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InfluxDB
Power Real-Time Data Analytics at Scale. Get real-time insights from all types of time series data with InfluxDB. Ingest, query, and analyze billions of data points in real-time with unbounded cardinality.
Although as far as hardware, you can get a Raspberry Pi kit for about $80 and install something like https://pivpn.io/. I think if anything it's easier to set up than reverse proxy and the cost is not much more than any other server hardware upgrade.
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