1RPC.YPXFRD(8) NIS Reference Manual RPC.YPXFRD(8)
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6 rpc.ypxfrd - NIS map transfer server
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9 /usr/sbin/rpc.ypxfrd [-d path] [-p port] [--debug]
10 /usr/sbin/rpc.ypxfrd --version
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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.
19 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.
24 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.
28 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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33 --debug
34 Causes the server to run in debugging mode. In debug mode, the
35 server does not background itself and prints extra status messages
36 to stderr for each request that it revceives.
37 -d path
39 rpc.ypxfrd is using this directory instead of /var/yp.
40 -p port
42 rpc.ypxfrd will bind itself to this port, which makes it possible
43 to have a router filter packets to the NIS ports. This can
44 restricted the access to the NIS server from hosts on the Internet.
45 --version
47 Prints the version number
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50 rpc.ypxfrd uses the same functions for checking a host as ypserv. At
51 first, rpc.ypxfrd will check a request from an address with
52 /var/yp/securenets or the tcp wrapper. If the host is allowed to
53 connect to the server, rpc.ypxfrd will uses the rules from
54 /etc/ypserv.conf to check the requested map. If a mapname doesn't match
55 a rule, rpc.ypxfrd will look for the YP_SECURE key in the map. If it
56 exists, rpc.ypxfrd will only allow requests on a reserved port.
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59 The FreeBSD ypxfrd protocol is not compatible with that used by SunOS.
60 This is unfortunate but unavoidable: SUNs protocol is not freely
61 available, and even if it were it would probably not be useful since
62 the SunOS NIS v2 implementation uses the original ndbm package for its
63 map databases whereas the other implementation uses GNU DBM or Berkeley
64 DB. These packages uses vastly different file formats. Furthermore,
65 ndbm and gdbm are byte-order and word width sensitive and not very
66 smart about it, meaning that a gdbm or ndbm database created on a big
67 endian or 64bit system cannot be read on a little endian or 32bit
68 system. The FreeBSD ypxfrd protocol checks, if both, master and slave,
69 uses the same database packages and, if necessary, the byte order of
70 the system.
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73 /etc/ypserv.conf
74 Configuration file for options and access rights
75 /var/yp/securenets
77 Configuration file for access rights
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80 ypserv(8), makedbm(8), yppush(8), ypxfr(8)
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83 ypxfrd protocol and FreeBSD Implementation: Bill Paul
84 <wpaul@ctr.columbia.edu>
85 Linux Implementation: Thorsten Kukuk <kukuk@linux-nis.org>
87NIS Reference Manual 05/14/2019 RPC.YPXFRD(8)