Pandora Open
Open Source Monitoring System for performance and availability.
...Pandora FMS consolidates all the needs of modern monitoring (ITOM, APM, BAM) and provides status and performance metrics from different operating systems, cloud, virtual infrastructure (VMware, Hyper-V, XEN), Docker containers, applications, storage and hardware devices such as firewalls, proxies, databases, web servers or routers.
It's highly scalable (up to 2000 nodes with one single server), 100% web and with multi-tenant capabilities. It has a very flexible ACL system and several different graphical reports and user-defined control screens.