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: src/usr.sbin/rpc.ypxfrd/rpc.ypxfrd.8,v 1.9.2.3 2003/03/11 22:31:32 trhodes Exp $ 32.\" $DragonFly: src/usr.sbin/rpc.ypxfrd/rpc.ypxfrd.8,v 1.7 2008/11/23 21:55:52 swildner Exp $ 33.\" 34.Dd June 2, 1996 35.Dt RPC.YPXFRD 8 36.Os 37.Sh NAME 38.Nm rpc.ypxfrd 39.Nd "NIS map transfer server" 40.Sh SYNOPSIS 41.Nm 42.Op Fl p Ar path 43.Sh DESCRIPTION 44The 45.Nm 46utility is used to speed up the distribution of very large NIS maps 47from NIS master to NIS slave servers. 48The normal method for transferring 49maps involves several steps: 50.Bl -bullet -offset indent 51.It 52The master server calls 53.Xr yppush 8 54to inform the slave servers to start a transfer. 55.It 56The slave servers invoke 57.Xr ypxfr 8 , 58which reads the entire contents of a map from the master server 59using the 60.Fn yp_all 61function. 62.It 63The 64.Xr ypxfr 8 65program then creates a new map database file by using the 66.Xr db 3 67library hash method to store the data that it receives from the server. 68.It 69When all the data has been retrieved, 70.Xr ypxfr 8 71moves the new file into place and sends 72.Xr ypserv 8 73on the local machine a YPPROC_CLEAR to tell it to refresh its 74database handles. 75.El 76.Pp 77This process can take several minutes when there are very large 78maps involved. 79For example: a passwd database with several tens of 80thousands of entries can consume several megabytes of disk space, 81and it can take the 82.Xr db 3 83library package a long time to sort and store all the records 84in a hash database. 85Consider also that there are two sets of map 86files: 87.Pa master.passwd.by{name,uid} 88and 89.Pa passwd.by{name,uid} . 90.Pp 91The 92.Nm 93utility speeds up the transfer process by allowing NIS slave servers to 94simply copy the master server's map files rather than building their 95own from scratch. 96Simply put, 97.Nm 98implements an RPC-based file transfer protocol. 99Transferring even 100a multi-megabyte file in this fashion takes only a few seconds compared 101to the several minutes it would take even a reasonably fast slave server 102to build a new map from scratch. 103.Pp 104The 105.Nm 106utility uses the same access restriction mechanism as 107.Xr ypserv 8 . 108This means that slave servers will only be permitted to transfer 109files if the rules in the 110.Pa securenets 111database permit it (see 112.Xr ypserv 8 113for more information on 114.Pa securenets ) . 115Furthermore, only slave servers using reserved 116ports will be allowed to transfer the 117.Pa master.passwd 118maps. 119.Sh OPTIONS 120The following option is available: 121.Bl -tag -width indent 122.It Fl p Ar path 123This option can be used to override the default path to 124the location of the NIS 125map databases. 126The compiled-in default path is 127.Pa /var/yp . 128.El 129.Sh FILES 130.Bl -tag -width Pa -compact 131.It Pa /var/yp/[domainname]/[maps] 132The NIS maps for a particular NIS domain. 133.El 134.Sh SEE ALSO 135.Xr yp 8 , 136.Xr yppush 8 , 137.Xr ypserv 8 , 138.Xr ypxfr 8 139.Sh AUTHORS 140.An Bill Paul Aq wpaul@ctr.columbia.edu 141.Sh BUGS 142The 143.Dx 144.Nm ypxfrd 145protocol is not compatible with that used by SunOS. 146This is unfortunate 147but unavoidable: Sun's protocol is not freely available, and even if it 148were it would probably not be useful since the SunOS NIS v2 implementation 149uses the original ndbm package for its map databases whereas the 150.Dx 151implementation uses Berkeley DB. 152These two packages use vastly different 153file formats. 154Furthermore, ndbm is byte-order sensitive and not very 155smart about it, meaning that am ndbm database created on a big endian 156system can't be read on a little endian system. 157