arp(1M)                                                                arp(1M)


NAME
     arp - address resolution display and control

SYNOPSIS
     arp [ -nv ] hostname
     arp [ -nv ] -a
     arp [ -nv ] -c
     arp -d hostname
     arp -s hostname ether_addr [ temp | permanent ] [ pub ] [ proxy-only ]
     arp -f filename

DESCRIPTION
     The arp program displays and modifies the Internet-to-Ethernet address
     translation tables used by the address resolution protocol (arp(7P)).

     With no flags, the program displays the current ARP entry for hostname.
     The host can be specified by name or by number, using Internet dot
     notation.

     The arp flags are:

     -a  Display all of the current ARP entries by reading the table from the
         routing socket.  Entries that never expire are marked as permanent.
         Those that can only be changed manually are marked as static.

     -c  Clear all of the current non-permanent ARP entries from the table.

     -d hostname
         A superuser can delete an entry for the host called hostname.

     -s hostname ether_addr
         Creates an ARP entry for the host called hostname with the Ethernet
         address ether_addr.  The Ethernet address is given as six hexadecimal
         bytes separated by colons.  The entry will permanent, i.e., not time
         out, unless the word temp is given in the command.  An ARP entry can
         be overwritten by network traffic, unless the word permanent is
         given.  If this is specified, only the arp command can be used to
         change the entry.  Please note that using the permanent keyword
         causes the entry to be marked as static in arp -a output.  If the
         word pub is given, the entry is published, that is, this system will
         act as an ARP server responding to requests for hostname even though
         the host address is not its own.  If proxy-only is given, the entry
         is published, but it will not be used by this system for packets send
         to hostname, which can be useful when hostname is reached by other
         means such as a PPP link.

     -f filename
         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 | permanent ] [ pub ] [ proxy-only ]

         with argument meanings as given above.

     -n  Causes mapping of IP addresses to hostnames to be suppressed.

     -v  Causes additional information to be displayed, such as the interface
         associated with entries and the age of the arp entries. Only a
         superuser may use this flag.

EXAMPLES
     Command lines are followed by the output.

     A completed successful entry:

          # arp moose
          moose (192.26.72.5) at 8:0:69:2:24:3e

     A completed successful entry that is marked permanent and published:

          # arp rainbow
          rainbow (192.26.72.3) at 8:0:69:2:4:94 permanent published

     An incomplete entry:

          # arp ender
          ender (192.26.72.246) at (incomplete)

     A nonexistent entry:

          # arp foobar
          foobar (192.26.72.1) -- no entry


SEE ALSO
     ifconfig(1M), arp(7P), inet(7F).


                                                                        Page 2