ElasticSearch Trivia 3 — Questions and Answers
Question 1: What is the maximum recommended number of shards per gigabyte of JVM heap in Elasticsearch?
- 5
- 10
- 20 (Correct answer)
- 50
Correct answer: 20
Elasticsearch recommends keeping fewer than 20 shards per GB of heap memory to maintain cluster stability.
Question 2: Which Elasticsearch feature allows you to automatically move data to cheaper storage tiers as it ages?
- Rollup
- ILM (Index Lifecycle Management) (Correct answer)
- Snapshot
- Reindex API
Correct answer: ILM (Index Lifecycle Management)
Index Lifecycle Management (ILM) automates the transition of indices through hot, warm, cold, and frozen tiers based on age or size.
Question 3: What does the '_source' field store in an Elasticsearch document?
- The index name
- The original JSON document as ingested (Correct answer)
- The shard routing key
- The document score
Correct answer: The original JSON document as ingested
The '_source' field stores the original JSON body of the document exactly as it was indexed.
Question 4: Which Elasticsearch API is used to perform multiple index/delete/update operations in a single request?
- Multi Search API
- Bulk API (Correct answer)
- Pipeline API
- Batch API
Correct answer: Bulk API
The Bulk API allows sending multiple create, index, update, and delete actions in a single HTTP request for better throughput.
Question 5: What is the role of a 'coordinating node' in an Elasticsearch cluster?
- Stores data shards
- Elects the master
- Routes requests and merges results (Correct answer)
- Handles snapshot operations only
Correct answer: Routes requests and merges results
A coordinating node receives client requests, routes them to the appropriate data nodes, and aggregates the results before responding.
Question 6: Which tool in the Elastic Stack is used for data visualization and dashboards?
- Logstash
- Beats
- Kibana (Correct answer)
- Fleet
Correct answer: Kibana
Kibana is the visualization layer of the Elastic Stack, providing dashboards, charts, and management UIs for Elasticsearch data.
Question 7: What Elasticsearch concept allows you to define templates applied automatically to new indices matching a pattern?
- Alias
- Index Template (Correct answer)
- Data Stream
- Pipeline
Correct answer: Index Template
Index templates define settings, mappings, and aliases that are automatically applied when a new index is created matching a specified pattern.
ElasticSearch Trivia 3
What is the maximum recommended number of shards per gigabyte of JVM heap in Elasticsearch?