.. _manual-about:

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 About NSClient++
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NSClient++ (nscp) aims to be a simple yet powerful and secure monitoring daemon. It was built for Nagios/Icinga, but nothing in the daemon is Nagios/Icinga specific and it can be used in many other scenarios where you want to receive/distribute check metrics.

The deamon has 3 main functions:

#. Allow a remote machine (monitoring server) to request commands to be run on this machine (the monitored machine) which return the status of the machine.
#. Submit the same results to a remote (monitoring server).
#. Take action and perform tasks.

Extending NSClient++
====================

NSClient++ is designed to be open ended and allow you to customize it in any way you design thus extensibility is a core feature.


* ExternalScripts responds to queries and are executed by the operating system and the results are returned as-is.
   This is generally the simplest way to extend NSClient++ as you can utilize whatever infrastructure or skill set you already have.

* LuaScripts are internal scripts which runs inside NSClient++ and performs various tasks and/or responds to queries.
   This is the best option if you want to allow the script to run on any platform with as little infrastructure as possible.

* PythonScripts are internal scripts which runs inside NSClient++ and performs various tasks and/or responds to queries.
   Python is an easy and powerful language but it requires you to also install python which is often not possible on server hardware.

* .Net modules similar to Native modules below but written on the dot-net platform.
   This allows you to write components on top of the large dot-net ecosystem.

* Modules are native plugins which can extend NSClient++ in pretty much any way possible.
   This is probably the most complicated way but gives you the most power and control.

Talking to NSClient++
=====================

Since NSClient++ is meaningless by itself it also supports a lot of protocols to allow it to be used by a lot of monitoring solutions.

* NRPE (Nagios Remote plugin Executor) is a Nagios centric protocol to collect remote metrics.
* NSCA (Nagios Service Check Acceptor) is a Nagios centric protocol for submitting results.
* NSCP is the native NSClient++ protocol (still under development)
* dNSCP is a high performance distributed version of NSCP for high volume traffic.
* NRDP is a replacement for NSCA.
* check_mk is a protocol utilized by the check_mk monitoring system.
* Syslog is a protocol primarily designed for submitting log records.
* Graphite allows you do real-time graphing.
* SMTP is more of a toy currently.

Supported OS/Platform
=====================

NSClient++ should run on the following operating systems:

* Windows: From NT4 SP5 up to Windows 2008 and Windows 7
* Linux: Debian, Centos and Ubuntu (and possibly others as well)
* Win32, x64 as well as various Linux hardware as well.
