Outline

Observability captures what "montoring" doesn't (and shouldn't)

based on evidences (not conjectures)

Monitoring and Observability by Cindy Sridharan

Highly granular insights into the behavior of systems along with rich context, perfect for debugging purposes.

Provide visibility into the health of a system and the impact of any failure.

Monitoring

Observability

Prometheus Overview

The people We want to use Prometheus!

Multi dimensional data model (metric name + tags)

Large community of users

Flexible query language

Areas of struggles

Storage limited to local disk

Hard to achieve HA

Strong focus on reliability (each service is independent)

Excellent integration with mainstream

technologies

Prometheus FAQ: Why do you pull rather push?

Collects metrics via pulling over HTTP

Each service have to expose metrics via HTTP 

We use Kamon to collect and expose metrics for our Java apps

Each other public project (Kafka, Zookeeper, Cassandra, so on) have to have a way to expose their metrics to Prometheus

Almost all projects based on Java use JXM-Exporter, a Prometheus's Java agent

Thanos | Cortex

Global view

Long term storage

Two widely adopted options:

Easy HA

Cortex Architecture

Cortex uses Consul to distribute metrics handling among nodes and deduplicate the metrics coming from multiple Prometheus.

Require a Storage service for both index and data.

We just chosen Cassandra for lacks of other options. It can be replaced by some other services such as S3, Bigtable, etc.

Prometheus is configured to send every metric to Cortex.

Grafana

Multiple visualization options (histograms, heatmap, tables, ...)

Great integration with Prometheus (also others like InfluxDB, Elastic, etc.)

Alerting

HA

SSO integration (we connected it to ATP3)

Free And Open Source

Visualization for logging and traces (also correlation between logs and metrics)

Require a Storage to provide HA.

Each Grafana node is stateless.

Add some lib to instrument -> collect -> expose the metrics to Prometheus.

Some popular lib for JVM-based apps: Micrometer, Kamon, and so on ...

Register the new service on Consul so Prometheus can auto discover it.

It could be automatic via a Consul client running as sidecar, or manually via sending a request to Consul server.

One more option is using Prometheus-Configurer, which accept the cluster.info file to register a service on Consul.

Checks the metrics are being scraped by Prometheus

Query                                                             on the Prometheus Backoffice.

Configure a dashboard on Grafana

Importing a dashboard (you can find one at

https://grafana.com/grafana/dashboards)

Or creating a new one on your own.

Verification. Verify the endpoint is properly exposed (something like http://localhost:9090/metrics or the path that was configured)

Very cheap compared to ELK

Flexible query language with aggregations (like Prometheus)

Developed by Grafana, so a great integration with our ecosystem

HA and long-term storage

Free And Open Source

Grafana Loki

Logs and metrics in the same place: Grafana UI

Promtail collect log lines, attach to them metadata, and finally ship them to Loki

Log lines are processed by Loki, only metadata is indexed

Grafana ask to Loki for log lines

Applications need to be “instrumented” to report trace data to Zipkin

If you have a trace ID in a log file, you can jump directly to it

Distributed tracing system

Zipkin

It has its own UI

Integration with Grafana allow us to work with Loki logs and correlate them with Zipkin

Distributed Tracing tech talk by Diego Parra and Cristian Spinetta

A few of the critical questions that Tracing can answer quickly and easly:

Which did a request pass through?

Where are the bottlenecks?

How much time is lost due to network lag during communication between services?

What occurred in each service for a given request?

A Zipkin reporter running in each server, in our case Kamon-Zipkin module, ships traces to the Zipkin collector

Zipkin collector process incoming traces, index them and saves to an storage

Now data is available to query thorough Zipkin UI or Grafana