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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.
PagerDuty provides their security training materials[1] for free online, and you can view and build them from source, too (they accept corrections as GitHub pull requests).
[1] - https://github.com/PagerDuty/security-training/
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