OSF

NAME

arp − Displays and controls Address Resolution Protocol (ARP) tables

SYNOPSIS

arp hostname

arp -a [system] [core]

arp -d hostname

arp -f filename

arp -s hostname hardware_addr [temp] [pub] [trail]

The arp command displays and modifies the ARP tables that map Internet addresses to network hardware addresses. 

FLAGS

-a [system] [core]
Displays all of the current ARP entries by reading the table from the file core (default /dev/kmem) based on the kernel file system (default /vmunix). 

-d hostnameDeletes the entry for hostname if the user issuing the command has superuser authority. 

-f filenameReads entries from filename and adds those entries to the ARP tables.  Entries in the file are in the following form:

hostname hardware_addr [temp] [pub] [trail]

where:

hostnameSpecifies the remote host identified by the entry. 

hardware_addr
Specifies the hardware address of the remote host. The address is given as 6 hexadecimal bytes separated by colons.

tempSpecifies that this ARP table entry is temporary.  When this argument is not used, the table entry is permanent. 

pubIndicates that the table entry will be published and that the current system will act as an ARP server, responding to requests for hostname even though the host address is not its own. 

trailIndicates that the trailer encapsulation may be sent to this host. 

-shostname hardware_addr [temp] [pub] [trail]
Creates a single ARP entry for hostname.  The arguments are explained in the discussion of the -f flag. 

DESCRIPTION

The arp command displays or modifies the current ARP entry for the host specified by hostname.  The host may be specified by name or number, using Internet dot notation. 

With no flags, the program displays the current ARP entry for hostname. 

The ARP tables can be displayed by any user, but only the superuser can modify them. 

EXAMPLES

     1.To display the ARP address mapping tables for the local host that has one interface defined, enter:

arp -a
 milan.ber.org (555.555.5.555) at 0:dd:0:39:af:0
shaw.cjr.org (555.555.5.555) at 8:0:2b:15:42:83 trailers

     2.To add a single entry for the remote host laszlo to the ARP mapping tables temporarily, enter:

arp -s laszlo 0:dd:0:a:85:0 temp

Note that you must have superuser authority to execute this command. 

     3.To add multiple entries to the ARP mapping tables from the file newentries, enter:

arp -f newentries

Note that you must have superuser authority to execute this command. 

FILES

/usr/sbin/arp
Specifies the command path

RELATED INFORMATION

Commands:  arp(4), ifconfig(8), netstat(1)

Specifications:  RFC826.