rpc.ypxfrd(8)

1RPC.YPXFRD(8)                NIS Reference Manual                RPC.YPXFRD(8)
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NAME

6       rpc.ypxfrd - NIS map transfer server
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SYNOPSIS

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

14       rpc.ypxfrd is used for speed up the transfer of very large NIS maps
15       from a NIS master to the NIS slave server. If a NIS slave server
16       receives a message that there is a new map, it will start ypxfr for
17       transfering the new map.  ypxfr will read the contents of a map from
18       the master server using the yp_all() function.
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20       The rpc.ypxfrd server speeds up the transfer process by allowing NIS
21       slave servers to simply copy the master servers map files rather than
22       building their own from scratch.  rpc.ypxfrd uses an RPC-based file
23       transfer protocol.
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25       If the on-disk format of the database on both machines is not the same,
26       rpc.ypxfrd will refuse to send the data and ypxfr will fallback to
27       yp_all() and fetch every single entry alone.
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29       rpc.ypxfrd could be started by inetd. But since it starts very slowly,
30       it should be started after ypserv from /etc/init.d/ypxfrd.
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32       It is possible to pass OPTIONS to rpc.ypxfrd using the environment
33       variable YPXFRD_ARGS and this variable can be set in
34       /etc/sysconfig/network.
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OPTIONS

37       --debug
38           Causes the server to run in debugging mode. In debug mode, the
39           server does not background itself and prints extra status messages
40           to stderr for each request that it revceives.
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42       -d path
43           rpc.ypxfrd is using this directory instead of /var/yp.
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45       -p port
46           rpc.ypxfrd will bind itself to this port, which makes it possible
47           to have a router filter packets to the NIS ports. This can
48           restricted the access to the NIS server from hosts on the Internet.
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50       --version
51           Prints the version number
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SECURITY

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

63       The FreeBSD ypxfrd protocol is not compatible with that used by SunOS.
64       This is unfortunate but unavoidable: SUNs protocol is not freely
65       available, and even if it were it would probably not be useful since
66       the SunOS NIS v2 implementation uses the original ndbm package for its
67       map databases whereas the other implementation uses GNU DBM or Berkeley
68       DB. These packages uses vastly different file formats. Furthermore,
69       ndbm and gdbm are byte-order and word width sensitive and not very
70       smart about it, meaning that a gdbm or ndbm database created on a big
71       endian or 64bit system cannot be read on a little endian or 32bit
72       system. The FreeBSD ypxfrd protocol checks, if both, master and slave,
73       uses the same database packages and, if necessary, the byte order of
74       the system.
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FILES

77       /etc/ypserv.conf
78           Configuration file for options and access rights
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80       /var/yp/securenets
81           Configuration file for access rights
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83       /etc/sysconfig/network
84           Setting additional arguments to rpc.ypxfrd
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AUTHOR

90       ypxfrd protocol and FreeBSD Implementation: Bill Paul
91       <wpaul@ctr.columbia.edu>
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93       Linux Implementation: Thorsten Kukuk <kukuk@linux-nis.org>
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97NIS Reference Manual              07/20/2018                     RPC.YPXFRD(8)