ypserv.conf(5)
NAME
ypserv.conf - configuration file for ypserv and rpc.ypxfrd
DESCRIPTION
ypserv.conf is an ASCII file which contains some options for ypserv. It
also contains a list of rules for special host and map access for
ypserv and rpc.ypxfrd. This file will be read by ypserv and rpc.ypxfrd
at startup, or when receiving a SIGHUP signal.
There is one entry per line. If the line is a option line, the format
is:
option: <argument>
The line for an access rule has the format:
host:domain:map:security
All rules are tried one by one. If no match is found, access to a map
is allowed.
Following options exist:
files: 30
This option specifies, how many database files should be cached
by ypserv. If 0 is specified, caching is disabled. Decreasing
this number is only possible, if ypserv is restarted.
trusted_master: server
When a map is pushed to a slave, the slave normally only accepts
updates to existing maps, and then only from the real master.
If this option is set on a slave server, new (not yet existing)
maps from the host server will be accepted. The default is that
no trusted master is set and new maps will not be accepted.
Example:
trusted_master: ypmaster.example.org
slp: [yes|<no>|domain]
If this option is enabled and SLP support compiled in, the NIS
server registers itself on a SLP server. If the variable is set
to domain, an attribute domain with a comma seperated list of
supported domainnames is set. Else this attribute will not be
set.
xfr_check_port: [<yes>|no]
With this option enabled, the NIS master server has to run on a
priviliged port (< 1024). The default is "yes" (enabled).
The field descriptions for the access rule lines are:
host IP address. Wildcards are allowed.
Examples:
131.234. = 131.234.0.0/255.255.0.0
131.234.214.0/255.255.254.0
domain specifies the domain, for which this rule should be applied. An
asterix as wildcard is allowed.
map name of the map, or asterisk for all maps.
security
one of none, port, deny:
none always allow access.
port allow access if the client request originates from a priviliged
port (< 1024). Otherwise do not allow access.
deny deny access to this map.
You can add /mangle:field to the none or port security keywords. The
:field part is optional. It will replace field number field (the
default is 2, the password field of the passwd and shadow maps) with
the value x for client requests from non-priviliged ports (>= 1024) for
the port security keyword and in all cases for the none security
keyword.
FILES
/etc/ypserv.conf
SEE ALSO
ypserv(8), rpc.ypxfrd(8)
WARNINGS
The access rules for special maps are no real improvement in security, but they make the life a little bit harder for a potential hacker.
BUGS
Solaris clients don't use privileged ports. All security options that depend on privileged ports cause big problems on Solaris clients.
AUTHOR
Thorsten Kukuk <kukuk@suse.de>
Opportunity
Personal Opportunity - Free software gives you access to billions of dollars of software at no cost. Use this software for your business, personal use or to develop a profitable skill. Access to source code provides access to a level of capabilities/information that companies protect though copyrights. Open source is a core component of the Internet and it is available to you. Leverage the billions of dollars in resources and capabilities to build a career, establish a business or change the world. The potential is endless for those who understand the opportunity.
Business Opportunity - Goldman Sachs, IBM and countless large corporations are leveraging open source to reduce costs, develop products and increase their bottom lines. Learn what these companies know about open source and how open source can give you the advantage.
Free Software
Free Software provides computer programs and capabilities at no cost but more importantly, it provides the freedom to run, edit, contribute to, and share the software. The importance of free software is a matter of access, not price. Software at no cost is a benefit but ownership rights to the software and source code is far more significant.
Free Office Software - The Libre Office suite provides top desktop productivity tools for free. This includes, a word processor, spreadsheet, presentation engine, drawing and flowcharting, database and math applications. Libre Office is available for Linux or Windows.
Free Books
The Free Books Library is a collection of thousands of the most popular public domain books in an online readable format. The collection includes great classical literature and more recent works where the U.S. copyright has expired. These books are yours to read and use without restrictions.
Source Code - Want to change a program or know how it works? Open Source provides the source code for its programs so that anyone can use, modify or learn how to write those programs themselves. Visit the GNU source code repositories to download the source.
Education
Study at Harvard, Stanford or MIT - Open edX provides free online courses from Harvard, MIT, Columbia, UC Berkeley and other top Universities. Hundreds of courses for almost all major subjects and course levels. Open edx also offers some paid courses and selected certifications.
Linux Manual Pages - A man or manual page is a form of software documentation found on Linux/Unix operating systems. Topics covered include computer programs (including library and system calls), formal standards and conventions, and even abstract concepts.
