Command
curl -X GET 'http://localhost:9200/_cluster/stats?pretty'Explanation
Provides a detailed snapshot of the Elasticsearch cluster including node, index, and shard-level metrics such as document counts, memory usage, and storage size.
Common Use Cases
- •Gathering performance metrics for dashboards
- •Capacity planning and scaling decisions
- •Troubleshooting data distribution issues
Best Practices
- ✓Regularly collect stats for performance baselines
- ✓Use tools like Metricbeat or OpenTelemetry to ingest stats automatically
Common Mistakes to Avoid
- ⚠Not using `?pretty` which makes output hard to read
- ⚠Confusing `_cluster/stats` with `_cat/indices` which provides index-level info only
Troubleshooting
Problem: High heap memory usage
Solution: Review field data cache and consider adjusting JVM heap size.
Problem: Unbalanced shard allocation
Solution: Review `cluster.routing.allocation` settings or rebalance nodes.
Examples
Cluster stats without pretty print
curl -X GET 'http://localhost:9200/_cluster/stats'