HOST.CONF(5)						    Linux System Administration 					      HOST.CONF(5)

NAME

       host.conf - resolver configuration file

DESCRIPTION

       The  file  /etc/host.conf contains configuration information specific to the resolver library.  It should contain one configuration keyword
       per line, followed by appropriate configuration information.  The keywords recognized are order, trim, multi, nospoof, and reorder.   These
       keywords are described below.

       order  This keyword specifies how host lookups are to be performed.  It should be followed by one or more lookup methods, separated by com-
	      mas.  Valid methods are bind, hosts, and nis.

       trim   This keyword may be listed more than once.  Each time it should be followed by a single domain name, with  the  leading  dot.   When
	      set,  the  resolv+  library  will  automatically	trim the given domain name from the end of any hostname resolved via DNS.  This is
	      intended for use with local hosts and domains.  (Related note: trim will not affect host- names gathered via NIS or the hosts  file.
	      Care  should  be	taken  to  ensure that the first hostname for each entry in the hosts file is fully qualified or non-qualified, as
	      appropriate for the local installation.)

       multi  Valid values are on and off.  If set to on, the resolv+ library will return all valid addresses for  a  host  that  appears  in  the
	      /etc/hosts  file,  instead  of only the first.  This is off by default, as it may cause a substantial performance loss at sites with
	      large hosts files.

       nospoof
	      Valid values are on and off.  If set to on, the resolv+ library will attempt to prevent hostname spoofing to enhance the security of
	      rlogin  and  rsh.   It  works  as  follows:  after performing a host address lookup, resolv+ will perform a hostname lookup for that
	      address.	If the two hostnames do not match, the query will fail.

       spoofalert
	      If this option is set to on and the nospoof option is also set, resolv+ will log a warning of the error  via  the  syslog  facility.
	      The default value is off.

       reorder
	      Valid  values  are  on  and off.	If set to on, resolv+ will attempt to reorder host addresses so that local addresses (i.e., on the
	      same subnet) are listed first when a gethostbyname(3) is performed.  Reordering is done for all lookup methods.  The  default  value
	      is off.

FILES

       /etc/host.conf
	      Resolver configuration file

       /etc/resolv.conf
	      Resolver configuration file

       /etc/hosts
	      Local hosts database

SEE ALSO

       gethostbyname(3), hostname(7), resolv+(8), named(8)

Debian GNU/Linux						    1997-01-02							      HOST.CONF(5)