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       ypserv.conf - configuration file for ypserv and rpc.ypxfrd


       ypserv.conf is an ASCII file which contains some options for ypserv. It
       also contains a list of rules for  special  host  and  map  access  for
       ypserv  and rpc.ypxfrd. This file will be read by ypserv and rpc.ypxfrd
       at startup, or when receiving a SIGHUP signal.

       There is one entry per line. If the line is a option line,  the  format

              option: <argument>

       The line for an access rule has the format:


       All  rules  are tried one by one. If no match is found, access to a map
       is allowed.

       Following options exist:

       files: 30
              This option specifies, how many database files should be  cached
              by  ypserv.   If 0 is specified, caching is disabled. Decreasing
              this number is only possible, if ypserv is restarted.

       trusted_master: server
              When a map is pushed to a slave, the slave normally only accepts
              updates  to  existing  maps, and then only from the real master.
              If this option is set on a slave server, new (not yet  existing)
              maps  from the host server will be accepted. The default is that
              no trusted master is set and new maps will not be accepted.

       slp: [yes|<no>|domain]
              If this option is enabled and SLP support compiled in,  the  NIS
              server  registers itself on a SLP server. If the variable is set
              to domain, an attribute domain with a comma  seperated  list  of
              supported  domainnames  is  set. Else this attribute will not be

       xfr_check_port: [<yes>|no]
              With this option enabled, the NIS master server has to run on  a
              priviliged port (< 1024). The default is "yes" (enabled).

       The field descriptions for the access rule lines are:

       host   IP address. Wildcards are allowed.
              131.234. =

       domain specifies  the domain, for which this rule should be applied. An
              asterix as wildcard is allowed.

       map    name of the map, or asterisk for all maps.

              one of none, port, deny:

       none   always allow access.

       port   allow access if the client request originates from a  priviliged
              port (< 1024). Otherwise do not allow access.

       deny   deny access to this map.

       You  can  add  /mangle:field to the none or port security keywords. The
       :field part is optional.  It  will  replace  field  number  field  (the
       default  is  2,  the password field of the passwd and shadow maps) with
       the value x for client requests from non-priviliged ports (>= 1024) for
       the  port  security  keyword  and  in  all  cases for the none security




       ypserv(8), rpc.ypxfrd(8)


       The access rules for special maps are no real improvement in  security,
       but they make the life a little bit harder for a potential hacker.


       Solaris  clients  don’t use privileged ports. All security options that
       depend on privileged ports cause big problems on Solaris clients.


       Thorsten Kukuk <>