CrateDB + Telegraf
CrateDB is a hyper-fast opensource distributed database technology that combines the best out of the SQL and NoSQL worlds. It supports the PostgreSQL wire protocol for easy integration with many data engineering tools.
With Telegraf, it's possible to source metrics directly from the system it’s running on, pull metrics from third-party APIs, and collect sensor data from Internet of Things (IoT) devices. These tasks are made easier by over 200 available plugins, and the ease of plugin development means you can create your own plugin to suit your monitoring needs.