We’ve reviewed Munin as a simple solution for basic monitoring. Now let’s move on to a stack that has become an indispensable tool in the world of modern cloud infrastructure, microservices, and containers: Prometheus, Node Exporter, and Grafana. This trio provides a powerful, flexible, and scalable approach to collecting, storing, analyzing, and visualizing metrics.

What is Prometheus and Its Ecosystem?

Prometheus is an open-source monitoring system originally developed at Google and later handed over to the Cloud Native Computing Foundation (CNCF). Its key feature is the “pull” model: Prometheus scrapes metrics from targets via HTTP endpoints.

Key components of the Prometheus ecosystem:

• Prometheus Server — the core of the system that collects metrics, stores them in a TSDB (time-series database), processes PromQL queries, and generates alerts.
• Exporters — programs that convert system and application data into metrics Prometheus understands. Examples:
  • Node Exporter — collects metrics from Linux servers (CPU, memory, disk, network).
  • kube-state-metrics — exposes the state of Kubernetes objects.
  • mysqld_exporter, postgres_exporter — for databases.
  • blackbox_exporter — for probing service availability.
• Alertmanager — processes alerts from Prometheus, groups, filters, and sends them to Slack, Email, PagerDuty, and others.
• Pushgateway — a component for short-lived jobs that can’t be scraped. These jobs push metrics themselves.

Grafana: The Power of Visualization

Prometheus has a built-in UI, but for full-fledged visualization, Grafana is used.

Grafana is a powerful tool for data visualization and analysis. It supports many data sources (Prometheus, InfluxDB, Elasticsearch, etc.) and enables creation of interactive dashboards with charts, tables, alerts, and other widgets. The Prometheus + Grafana combo is the industry standard.

Advantages of Prometheus + Node Exporter + Grafana

• Scalability and performance: Suitable for monitoring thousands of targets and millions of metrics.
• PromQL: A flexible query language for aggregating, filtering, and analyzing metrics.
• Flexible alerting system: Alertmanager allows grouping, silencing, and routing alerts.
• Deep integration with Grafana: Supports building complex, interactive dashboards.
• Rich ecosystem: Exporters exist for almost any system or application.
• Kubernetes and container support: Automatic service discovery, scalability, and dynamic configuration.

Disadvantages of the Stack

• Complex configuration: Requires understanding of concepts, config files, and PromQL.
• Limited long-term storage: External solutions are needed to store metrics beyond a few weeks (e.g., VictoriaMetrics, Thanos, or Cortex).
• Pull model: Not always suitable for isolated systems (e.g., behind NAT).
• Resource-intensive: Large data volumes may require significant resources.

Usability and Unique Features

This stack is ideal for:

• Dynamic cloud infrastructures (Kubernetes, Docker).
• Microservice architectures with many independent components.
• DevOps teams that need automation and analytics.

Unique features:

• PromQL — a powerful language for advanced queries.
• Service Discovery — automatic detection of new monitoring targets.
• Prometheus Federation — uniting multiple servers for centralized monitoring.

Conclusion

Prometheus + Node Exporter + Grafana is the de facto standard for modern monitoring. This combination offers flexibility, scalability, and powerful analysis tools. Despite its initial complexity, it pays off in cloud-native, containerized, and microservice-based environments.

In the next article, we’ll take a look at Zabbix — an all-in-one solution that fits well with more traditional monitoring approaches.