1 .TH IP\-NEIGHBOUR 8 "20 Dec 2011" "iproute2" "Linux"
3 ip-neighbour \- neighbour/arp tables management.
12 .RI " { " COMMAND " | "
17 .BR "ip neigh" " { " add " | " del " | " change " | " replace " } { "
21 .BR nud " { " permanent " | " noarp " | " stale " | " reachable " } ] | " proxy
27 .BR "ip neigh" " { " show " | " flush " } [ " proxy " ] [ " to
40 objects that establish bindings between protocol addresses and
41 link layer addresses for hosts sharing the same link.
42 Neighbour entries are organized into tables. The IPv4 neighbour table
43 is known by another name - the ARP table.
46 The corresponding commands display neighbour bindings
47 and their properties, add new neighbour entries and delete old ones.
49 .SS ip neighbour add - add a new neighbour entry
50 .SS ip neighbour change - change an existing entry
51 .SS ip neighbour replace - add a new entry or change an existing one
53 These commands create new neighbour records or update existing ones.
56 .BI to " ADDRESS " (default)
57 the protocol address of the neighbour. It is either an IPv4 or IPv6 address.
61 the interface to which this neighbour is attached.
64 .BI lladdr " LLADDRESS"
65 the link layer address of the neighbour.
72 the state of the neighbour entry.
74 is an abbreviation for 'Neighbour Unreachability Detection'.
75 The state can take one of the following values:
79 - the neighbour entry is valid forever and can be only
80 be removed administratively.
84 - the neighbour entry is valid. No attempts to validate
85 this entry will be made but it can be removed when its lifetime expires.
89 - the neighbour entry is valid until the reachability
94 - the neighbour entry is valid but suspicious.
97 does not change the neighbour state if it was valid and the address
98 is not changed by this command.
101 .SS ip neighbour delete - delete a neighbour entry
102 This command invalidates a neighbour entry.
105 The arguments are the same as with
115 Attempts to delete or manually change a
117 entry created by the kernel may result in unpredictable behaviour.
118 Particularly, the kernel may try to resolve this address even
121 interface or if the address is multicast or broadcast.
123 .SS ip neighbour show - list neighbour entries
125 This commands displays neighbour tables.
128 .BI to " ADDRESS " (default)
129 the prefix selecting the neighbours to list.
133 only list the neighbours attached to this device.
137 list neighbour proxies.
141 only list neighbours which are not currently in use.
145 only list neighbour entries in this state.
147 takes values listed below or the special value
149 which means all states. This option may occur more than once.
150 If this option is absent,
152 lists all entries except for
157 .SS ip neighbour flush - flush neighbour entries
158 This command flushes neighbour tables, selecting
159 entries to flush by some criteria.
162 This command has the same arguments as
164 The differences are that it does not run when no arguments are given,
165 and that the default neighbour states to be flushed do not include
173 option, the command becomes verbose. It prints out the number of
174 deleted neighbours and the number of rounds made to flush the
175 neighbour table. If the option is given
178 also dumps all the deleted neighbours.
184 Shows the current neighbour table in kernel.
187 ip neigh flush dev eth0
189 Removes entries in the neighbour table on device eth0.
197 Original Manpage by Michail Litvak <mci@owl.openwall.com>