.\"	$NetBSD: ypserv.8,v 1.22 2011/04/25 22:53:09 wiz Exp $
.\"
.\" Copyright (c) 1994 Mats O Jansson <moj@stacken.kth.se>
.\" All rights reserved.
.\"
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.\" modification, are permitted provided that the following conditions
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.Dd May 20, 2006
.Dt YPSERV 8
.Os
.Sh NAME
.Nm ypserv
.Nd NIS server daemon
.Sh SYNOPSIS
.Nm
.Op Fl dfl
.Op Fl p Ar port
.Sh DESCRIPTION
.Nm
is a fundamental part of the network information system called
.Tn NIS .
This server provides information from
.Tn NIS
maps to the
.Tn NIS
clients on the network.
.Pp
A
.Tn NIS
map is stored on the server as a
.Xr db 3
database.
A number of
.Tn NIS
maps is grouped together in a domain.
.Nm
determines the domains it serves by looking for a directory with
the domain name in
.Ar /var/yp .
.Pp
In an effort to improve the security of
.Tn NIS
(which has, historically, not been very good), this
.Nm
has support for libwrap-based access control.
See
.Xr hosts_access 5
for more information.
The
.Em daemon
used for access control is the name which
.Nm
was invoked as (typically
.Dq ypserv ) .
If a host is not allowed to query this
.Tn NIS
server,
.Nm
will return the
.Tn NIS
result code YP_NODOM.
To avoid problems with DNS lookups causing
.Nm
to hang,
.Nm
disables DNS lookups for its client
.Xr hosts_access 5
lists.
The result is that
.Nm
can only use address based patterns.
This also means that wildcard patterns such as LOCAL or KNOWN will
not work.
.Pp
The process pid of the
.Nm
process can be found in the file
.Pa /var/run/ypserv.pid .
.Pp
The options are as follows:
.Bl -tag -width indent
.It Fl d
Use internet Domain Name System.
If a query to map
.Pa hosts.byname
or
.Pa hosts.byaddr
fails, make a DNS query and return the result if successful.
.It Fl f
Run in the foreground.
.It Fl l
Enable logging of all requests.
.It Fl p Ar port
Bind to the specified
.Ar port
instead of dynamically allocating one.
.El
.Pp
All messages are sent to the system log with the facility
.Dv LOG_DAEMON .
Error messages have the priority
.Dv LOG_ERR .
Refused requests are logged with the priority
.Dv LOG_WARNING .
All other messages are logged with the priority
.Dv LOG_INFO .
.Sh FILES
.Bl -tag -width /var/run/ypserv.pid -compact
.It Pa /var/run/ypserv.pid
.El
.Sh SEE ALSO
.Xr syslog 3 ,
.Xr hosts_access 5 ,
.Xr nis 8 ,
.Xr syslogd 8 ,
.Xr ypbind 8 ,
.Xr ypinit 8
.Sh AUTHORS
This implementation of
.Nm
was originally written by
.An Mats O Jansson
.Aq moj@stacken.kth.se .
The access control code was later re-written from scratch by
.An Jason R. Thorpe
.Aq thorpej@NetBSD.org .