- NetBSD Manual Pages
YPSERV(8) NetBSD System Manager's Manual YPSERV(8)
Powered by man-cgi (2021-03-02).
Maintained for NetBSD
by Kimmo Suominen.
Based on man-cgi by Panagiotis Christias.
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 con-
trol. 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.
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
syslog(3), hosts_access(5), nis(8), syslogd(8), ypbind(8), ypinit(8)
This implementation of ypserv was originally written by Mats O Jansson
<firstname.lastname@example.org>. The access control code was later re-written from
Jason R. Thorpe <thorpej@NetBSD.org>.
NetBSD 5.0.1 May 20, 2006 NetBSD 5.0.1