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.\" $FreeBSD: src/usr.sbin/arp/arp.8,v 1.8.2.11 2003/03/11 21:13:48 trhodes Exp $ 34.\" $DragonFly: src/usr.sbin/arp/arp.8,v 1.2 2003/06/17 04:29:52 dillon Exp $ 35.\" 36.Dd June 6, 1993 37.Dt ARP 8 38.Os 39.Sh NAME 40.Nm arp 41.Nd address resolution display and control 42.Sh SYNOPSIS 43.Nm 44.Op Fl n 45.Ar hostname 46.Nm 47.Op Fl n 48.Fl a 49.Nm 50.Fl d Ar hostname 51.Op Cm pub 52.Nm 53.Fl d 54.Fl a 55.Nm 56.Fl s Ar hostname ether_addr 57.Op Cm temp 58.Op Cm pub Op Cm only 59.Nm 60.Fl S Ar hostname ether_addr 61.Op Cm temp 62.Op Cm pub Op Cm only 63.Nm 64.Fl f Ar filename 65.Sh DESCRIPTION 66The 67.Nm 68utility displays and modifies the Internet-to-Ethernet address translation 69tables used by the address resolution protocol 70.Pq Xr arp 4 . 71With no flags, the program displays the current 72.Tn ARP 73entry for 74.Ar hostname . 75The host may be specified by name or by number, 76using Internet dot notation. 77.Pp 78Available options: 79.Bl -tag -width indent 80.It Fl a 81The program displays or deletes all of the current 82.Tn ARP 83entries. 84.It Fl d 85A super-user may delete an entry for the host called 86.Ar hostname 87with the 88.Fl d 89flag. 90If the 91.Cm pub 92keyword is specified, only the 93.Dq published 94.Tn ARP 95entry 96for this host will be deleted. 97.Pp 98Alternatively, the 99.Fl d 100flag may be combined with the 101.Fl a 102flag to delete all entries. 103.It Fl n 104Show network addresses as numbers (normally 105.Nm 106attempts to display addresses symbolically). 107.It Fl s Ar hostname ether_addr 108Create an 109.Tn ARP 110entry for the host called 111.Ar hostname 112with the Ethernet address 113.Ar ether_addr . 114The Ethernet address is given as six hex bytes separated by colons. 115The entry will be permanent unless the word 116.Cm temp 117is given in the command. 118If the word 119.Cm pub 120is given, the entry will be 121.Dq published ; 122i.e., this system will 123act as an 124.Tn ARP 125server, 126responding to requests for 127.Ar hostname 128even though the host address is not its own. 129In this case the 130.Ar ether_addr 131can be given as 132.Cm auto 133in which case the interfaces on this host will be examined, 134and if one of them is found to occupy the same subnet, its 135Ethernet address will be used. 136If the 137.Cm only 138keyword is also specified, this will create a 139.Dq "published (proxy only)" 140entry. 141This type of entry is created automatically if 142.Nm 143detects that a routing table entry for 144.Ar hostname 145already exists. 146.It Fl S Ar hostname ether_addr 147Is just like 148.Fl s 149except any existing 150.Tn ARP 151entry for this host will be deleted first. 152.It Fl f Ar filename 153Cause the file 154.Ar filename 155to be read and multiple entries to be set in the 156.Tn ARP 157tables. Entries 158in the file should be of the form 159.Pp 160.Bd -ragged -offset indent -compact 161.Ar hostname ether_addr 162.Op Cm temp 163.Op Cm pub 164.Ed 165.Pp 166with argument meanings as given above. 167Leading whitespace and empty lines are ignored. 168A 169.Ql # 170character will mark the rest of the line as a comment. 171.El 172.Sh SEE ALSO 173.Xr inet 3 , 174.Xr arp 4 , 175.Xr ifconfig 8 176.Sh HISTORY 177The 178.Nm 179utility appeared in 180.Bx 4.3 . 181