ARPD(8) System Manager's Manual ARPD(8)
arpd - userspace arp daemon.
Usage: arpd [ -lkh? ] [ -a N ] [ -b dbase ] [ -B number ] [ -f file ] [-p interval ] [ -n
time ] [ -R rate ] [ ]
The arpd daemon collects gratuitous ARP information, saving it on local disk and feeding
it to the kernel on demand to avoid redundant broadcasting due to limited size of the ker‐
nel ARP cache.
-h -? Print help
-l Dump the arpd database to stdout and exit. The output consists of three columns:
the interface index, the IP address of the interface, and the MAC address of the
interface. Negative entries for dead hosts are also shown, in this case the MAC
address is replaced by the word FAILED followed by a colon and the most recent time
when the fact that the host is dead was proven.
Read and load an arpd database from FILE in a text format similar to that dumped by
option -l. Exit after load, possibly listing resulting database, if option -l is
also given. If FILE is -, stdin is read to get the ARP table.
the location of the database file. The default location is /var/lib/arpd/arpd.db
With this option, arpd not only passively listens for ARP packets on the interface,
but also sends broadcast queries itself. NUMBER is the number of such queries to
make before a destination is considered dead. When arpd is started as kernel helper
(i.e. with app_solicit enabled in sysctl or even with option -k) without this
option and still did not learn enough information, you can observe 1 second gaps in
service. Not fatal, but not good.
-k Suppress sending broadcast queries by the kernel. This option only makes sense
together with option -a.