1.\" Copyright (c) 1985, 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 3. All advertising materials mentioning features or use of this software 13.\" must display the following acknowledgement: 14.\" This product includes software developed by the University of 15.\" California, Berkeley and its contributors. 16.\" 4. Neither the name of the University nor the names of its contributors 17.\" may be used to endorse or promote products derived from this software 18.\" without specific prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" @(#)arp.8 8.1 (Berkeley) 6/6/93 33.\" 34.Dd June 6, 1993 35.Dt ARP 8 36.Os BSD 4.3 37.Sh NAME 38.Nm arp 39.Nd address resolution display and control 40.Sh SYNOPSIS 41.Nm arp 42.Op Fl n 43.Ar hostname 44.Nm arp 45.Op Fl n 46.Fl a 47.Nm arp 48.Fl d Ar hostname 49.Op Ar proxy 50.Nm arp 51.Fl d 52.Fl a 53.Nm arp 54.Fl s Ar hostname ether_addr 55.Op Ar temp 56.Op Ar pub 57.Nm arp 58.Fl S Ar hostname ether_addr 59.Op Ar temp 60.Op Ar pub 61.Nm arp 62.Fl f Ar filename 63.Sh DESCRIPTION 64The 65.Nm 66program displays and modifies the Internet-to-Ethernet address translation 67tables used by the address resolution protocol 68.Pq Xr arp 4 . 69With no flags, the program displays the current 70.Tn ARP 71entry for 72.Ar hostname . 73The host may be specified by name or by number, 74using Internet dot notation. 75.Pp 76Available options: 77.Bl -tag -width Ds 78.It Fl a 79The program displays or deletes all of the current 80.Tn ARP 81entries. 82.It Fl d 83A super-user may delete an entry for the host called 84.Ar hostname 85with the 86.Fl d 87flag. May be combined with the 88.Fl a 89flag to delete all entries. 90.It Fl n 91Show network addresses as numbers (normally 92.Nm 93attempts to display addresses symbolically). 94.It Fl s Ar hostname ether_addr 95Create an 96.Tn ARP 97entry for the host called 98.Ar hostname 99with the Ethernet address 100.Ar ether_addr . 101The Ethernet address is given as six hex bytes separated by colons. 102The entry will be permanent unless the word 103.Ar temp 104is given in the command. 105If the word 106.Ar pub 107is given, the entry will be "published"; i.e., this system will 108act as an 109.Tn ARP 110server, 111responding to requests for 112.Ar hostname 113even though the host address is not its own. 114In this case the ether_addr can be given as ``auto'' 115in which case the interfaces on this host will be examined, 116and if one of them is found to occupy the same subnet, its 117ether_addr will be used. 118.It Fl S Ar hostname ether_addr 119Is just like 120.Fl s 121except any existing arp entry for this host will be deleted first. 122.It Fl f 123Causes the file 124.Ar filename 125to be read and multiple entries to be set in the 126.Tn ARP 127tables. Entries 128in the file should be of the form 129.Pp 130.Bd -filled -offset indent -compact 131.Ar hostname ether_addr 132.Op Ar temp 133.Op Ar pub 134.Ed 135.Pp 136with argument meanings as given above. 137.El 138.Sh SEE ALSO 139.Xr inet 3 , 140.Xr arp 4 , 141.Xr ifconfig 8 142.Sh HISTORY 143The 144.Nm 145command appeared in 146.Bx 4.3 . 147