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28 .\" @(#)arp.8 8.1 (Berkeley) 6/6/93
36 .Nd address resolution display and control
54 .Fl s Ar hostname ether_addr
60 .Fl S Ar hostname ether_addr
70 utility displays and modifies the Internet-to-Ethernet address translation
71 tables used by the address resolution protocol
73 With no flags, the program displays the current
77 The host may be specified by name or by number,
78 using Internet dot notation.
81 .Bl -tag -width indent
83 The program displays or deletes all of the current
87 A super-user may delete an entry for the host called
94 keyword is specified, only the
98 for this host will be deleted.
102 flag may be combined with the
104 flag to delete all entries.
105 .It Fl i Ar interface
106 Limit the operation scope to the
110 Applicable only to the following operations:
111 display one, display all, delete all.
113 Show network addresses as numbers (normally
115 attempts to display addresses symbolically).
116 .It Fl s Ar hostname ether_addr
119 entry for the host called
121 with the Ethernet address
123 The Ethernet address is given as six hex bytes separated by colons.
124 The entry will be permanent unless the word
126 is given in the command.
129 is given, the entry will be
131 i.e., this system will
135 responding to requests for
137 even though the host address is not its own.
142 in which case the interfaces on this host will be examined,
143 and if one of them is found to occupy the same subnet, its
144 Ethernet address will be used.
147 keyword is also specified, this will create a
148 .Dq "published (proxy only)"
150 This type of entry is created automatically if
152 detects that a routing table entry for
158 keyword is specified the entry will be marked so that traffic to
159 the host will be discarded and the sender will be notified the
163 keyword is similar in that traffic is discarded but the sender is
165 These can be used to block external traffic to a host without
167 .It Fl S Ar hostname ether_addr
172 entry for this host will be deleted first.
176 to be read and multiple entries to be set in the
180 in the file should be of the form
182 .Bd -ragged -offset indent -compact
183 .Ar hostname ether_addr
188 with argument meanings as given above.
189 Leading whitespace and empty lines are ignored.
192 character will mark the rest of the line as a comment.