Prometheus

A book-shaped table of contents for Prometheus: monitoring foundations through architecture, data model, instrumentation, service discovery, PromQL, alerting, production operation, PCA certification, and MAANG interview prep — cross-linking existing notes instead of duplicating them.

2 — Labels and Cardinality

Label mechanics and series identity in Prometheus — how labels turn one metric name into many time series, the storage/performance cardinality math, and target relabeling vs. metric relabeling with real relabel_configs YAML.

1 — Metrics Deep Dive

The four Prometheus metric types — Counter, Gauge, Histogram, Summary — walked through hands-on across a Linux batch app + Node Exporter and a Windows web app + Windows Exporter, plus the histogram_quantile bucket-math caveat and the Histogram-vs-Summary tradeoff.

3 — Prometheus in the Observability Ecosystem

Where Prometheus sits in the CNCF landscape — its pull-based cloud-native origins, its companion projects, and where this book does (and doesn't yet) connect it to the wider stack.

2 — Exporters

What a Prometheus exporter is, installing Node Exporter as a systemd service, and monitoring the container runtime itself via Docker Engine metrics and cAdvisor.