Nagios is a company with several IT management oriented products: Nagios XI, Nagios Fusion, Nagios Incident Manager and Nagios Network Analyzer. I've played with their base monitoring product - Nagios XI.

According to documentation in Nagios XI there are a lot of wizards for servers and services to auto-discover and integrate with. It looks like very solid platform to help IT departments to monitor their servers and IT infrastructure. 

Nagios XI is a web application and its UI is clear and responsive. 
To install Nagios XI you have 2 options. If your OS is RHEL or CentOS you can do manual installation from source (40MB). Otherwise you need to download and install virtual machine player first (from VMware, vSphere or Microsoft), then you need to download the virtual machine with Nagios itself (up to 700MB). 

Because of such a authentic approach to distribute Nagios XI my attempt to try Nagios XI has failed from the start. I had no problem running VMWare with Nagios locally but I had no possibility to install it to customer's servers with Solaris OS. I've tried to install Nagios XI Solaris agent with no luck with error message like "installation error was detected". At least Nagios XI pricing is very straightforward.

At this point I'd like to thank Nagios company for saving my time and letting me quickly jump to the next monitoring product overview. I do not recommend developers and DevOps to invest their time in configuring Nagios XI.

Best regards,

Vladimir Krasilschik from Kupchino Labs,
Saint-Petersburg, Russia

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