YPSERV(8) OpenBSD System Manager's Manual YPSERV(8)
ypserv - YP server daemon
ypserv [-1] [-a aclfile] [-d] [-x]
ypserv is a fundamental part of the network information system called YP.
This server provides information from YP maps to the YP clients on the
A YP map is stored on the server as a db(3) database. A number of YP
maps are grouped together in a domain. ypserv determines the domains it
serves by looking for a directory with the domain name in /var/yp.
YP hasn't been known for high security through the years. In recent
years security has improved by restricting access to the server. In
SunOS 4.1 has a new file occurred named /var/yp/securenet. It contains
networks the server can assume is secure. For information about the file
format, see securenet(5).
Before the author of this server had seen securenet(5) another format,
ypserv.acl(5), was implemented. This file format makes it possible to
allow and deny hosts and networks access to the server. This file can
have any name since it's given by the argument to -a (use full path).
The file used can be reread by sending a SIGHUP to ypserv. The process
PID can be found in the file /var/run/ypserv.pid.
If a host isn't secure all queries to the server will result in a
If the file /var/yp/ypserv.log exists then messages will be written to
If a directory named the same as the system domainname exists in /var/yp
(i.e., the domainname is ``foo'' and the directory /var/yp/foo exists),
then ypserv will be automatically started at boot time.
The options are as follows:
-1 Allow ypserv to answer old YP version 1 requests.
Don't use /var/yp/securenet. Use another file with a different
file format. For further information see ypserv.acl(5).
-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 successful. Alternately, if these maps were
built on the YP master using makedbm -b then DNS queries will be
done without needing to specify -d.
-x Terminate the server after processing aclfile or
securenet(5), ypserv.acl(5), yp(8), ypbind(8)
Mats O Jansson <mojATstacken.se>
OpenBSD 3.6 June 27, 1994 2