replies to any ARP request for an IP address
matching the specified destination net
the hardware MAC address of the specified
, but only after determining if
another host already claims it.
Any IP address claimed by farpd
forgotten after a period of inactivity or after a hard timeout, and is
relinquished if the real owner shows up.
This enables a single host to claim all unassigned addresses on a LAN for
network monitoring or simulation.
exits on an interrupt or termination signal.
Note: The program name farpd
has been changed in
Debian GNU/Linux from the original name ( arpd
) to avoid name clash
with other ARP daemons.
The options are as follows:
- Do not daemonize, and enable verbose debugging
- Listen on interface. If
unspecified, farpd searches the system
interface list for the lowest numbered, configured ``up'' interface
- The IP address or network (specified in CIDR notation) or
IP address ranges to claim (e.g. ``10.0.0.3'', ``10.0.0.0/16'' or
``10.0.0.5-10.0.0.15''). If unspecified,
farpd will attempt to claim any IP address it
sees an ARP request for. Mutiple addresses may be specified.
will respond too slowly to ARP requests for
some applications. In order to ensure that it does not claim existing IP
addresses it will send two ARP request and wait for a reply. This slowness
affects the nmap
network scanning tool, and possibly others, which uses
by default ARP when scanning local networks. The answers from
will come after the tool has timeout
waiting for the ARP replies and, consequently, IP addresses claimed by
will not be discovered.
sends the ARP replies to the
broadcast address of the network and not to the host that send the ARP
request. Some systems and applications (notably nmap
) will not handled
these requests and expect directed ARP replies (i.e. targeted specifically to
the host that sent the request and not to the network)
Dug Song ⟨email@example.com⟩, Niels Provos