arp(1M) System Administration Commands arp(1M)NAMEarp - address resolution display and control
SYNOPSISarp hostname
arp-a [-n]
arp-d hostname
arp-f filename
arp-s hostname ether_address [temp] [pub] [trail]
[permanent]
DESCRIPTION
The arp program displays and modifies the Internet-to-MAC address
translation tables used by the address resolution protocol (see
arp(7P)).
With no flags, the program displays the current ARP entry for hostname.
The host may be specified by name or by number, using Internet dot
notation.
Options that modify the ARP translation tables (-d, -f, and -s) can be
used only when the invoked command is granted the sys_net_config privi‐
lege. See privileges(5).
OPTIONS-a Display all of the current ARP entries. The definition for the
flags in the table are:
d Unverified; this is a local IP address that is currently
undergoing Duplicate Address Detection. ARP will not respond
to requests for this address until Duplicate Address Detec‐
tion completes.
o Old; this entry is aging away. If IP requests it again, a
new ARP query will be generated. This state is used for
detecting peer address changes.
y Delayed; periodic address defense and conflict detection was
unable to send a packet due to internal network use limits
for non-traffic-related messages (100 packets per hour per
interface). This occurs only on interfaces with very large
numbers of aliases.
A Authority; this machine is authoritative for this IP
address. ARP will not accept updates from other machines for
this entry.
L Local; this is a local IP address configured on one of the
machine's logical interfaces. ARP will defend this address
if another node attempts to claim it.
M Mapping; only used for the multicast entry for 224.0.0.0
P Publish; includes IP address for the machine and the
addresses that have explicitly been added by the -s option.
ARP will respond to ARP requests for this address.
S Static; entry cannot be changed by learned information. This
indicates that the permanent flag was used when creating the
entry.
U Unresolved; waiting for ARP response.
You can use the -n option with the -a option to disable the auto‐
matic numeric IP address-to-name translation. Use arp-an or arp-na to display numeric IP addresses. The arp-a option is equiva‐
lent to:
# netstat -p -f inet
...and -an and -na are equivalent to:
# netstat -pn -f inet
-d Delete an entry for the host called hostname.
Note that ARP entries for IPMP (IP Network Multipathing) data and
test addresses are managed by the kernel and thus cannot be
deleted.
-f Read the file named filename and set multiple entries in the ARP
tables. Entries in the file should be of the form:
hostname MACaddress [temp] [pub] [trail] [permanent]
See the -s option for argument definitions.
-s Create an ARP entry for the host called hostname with the MAC
address MACaddress. For example, an Ethernet address is given as
six hexadecimal bytes separated by colons. The entry will not be
subject to deletion by aging unless the word temp is specified in
the command. If the word pub is specified, the entry will be pub‐
lished, which means that this system will respond to ARP requests
for hostname even though the hostname is not its own. The word
permanent indicates that the system will not accept MAC address
changes for hostname from the network.
Solaris does not implement trailer encapsulation, and the word
trail is accepted on entries for compatibility only.
arp-s can be used for a limited form of proxy ARP when a host on
one of the directly attached networks is not physically present
on a subnet. Another machine can then be configured to respond to
ARP requests using arp-s. This is useful in certain SLIP config‐
urations.
Non-temporary proxy ARP entries for an IPMP (IP Network Multi‐
pathing) group are automatically managed by the kernel. Specifi‐
cally, if the hardware address in an entry matches the hardware
address of an IP interface in an IPMP group, and the IP address
is not local to the system, this will be regarded as an IPMP
proxy ARP entry. This entry will have its hardware address auto‐
matically adjusted in order to keep the IP address reachable so
long as the IPMP group has not entirely failed.
ARP entries must be consistent across an IPMP group. Therefore,
ARP entries cannot be associated with individual underlying IP
interfaces in an IPMP group, and must instead be associated with
the corresponding IPMP IP interface.
Note that ARP entries for IPMP data and test addresses are man‐
aged by the kernel and thus cannot be changed.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
┌─────────────────────────────┬─────────────────────────────┐
│ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
├─────────────────────────────┼─────────────────────────────┤
│Availability │SUNWcs │
└─────────────────────────────┴─────────────────────────────┘
SEE ALSOifconfig(1M), netstat(1M), attributes(5), privileges(5), arp(7P)SunOS 5.11 5 Jan 2009 arp(1M)