Section: Reference Manual (8)
Updated: August 2001
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rpc.ypxfrd - NIS map transfer server
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
for transfering the new map.
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.
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.
uses an RPC-based file transfer protocol, so that there is no need
for building a new map.
could be started by inetd. But since it starts very slowly,
it should be started after
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
is using this directory instead of /var/yp
- -p port
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.
Prints the version number
uses the same functions for checking a host as
will check a request from an address with
or the tcp wrapper.
If the host is allowed to connect to the server,
will uses the rules from
to check the requested map. If a mapname doesn't match a rule,
will look for the YP_SECURE key in the map. If it exists,
will only allow requests on a reserved port.
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
protocol checks, if both, master and slave, uses the same database packages
and, if necessary, the byte order of the system.
ypxfrd protocol and FreeBSD Implementation: Bill Paul <email@example.com>
Linux Implementation: Thorsten Kukuk <firstname.lastname@example.org>
- SEE ALSO
linux.jgfs.net manual pages