-a                 Displays all of the current ARP entries.

    -d hostname        Deletes the entry for hostname if the user
                       issuing the command is a privileged user.

    -s hostname        Creates a single ARP entry for hostname. Use
    hardware_addr      of this flag requires privileges. Here:
    [temp] [pub]       hostname   Specifies the remote host
                                  identified by the entry.
                       hardware_  Specifies the hardware address
                       addr       of the remote host. The address
                                  is given as 6 hexadecimal bytes
                                  separated by colons.
                       temp       Specifies that this ARP table entry
                                  is temporary. When this argument
                                  is not used, the table entry is
                                  permanent.
                       pub        Indicates 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.

    [-u]               Displays the MAC address in noncanonical form
                       with address bytes reversed and separated by a
                       colon character (:). By default, all addresses
                       are displayed in canonical form with address
                       bytes separated by the hyphen character (-).

                       When used with the -s flag, this indicates
                       that the hardware_addr is in noncanonical
                       form.