arp(1M)                                                   arp(1M)



NAME
     arp - displays and modifies the address translation table

SYNOPSIS
     arp host

     arp -a [kernel] [memory-interface]

     arp -d host

     arp -f file

     arp -s host ethernet-address [status]

ARGUMENTS
     -a [kernel] [memory-interface]
          Displays all the entries in the address translation
          table.  The value of kernel specifies a kernel other
          than the default, /unix.  The value of memory-interface
          specifies a memory interface other than the default,
          /dev/kmem.

     -d host
          Deletes the entry specified by host.  See the host
          argument for an explanation of its value.  Only the
          system administrator can use this option.

     -f file
          Causes arp to read file and add the entries that file
          contains to the address resolution table.  Only the
          system administrator can use this option.

          The entries in file must be of this form:

             host ethernet-address [status]

          See the host argument for an explanation of its value.
          You specify ethernet-address as six hexadecimal bytes
          separated by a colon, such as:

             02:60:8c:05:c9:d3

          The value of status specifies a value for a flag that
          is set for the entry. If you do not specify status, the
          flag is set to indicate a permanent entry.  The status
          values are:

          temp Sets the flag to indicate a temporary entry.

          pub  Sets the flag to indicate a ``published'' entry;
               that is, the system acts as an Address Resolution
               Protocol (ARP) server by responding to resolution



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arp(1M)                                                   arp(1M)



               requests for addresses that are not its own.

          trail
               Sets the flag to indicate that the host supports
               ``trailer'' link-level encapsulation packets,
               which minimize the number of memory-to-memory copy
               operations performed by the receiver.

     host Specifies a host. The value of host can be a symbolic
          name, such as wolfie, or an Internet address, such as
          90.175.0.56.

     -s host ethernet-address [status]
          Creates an entry in the address translation table for
          the host specified by host.  Only the system
          administrator can use this option.

          See the host argument for an explanation of its value.
          See -f option for an explanation of ethernet-address
          and status.

DESCRIPTION
     arp displays and modifies the Internet-to-Ethernet address
     translation table used by the ARP.  If you do not specify
     any options, arp displays the current address translation
     table entry for host.

STATUS MESSAGES AND VALUES
     The arp command can produce these messages:

     bad line:line
          An entry in the file argument to the -f option has
          fewer than two fields.

     cannot openfile
          The value that you specified for file does not exist or
          is unreadable.

     can't get memory for arptab
          The arp command was unable to allocate enough memory to
          get a copy of the address translation table.

     error reading arptab
          The arp command was unable to read the address
          translation table.

     host: unknown host
          You have specified a host that is not present in the
          file /etc/hosts.

     invalid Ethernet address
          You have specified an Ethernet address that does not



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arp(1M)                                                   arp(1M)



          consist of six bytes separated by colons.

     kernel: bad namelist
          The arp command was unable to locate the address
          resolution table by using the value of kernel that you
          specified.

     kernel: namelist wrong
          The address translation table for the value of kernel
          that you specified is too small or too large.

     Network is unreachable
          You have specified a system that is not attached to
          your local network.

     Not owner
          You do not have permission modify the address
          translation table.

     Memory fault(coredump)
          You do not have permission to read /dev/kmem.  You
          should be root when you run arp.

LIMITATIONS
     An attempt to have more than eight permanent entries in the
     address translation table will fail if the entries hash to
     the same slot.

FILES
     /dev/kmem
          Default memory interface file
     /etc/arp
          Executable file
     /unix
          Default kernel file

SEE ALSO
     etheraddr(1M), ifconfig(1M)

     inet(3N), arp(5P) in A/UX Programmer's Reference















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