Nagios is one of the most popular Open Source application being used for the purpose of IT Infrastructure and Network Monitoring. Basically, this tool is available in two editions, namely, Nagios Core edition which is Open Source and absolutely free to download and Nagios XI edition that has to be purchased by the user. Of course, Nagios XI will have additional features as compared to Nagios Core, but when configured with additional open source plugins and softwares, Nagios Core can provide you with similar or exact results as those in Nagios XI. But, using open source tools is always preferred by most of the users.
He we begin!
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