Sematext Monitoring is a full-stack IT infrastructure monitoring software that gives you real-time visibility across your infrastructure. Whether on-premise, in the cloud, or a mix of anything in between, Sematext can monitor your whole stack.

Sophisticated Uptime Monitoring for your Apps, DBs, IT systems, and business services. Get pro-active alerts and fix incidents with ease without the noise.

phpSysInfo: a customizable PHP script that displays information about your system nicely

The alerta monitoring system is a tool used to consolidate and de-duplicate alerts from multiple sources for quick ‘at-a-glance’ visualisation. With just one system you can monitor alerts from many other monitoring tools on a single screen.

Health checking for any application and infrastructure written in any language inc. BASH, Python, PHP, Perl - riotkit-org/infracheck

Agentless monitor covers most of the aspects of monitoring like JAVA / J2EE application monitoring, server monitoring, database monitoring, transaction monitoring, network monitoring, log monitoring and system monitoring and last, but not the least is available for free.

CloudMonix provides advanced cloud monitoring and automation for applications and services deployed on the Microsoft Azure and AWS platforms and built with MSPs, CSPs and DevOps in mind.