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