collectd
A daemon that collects system performance statistics periodically, and provides tons of plugins to store and analyze these values
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Consul
Consul makes it simple for services to register themselves and to discover other services via a DNS or HTTP interface. Register external services such as SaaS providers as well
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PowerShell Desired State Configuration
DSC is a new management platform in Windows PowerShell that enables deploying and managing configuration data for software services and managing the environment in which these services run.
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Zabbix
An open source, enterprise-class monitoring framework
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