RPC.YPXFRD(8)							 Reference Manual						     RPC.YPXFRD(8)

NAME

       rpc.ypxfrd - NIS map transfer server

SYNOPSIS

       /usr/sbin/rpc.ypxfrd [ -d path ] [ -p port ] [ --debug ]
       /usr/sbin/rpc.ypxfrd --version

DESCRIPTION

       rpc.ypxfrd  is  used  for  speed  up  the transfer of very large NIS maps from a NIS master to the NIS slave server. If a  NIS slave server
       receives a message that there is a new map, it will start ypxfr for transfering the new map.  ypxfr will read the contents of  a  map  from
       the master server using the yp_all() function. This process can take several minutes when there are very large maps which have to be stored
       by the database library.

       The rpc.ypxfrd server speeds up the transfer process by allowing NIS slave servers to simply copy the master server's map files rather than
       building their own from scratch.  rpc.ypxfrd uses an RPC-based file transfer protocol, so that there is no need for building a new map.

       rpc.ypxfrd could be started by inetd. But since it starts very slowly, it should be started after ypserv from /etc/init.d/ypxfrd.

OPTIONS

       --debug
	      Causes the server to run in debugging mode. In debug mode, the server does not background itself and prints extra status messages to
	      stderr for each request that it revceives.

       -d directory
	      rpc.ypxfrd is using this directory instead of /var/yp

       -p port
	      rpc.ypxfrd will bind itself to this port, which makes it possible to have a router  filter  packets  to  the  NIS  ports.  This  can
	      restricted the access to the NIS server from hosts on the Internet.

       --version
	      Prints the version number

SECURITY

       rpc.ypxfrd  uses  the  same  functions  for  checking  a  host  as  ypserv.  At first, rpc.ypxfrd will check a request from an address with
       /var/yp/securenets or the tcp wrapper.  If  the	host  is  allowed  to  connect	to  the  server,  rpc.ypxfrd  will  uses  the  rules  from
       /etc/ypserv.conf  to  check the requested map. If a mapname doesn't match a rule, rpc.ypxfrd will look for the YP_SECURE key in the map. If
       it exists, rpc.ypxfrd will only allow requests on a reserved port.

FILES

       /etc/ypserv.conf /var/yp/securenets

SEE ALSO

       ypserv(8), makedbm(8), yppush(8), ypxfr(8)

BUGS

       The FreeBSD ypxfrd protocol is not compatible with that used by SunOS. This is unfortunate but unavoidable: Sun's protocol  is  not  freely
       available, and even if it were it would probably not be useful since the SunOS NIS v2 implimentation uses the original ndbm package for its
       map databases whereas the other implimentation uses GNU DBM or Berkeley DB. These packages uses vastly different file formats. Furthermore,
       ndbm  and  gdbm	are  byte-order sensitive and not very smart about it, meaning that a gdbm or ndbm database created on a big endian system
       can't be read on a little endian system. The FreeBSD ypxfrd protocol checks, if both, master and slave, uses  the  same	database  packages
       and, if necessary, the byte order of the system.

AUTHOR

       ypxfrd protocol and FreeBSD Implementation: Bill Paul <wpaul@ctr.columbia.edu>
       Linux Implementation: Thorsten Kukuk <kukuk@suse.de>

YP Server							    August 2001 						     RPC.YPXFRD(8)