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ARP(8)                      System Manager's Manual                     ARP(8)

NAME
     arp - address resolution display and control

SYNOPSIS
     arp [-n] hostname
     arp [-nv] -a
     arp [-v] -d -a
     arp [-v] -d hostname [proxy]
     arp -s hostname ether_addr [temp] [pub [proxy]]
     arp -f filename

DESCRIPTION
     The arp program displays and modifies the Internet-to-Ethernet address
     translation tables used by the address resolution protocol (arp(4)).
     With no flags, the program displays the current ARP entry for hostname.
     The host may be specified by name or by number, using Internet dot
     notation.

     The state of the arp entry is shown as a single letter preceded by the
     time the state is applicable for:
     D       Delay
     I       Incomplete
     N       Nostate
     P       Probe
     R       Reachable
     S       Stale
     U       Unreachable
     W       Waitdelete
     ?       Unknown state (should never happen).

     Available options:

     -a      The program displays all of the current ARP entries.

     -d      A super-user may delete an entry for the host called hostname
             with the -d flag.  If the proxy keyword is specified, only the
             published "proxy only" ARP entry for this host will be deleted.
             If used with -a instead of a hostname, it will delete all arp
             entries.

     -f      Causes the file filename to be read and multiple entries to be
             set in the ARP tables.  Entries in the file should be of the form

                   hostname ether_addr [temp] [pub]

             with argument meanings as described below.

     -n      Show network addresses as numbers (normally arp attempts to
             display addresses symbolically).

     -s hostname ether_addr
             Create an ARP entry for the host called hostname with the
             Ethernet address ether_addr.  The Ethernet address is given as
             six hex bytes separated by colons.  The entry will be permanent
             unless the word temp is given in the command.  If the word pub is
             given, the entry will be "published"; i.e., this system will act
             as an ARP server, responding to requests for hostname even though
             the host address is not its own.

             If the word proxy is also given, the published entry will be a
             "proxy only" entry.  In this case the ether_addr can be given as
             auto in which case the interfaces on this host will be examined,
             and if one of them is found to occupy the same subnet, its
             Ethernet address will be used.

     -v      Display verbose information when adding or deleting ARP entries.

SEE ALSO
     inet(3), arp(4), ifconfig(8)

HISTORY
     The arp command appeared in 4.3BSD.

NetBSD 10.99                   December 5, 2021                   NetBSD 10.99