A tutorial for writing a quick and simple Lua script which will turn check_cpu into a multi functional check which return top CPU consumers. In last weeks edition I introduced the various parts we need to make this a reality. And that idea I have with NSClient++ is to create a Lego box with small multi purpose functions which the users can combine in many different ways. Here I will show you how we can do that.

An often requested feature is to include the top-5 consumers of high CPU load in the result from check_cpu (or checkCpu). I have often discarded this as a non-core feature since it is not something I think should be part of NSClient++ instead I think it should be a script. Since no-one has created such a script I figured it would make a nice blog post so here I describe in a step by step guide how to create such a script for NSClient++.

The biggest reason for Nagios success is the ability to extend it with custom scripts which makes it one of the most powerful monitoring systems. Now Nagios is not the only place where you can extend your monitoring! NSClient++ provides many ways to extend it with scripts and since I have gotten many questions about how to use scripts with NSClient++ lately I have decided to write this tutorial to help sort out the concepts.

Stateful scripts are a simple yet powerfully way to enhance your monitoring which I think is used far to little. Using stateful script you can easily add simple predictions and change management. This is very easy to accomplished using NSClient++ as its built-in scripting modules by default provides stateful scripts (in contrast to Nagios and Icinga which tends to be stateless). This tutorial will walk you through writing a simple stateful script in Lua. If you are still confused about stateful scripts the main benefit is that they remember things. Thus you can alert when something changes as well as predict the future. A good example of this is disk growth prediction but there are a lot of other scenarios where they are useful.

Take your monitoring to the next level by creating self-resetting event log checks. Sometimes it is not only faults which can be harvested from the windows event log many applications will also report a message when the state returns to normal. This tutorial show you how to configure NSClient++ 0.4.1 to setup auto resetting event log checks. In addition to using passive checks via NSCA I will also demonstrate how to use the Cache module to benefit from real time event log checks via NRPE.

This is a series detailing how you can leverage WMI to monitor you Computers from a monitoring tool such as Nagios or Icinga. Since I decided to clean up the command line syntax of the WMI plugin for NSClient++ for the up-coming 0.4.0 version a few days ago I will start by showing how you can use what has become an almost full featured WMI client.

One of the most common perceptions of windows is that it is a PUI (PARC User interface) oriented operation system. In other words the mouse is required to do everything. This is in many places true but fortunately Microsoft has recently changed this and incorporated the keyboard more and more into what was previously a mouse only domain. With Vista and Windows 7 a whole range of new keyboard shortcuts emerged and slapping on some third-party tools on top of that and we get a full-fledged keyboard experience.