NAME

       md_src_plugins_network_README - README

       • infos = Information about network plugin is in keys below

       • infos/author = Markus Raab elektra@libelektra.org

       • infos/licence = BSD

       • infos/needs =

       • infos/provides = check

       • infos/placements = presetstorage

       • infos/description = Checks keys if they contain a valid ip address

       This plugin is a check plugin that checks if a key contains a valid ip address. It uses
       the POSIX.1-2001 interface getaddrinfo() in order to check if an ip address is valid.

   Purpose
       While, in theory, a regular expression can express if a string is a network address, in
       practice, such an attempt does not work well. The reason is that an unmanageable number of
       valid shortenings for IPv6 addresses makes the regular expression hard to write and
       understand.

       So the idea of building such a complicated regular expression was discarded, but instead a
       dedicated checker was introduced. The idea is to use the operating system facilities to
       resolve the network address. If this succeeds, it is guaranteed that this network address
       will be valid when it is resolved by the same interface afterwards.

       Many network address translators coexist. In POSIX.1-2001 a powerful address translator is
       provided with the interface getaddrinfo(). It is a common network address translation for
       both IPv4 and IPv6. We used it to implement this plugin.