Last updated: July 9, 2026 · Reading time: 2–4 minutes
Anyone involved in monitoring, log analysis, or searching through large amounts of data will sooner or later come across the ELK Stack. The ELK Stack consists of three different tools: Elasticsearch, Logstash, and Kibana. Find out what’s behind it all, how the three components work together, and why the stack is completely free for self-hosting in our article here.
An Overview of the Three Components
ELK is not a single software program, but rather a combination of three tools that are perfectly coordinated with one another.
- Elasticsearch forms the foundation of the stack; this is where everything comes together. Data, logs, and metrics are stored centrally and made searchable in milliseconds. Elasticsearch is the core without which the rest of the stack cannot function.
- Logstash is the data pipeline. It receives raw data from various sources—including log files, system events, and network data—and processes it before it is sent to Elasticsearch. Unstructured text is converted into structured, analyzable objects.
- Kibana is the Stack’s user interface. It connects directly to Elasticsearch and displays the stored data in the form of charts, dashboards, and interactive analyses. What used to require a number of terminal commands can now be seen at a glance with Kibana.
Elasticsearch – Search and Analytics Engine
Elasticsearch is not a traditional database. It is a search and analysis engine based on Apache Lucene. Unlike MySQL or PostgreSQL, Elasticsearch is not designed for transactional operations such as traditional INSERT, UPDATE, or DELETE, but rather for searching and analyzing massive amounts of data in milliseconds.
The key difference from traditional databases lies in the search functionality. A typical database query asks: “Give me all records where Name = ‘Dirk’”— exactly and in a structured way. Elasticsearch, on the other hand, can search through millions of unstructured text documents in milliseconds, tolerate typos, and sort results by relevance. It’s less like a table and more like a Google search for your own data.
Logstash – Converting Unreadable Text into Readable Objects
Raw log data is often unreadable. A typical syslog line looks like this:
May 6 13:02:17 server sshd[1234]: Failed password for root from 192.168.1.1For a database, this is a long, unstructured string that is virtually impossible to analyze. Logstash plays a crucial role here:
It transforms this unreadable text into readable, structured objects. The hostname, process, time, and IP address are recognized and stored as individual fields so that Elasticsearch can search and analyze them later.
Kibana – Say Goodbye to the Terminal
Without Kibana, you’d have to enter a bunch of commands in the terminal to get any information. That’s exactly what Kibana replaces: A single, easy-to-use web interface displays all relevant data in real time—visually, interactively, and without requiring any prior command-line experience.
With customizable dashboards, Kibana is perfect for anything. Whether it’s CPU monitoring, log analysis, or compliance with SIEM regulations. You build a dashboard once, and you have all the important information at a glance.
Who is the ELK Stack suitable for?
From beginners to experts, the ELK Stack offers the right solution for every user. Beginners benefit from Kibana’s pre-built dashboards and intuitive interface. Advanced users leverage Elasticsearch’s powerful query language and build complex Logstash pipelines. Experts, on the other hand, rely on the ELK Stack for mission-critical applications such as SIEM, anomaly detection, and large-scale log analysis.
Conclusion
The ELK Stack is more than just a logging tool. It is a comprehensive platform for processing, storing, and analyzing all types of data. Anyone who has ever set up their own dashboard and seen live data flowing through it will quickly understand why the ELK Stack has become an indispensable part of modern IT infrastructures. And the best part: If you host the ELK Stack yourself, you won’t pay a single euro. All components are completely free to use in the self-hosted version.
Are you using the ELK Stack but still have questions? Our consultants have set up, optimized, and operated the ELK Stack in many different environments. Feel free to get in touch! We’d be happy to take a look at what makes the most sense for your infrastructure.
