Zabbix - Track, record, alert and visualize performance and availability of IT resources
Apache Tomcat - An open source software implementation of the Java Servlet and JavaServer Pages technologies
Datadog - See metrics from all of your apps, tools & services in one place with Datadog's cloud monitoring as a service solution. Try it for free.
Microsoft IIS - Internet Information Services is a web server for Microsoft Windows
Prometheus - An open-source systems monitoring and alerting toolkit.
Apache HTTP Server - Apache httpd has been the most popular web server on the Internet since April 1996