Unimus - Unimus is a Network Automation and Configuration management (NCM) solution designed for fast deployment network-wide and ease of use. Unimus does not require learning any abstraction or templating languages, and does not require any coding skills.
Zabbix - Track, record, alert and visualize performance and availability of IT resources
GenieACS - A fast and lightweight TR-069 Auto Configuration Server (ACS)
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.
Oxidized - configuration backup software (IOS, JunOS) - silly attempt at rancid
Prometheus - An open-source systems monitoring and alerting toolkit.