Course: Prometheus | The Complete Hands-On for Monitoring & Alerting udemy.com/course/prometheus-course

Architecture

prometheus pulls metrics discovery: hardcoded or service discovery

UI

localhost:9090 up - targets scraped by prometheus

config file

prometheus.yml Plain Text metric_name{key_name=“value”, key=“value”} metric_value

Exporters

get metrics from third-party systems

TODO: PromQL

client libs

prometheus official community

metric types

counter - up / restarted service

gauge - up an down

<name>


app_requests_inprogress

summary - samples

<name>_count
<name>_sum


rate(app_Response_latency_seconds_sum[5m]) / rate(app_Response_latency_seconds_count[5m])

histogram - samples in buckets

<name>_bucket{le="..."}
<name>_bucket{le="..."}
<name>_bucket{le="..."}
<name>_count
<name>_sum



# le = less then or equal to
# -> every request will be in +Inf bucket

Recording rules

recording rules - pre-cached stores new time series of the calculated values