ELK Stack

Overview

The ELK stack combines Elasticsearch, Logstash, and Kibana for log ingestion, search, and visualization.

Components

• Elasticsearch for indexing and search
• Logstash for ingestion and transformation
• Kibana for dashboards and analysis

flowchart LR
    A[Applications] --> B[Logstash]
    B --> C[Elasticsearch]
    C --> D[Kibana]

Practical Example

input {
  beats { port => 5044 }
}
filter {
  json { source => "message" }
}
output {
  elasticsearch { hosts => ["http://elasticsearch:9200"] }
}

Production Example

A retail platform uses ELK dashboards to monitor checkout errors by region during seasonal spikes.

Common Pitfalls

• Large unbounded index growth
• Heavy queries without index lifecycle tuning
• Lack of role-based access for sensitive logs

Key Takeaways

• ELK is powerful for centralized search and analytics.
• Index lifecycle management is necessary for scale.
• Access control is required for compliance.