Free Knowledge Resources


Linux Manual Pages


Free Software * Books

Source Code

Free Media

Linux

nss-myhostname(8)


NAME

   nss-myhostname, libnss_myhostname.so.2 - Provide hostname resolution
   for the locally configured system hostname.

SYNOPSIS

   libnss_myhostname.so.2

DESCRIPTION

   nss-myhostname is a plug-in module for the GNU Name Service Switch
   (NSS) functionality of the GNU C Library (glibc), primarily providing
   hostname resolution for the locally configured system hostname as
   returned by gethostname(2). The precise hostnames resolved by this
   module are:

   *   The local, configured hostname is resolved to all locally
       configured IP addresses ordered by their scope, or --- if none are
       configured --- the IPv4 address 127.0.0.2 (which is on the local
       loopback) and the IPv6 address ::1 (which is the local host).

   *   The hostnames "localhost" and "localhost.localdomain" (as well as
       any hostname ending in ".localhost" or ".localhost.localdomain")
       are resolved to the IP addresses 127.0.0.1 and ::1.

   *   The hostname "gateway" is resolved to all current default routing
       gateway addresses, ordered by their metric. This assigns a stable
       hostname to the current gateway, useful for referencing it
       independently of the current network configuration state.

   Various software relies on an always-resolvable local hostname. When
   using dynamic hostnames, this is traditionally achieved by patching
   /etc/hosts at the same time as changing the hostname. This is
   problematic since it requires a writable /etc file system and is
   fragile because the file might be edited by the administrator at the
   same time. With nss-myhostname enabled, changing /etc/hosts is
   unnecessary, and on many systems, the file becomes entirely optional.

   To activate the NSS modules, add "myhostname" to the line starting with
   "hosts:" in /etc/nsswitch.conf.

   It is recommended to place "myhostname" last in the nsswitch.conf'
   "hosts:" line to make sure that this mapping is only used as fallback,
   and that any DNS or /etc/hosts based mapping takes precedence.

EXAMPLE

   Here is an example /etc/nsswitch.conf file that enables nss-myhostname
   correctly:

       passwd:         compat mymachines systemd
       group:          compat mymachines systemd
       shadow:         compat

       hosts:          files mymachines resolve [!UNAVAIL=return] dns myhostname
       networks:       files

       protocols:      db files
       services:       db files
       ethers:         db files
       rpc:            db files

       netgroup:       nis

   To test, use glibc's getent tool:

       $ getent ahosts `hostname`
       ::1       STREAM omega
       ::1       DGRAM
       ::1       RAW
       127.0.0.2       STREAM
       127.0.0.2       DGRAM
       127.0.0.2       RAW

   In this case, the local hostname is omega.

SEE ALSO

   systemd(1), nss-systemd(8), nss-resolve(8), nss-mymachines(8),
   nsswitch.conf(5), getent(1)



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.


birds banner