if the target does not have routing to the IP. If you don't own the IP
you are using, you may need to turn on promiscious mode on the interface (with -p).
With this switch you can find out what IP-address a host has without taking an
IP-address yourself.

-t MAC Set target MAC address to use when pinging IP address.

-T IP Use -T as target address when pinging MACs that won't respond to a broadcast ping
but perhaps to a directed broadcast.

Example:

To check the address of MAC-A, use knowledge of MAC-B and IP-B.

$ arping -S <IP-B> -s <MAC-B> -p <MAC-A>

-u Show index=received/sent instead of just index=received when
pinging MACs.

-U Send unsolicited ARP. This sets the destination MAC address in
the ARP frame to the broadcast address. Unsolicited ARP is used
to update the neighbours' ARP caches.

Example:

$ arping -i <interface> -U <interface IP>

-v Verbose output. Use twice for more messages.

-V vlan
VLAN tag to set. Defaults to no VLAN tag.

-w sec Specify a timeout before ping exits regardless of how many packets have been sent or received.

-W sec Time to wait between pings.

EXAMPLES
# arping -c 3 88.1.180.225
ARPING 88.1.180.225
60 bytes from 00:11:85:4c:01:01 (88.1.180.225): index=0 time=13.910 msec
60 bytes from 00:11:85:4c:01:01 (88.1.180.225): index=1 time=13.935 msec
60 bytes from 00:11:85:4c:01:01 (88.1.180.225): index=2 time=13.944 msec

--- 88.1.180.225 statistics ---
3 packets transmitted, 3 packets received, 0% unanswered

# arping -c 3 00:11:85:4c:01:01
ARPING 00:11:85:4c:01:01
60 bytes from 88.1.180.225 (00:11:85:4c:01:01): icmp_seq=0 time=13.367 msec
60 bytes from 88.1.180.225 (00:11:85:4c:01:01): icmp_seq=1 time=13.929 msec
60 bytes from 88.1.180.225 (00:11:85:4c:01:01): icmp_seq=2 time=13.929 msec

--- 00:11:85:4c:01:01 statistics ---
3 packets transmitted, 3 packets received, 0% unanswered

# arping -C 2 -c 10 -r 88.1.180.225
00:11:85:4c:01:01
00:11:85:4c:01:01

BUGS
You have to use -B instead of arpinging 255.255.255.255, and -b instead of -S
255.255.255.255. This is libnets fault.