1.\" Copyright (c) 1995, 1996 2.\" Bill Paul <wpaul@ctr.columbia.edu>. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 3. All advertising materials mentioning features or use of this software 13.\" must display the following acknowledgement: 14.\" This product includes software developed by Bill Paul. 15.\" 4. Neither the name of the author nor the names of contributors 16.\" may be used to endorse or promote products derived from this software 17.\" without specific prior written permission. 18.\" 19.\" THIS SOFTWARE IS PROVIDED BY Bill Paul AND CONTRIBUTORS ``AS IS'' AND 20.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22.\" ARE DISCLAIMED. IN NO EVENT SHALL Bill Paul OR CONTRIBUTORS BE LIABLE 23.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29.\" SUCH DAMAGE. 30.\" 31.\" $FreeBSD$ 32.\" 33.Dd June 2, 1996 34.Dt RPC.YPXFRD 8 35.Os 36.Sh NAME 37.Nm rpc.ypxfrd 38.Nd "NIS map transfer server" 39.Sh SYNOPSIS 40.Nm rpc.ypxfrd 41.Op Fl p Ar path 42.Sh DESCRIPTION 43The 44.Nm 45daemon is used to speed up the distribtion of very large NIS maps 46from NIS master to NIS slave servers. The normal method for transfering 47maps involves several steps: 48.Bl -bullet -offset indent 49.It 50The master server calls 51.Xr yppush 8 52to inform the slave servers to start a transfer. 53.It 54The slave servers invoke 55.Xr ypxfr 8 , 56which reads the entire contents of a map from the master server 57using the yp_all() function. 58.It 59The 60.Xr ypxfr 8 61program then creates a new map database file by using the 62.Xr db 3 63library hash method to store the data that it receives from the server. 64.It 65When all the data has been retrieved, 66.Xr ypxfr 8 67moves the new file into place and sends 68.Xr ypserv 8 69on the local machine a YPPROC_CLEAR to tell it to refresh its 70database handles. 71.El 72.Pp 73This process can take several minutes when there are very large 74maps involved. For example: a passwd database with several tens of 75thousands of entries can consume several megabytes of disk space, 76and it can take the 77.Xr db 3 78library package a long time to sort and store all the records 79in a hash database. Consider also that there are two sets of map 80files: 81.Pa master.passwd.by{name,uid} 82and 83.Pa passwd.by{name,uid} . 84.Pp 85The 86.Nm 87server speeds up the transfer process by allowing NIS slave servers to 88simply copy the master server's map files rather than building their 89own from scratch. Simply put, 90.Nm 91implements an RPC-based file transfer protocol. Transfering even 92a multi-megabyte file in this fashion takes only a few seconds compared 93to the several minutes it would take even a reasonably fast slave server 94to build a new map from scratch. 95.Pp 96The 97.Nm 98server uses the same access restriction mechanism as 99.Xr ypserv 8 . 100This means that slave servers will only be permitted to transfer 101files if the rules in the 102.Xr securenets 5 103database permit it. Furthermore, only slave servers using reserved 104ports will be allowed to transfer the 105.Pa master.passwd 106maps. 107.Sh OPTIONS 108The following option is available: 109.Bl -tag -width indent 110.It Fl p Ar path 111This option can be used to override the default path to 112the location of the NIS 113map databases. The compiled-in default path is 114.Pa /var/yp . 115.El 116.Sh FILES 117.Bl -tag -width Pa -compact 118.It Pa /var/yp/[domainname]/[maps] 119The NIS maps for a particular NIS domain. 120.El 121.Sh SEE ALSO 122.Xr yp 4 , 123.Xr yppush 8 , 124.Xr ypserv 8 , 125.Xr ypxfr 8 126.Sh BUGS 127The 128.Bx Free 129.Nm ypxfrd 130protocol is not compatible with that used by SunOS. This is unfortunate 131but unavoidable: Sun's protocol is not freely available, and even if it 132were it would probably not be useful since the SunOS NIS v2 implementation 133uses the original ndbm package for its map databases whereas the 134.Bx Free 135implementation uses Berkeley DB. These two packages use vastly different 136file formats. Furthermore, ndbm is byte-order sensitive and not very 137smart about it, meaning that am ndbm database created on a big endian 138system can't be read on a little endian system. 139.Sh AUTHORS 140.An Bill Paul Aq wpaul@ctr.columbia.edu 141