host
    Optional. Default: All hosts.
    All alias names for the specified host are displayed.
    o  If a host has more than one IP address and you specify the
       name, all its addresses and aliases are displayed.
    o  If a host has multiple IP addresses and you specify an alias
       that is defined on multiple IP addresses, only the first IP
       address and aliases are displayed.
    o  If you do not specifiy the host parameter or if you use a
       wildcard, all hosts from the local and BIND databases are
       displayed.
    o  If you use a wildcard to complete a host name, no BIND
       information is displayed.
    o  If you specify a host, entries are displayed first from the
       local hosts database, if they exist; otherwise, entries from
       the BIND database are displayed, if they exist.