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YPSERV(8)                   System Manager's Manual                  YPSERV(8)

     ypserv - NIS server daemon

     ypserv [-dfl] [-p port]

     ypserv is a fundamental part of the network information system called
     NIS.  This server provides information from NIS maps to the NIS clients
     on the network.

     A NIS map is stored on the server as a db(3) database.  A number of NIS
     maps is grouped together in a domain.  ypserv determines the domains it
     serves by looking for a directory with the domain name in /var/yp.

     In an effort to improve the security of NIS (which has, historically, not
     been very good), this ypserv has support for libwrap-based access
     control.  See hosts_access(5) for more information.  The daemon used for
     access control is the name which ypserv was invoked as (typically
     "ypserv").  If a host is not allowed to query this NIS server, ypserv
     will return the NIS result code YP_NODOM.  To avoid problems with DNS
     lookups causing ypserv to hang, ypserv disables DNS lookups for its
     client hosts_access(5) lists.  The result is that ypserv can only use
     address based patterns.  This also means that wildcard patterns such as
     LOCAL or KNOWN will not work.

     The process pid of the ypserv process can be found in the file

     The options are as follows:

     -d      Use internet Domain Name System.  If a query to map hosts.byname
             or hosts.byaddr fails, make a DNS query and return the result if

     -f      Run in the foreground.

     -l      Enable logging of all requests.

     -p port
             Bind to the specified port instead of dynamically allocating one.

     All messages are sent to the system log with the facility LOG_DAEMON.
     Error messages have the priority LOG_ERR.  Refused requests are logged
     with the priority LOG_WARNING.  All other messages are logged with the
     priority LOG_INFO.


     syslog(3), hosts_access(5), nis(8), syslogd(8), ypbind(8), ypinit(8)

     This implementation of ypserv was originally written by Mats O Jansson
     <moj@stacken.kth.se>.  The access control code was later re-written from
     scratch by
     Jason R. Thorpe <thorpej@NetBSD.org>.

NetBSD 10.99                     May 20, 2006                     NetBSD 10.99