This could be an interesting alternative to using OpenTSDB for time series data.

https://blog.timescale.com/blog/create-a-data-pipeline-with-timescaledb-and-kafka/

https://github.com/timescale/timescaledb-kubernetes

https://docs.timescale.com/latest/getting-started/installation

https://docs.confluent.io/3.1.1/connect/connect-jdbc/docs/sink_connector.html