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