Instrumental
Instrumental is a real-time, high-scale application and server monitoring tool with intelligent alerts, a powerful query language, and free development accounts.
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NGINX Amplify
Amplify is free monitoring tool for NGINX. Amplify offers extended NGINX metric collection, visualization, monitoring, and a static analyzer for NGINX configuration. It's simple to set up, yet powerful enough to bring the much needed insight into NGINX performance. Amplify is a SaaS developed and operated by Nginx, Inc. Keep NGINX up to date and secure with a native monitoring solution.
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ntopng
'ntopng' provides an easy to understand, intuitive interface with a world of options and features to monitor your network.
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