Chapter 5, Running a Prometheus Server

1. Then, scrape_timeout will be set to its default – 10 seconds.
2. Besides restarting, the configuration file can be reloaded by either sending a SIGHUP signal to the Prometheus process or sending an HTTP POST request to the /-/reload endpoint if --web.enable-lifecycle is used at startup.
3. Prometheus will look back up to five minutes by default, unless it finds a stale marker, in which case it will immediately consider the series stale.

4. While relabel_configs is used to rewrite the target list before the scrape is performed, metric_relabel_configs is used to rewrite labels or drop samples after the scrape has occurred.
5. As we're scraping through a Kubernetes service (which is similar in function to a load balancer), the scrapes will hit only a single instance of the Hey application at a time.
6. Due to the ephemeral nature of Kubernetes...