How to use Cluster Health API In Databases

The Cluster Health API in Elasticsearch provides a comprehensive overview of the cluster’s health, offering crucial insights into its current state. It is a vital tool for administrators to ensure the cluster operates smoothly.

To access the Cluster Health API, you can use the below-following endpoint:

GET /_cluster/health

This API call returns a JSON object containing several important fields that describe the status of the cluster. Here is an example response.

{
  "cluster_name": "my_cluster",
  "status": "yellow",
  "timed_out": false,
  "number_of_nodes": 3,
  "number_of_data_nodes": 2,
  "active_primary_shards": 5,
  "active_shards": 10,
  "relocating_shards": 0,
  "initializing_shards": 0,
  "unassigned_shards": 2,
  "delayed_unassigned_shards": 0,
  "number_of_pending_tasks": 0,
  "number_of_in_flight_fetch": 0,
  "task_max_waiting_in_queue_millis": 0,
  "active_shards_percent_as_number": 83.3
}

Elasticsearch is a powerful distributed search and analytics engine used by many organizations to handle large volumes of data. Ensuring the health of an Elasticsearch cluster is crucial for maintaining performance, reliability, and data integrity.

Monitoring the cluster’s health involves using specific APIs and understanding key metrics to identify and resolve issues promptly. This article provides an in-depth look at using the Cluster Health API, interpreting health metrics, and identifying common cluster health issues.