arp(1Mtcp)


arp -- address resolution display and control

Synopsis

arp hostname

arp -a [ -n ]

arp -d [ -n ] hostname

arp -f [ -n ] filename

arp -s [ -n ] hostname ether_addr [ temp] [ pub ]

arp -S

Description

The arp program displays and modifies the IPv4-to-Ethernet address translation table, which is normally maintained by the address resolution protocol (see arp(7tcp)).

When hostname is the only argument, arp displays the current ARP entry for hostname. The host may be specified by name or by number, using Internet dot notation (see hosts(4tcp) and inet(7tcp)).

Options are interpreted as follows:

-a
Display all of the current ARP entries by reading the table from the kernel.

-d
Delete an entry for the host whose name is hostname. (This can be performed only by root.)

-f filename
Read the file filename and set multiple entries in the ARP tables. Entries in the file should be of the form

hostname ether_addr [ temp ] [ pub ]

with argument meanings as defined under the -s option.

-s hostname ether_addr [ temp ] [ pub ]
Create an ARP entry for the host whose name is hostname with the Ethernet address ether_addr. The Ethernet address is given as six colon-separated, two-digit hexadecimal numbers. The entry will be permanent unless the argument temp is specified on the command line. If pub is specified, the entry will be ``published'': that is, this system will act as an ARP server, responding to requests for hostname even though the host address is not an address of the local host.

-S
Displays the ARP statistics that the kernel maintains; these may be useful for debugging network problems.
If the -n flag is specified, arp will not display symbolic names, but instead will display numeric Internet addresses.

Diagnostics

   WARNING: arp: info overwritten for IP_address by MAC_address 

The source of this error may be:

References

arp(7tcp), ifconfig(1Mtcp), inet(3N), netstat(1Mtcp), route(1Mtcp)

RFC 826


30 January 1998
© 1998 The Santa Cruz Operation, Inc. All rights reserved.