Free ElasticSearch Questions and Answers — Questions and Answers

Question 1: Elasticsearch is a what kind of database?

Graph
Object Oriented
Relational
NoSQL (Correct answer)

Correct answer: NoSQL

Elasticsearch is a distributed, RESTful search and analytics engine built on Apache Lucene. It is categorized as a NoSQL database, specifically a document-oriented database, because it stores data in schema-less JSON documents rather than structured tables with predefined schemas. This flexible data model allows for easy storage and retrieval of diverse data types, making it highly suitable for full-text search, log analysis, and real-time analytics.

Question 2: What is the bare minimum of master nodes that a cluster must have?

one
two
three (Correct answer)
four

Correct answer: three

For a production Elasticsearch cluster, it is recommended to have a minimum of three dedicated master-eligible nodes. This configuration helps prevent split-brain scenarios, where different parts of the cluster disagree on the cluster state, by ensuring a quorum (majority) can always be formed. With three nodes, even if one fails, the remaining two can still form a quorum and maintain cluster stability and availability.

Question 3: An Elasticsearch cluster may have a variety of nodes, including the following:

Internal, External, Bridge
Controller, Worker, Storage
Master, Slave, Agent
Master, Data, Coordinating (Correct answer)

Correct answer: Master, Data, Coordinating

Elasticsearch clusters are composed of different types of nodes, each with specific responsibilities. Master nodes manage the cluster state, data nodes store and index data, and coordinating nodes handle search requests and distribute them across data nodes. Other specialized node types like ingest nodes and machine learning nodes also exist, but Master, Data, and Coordinating are the fundamental categories.

Question 4: A tool called Kibana is used for:

Shipping Data
Container orchestration
Data visualization (Correct answer)
Service discovery

Correct answer: Data visualization

Kibana is an open-source data visualization and exploration tool designed to work with Elasticsearch. It allows users to create interactive dashboards, charts, and graphs from data stored in Elasticsearch indices. Kibana is a crucial component of the Elastic Stack (ELK Stack), enabling users to analyze, visualize, and share insights from their data in real-time.

Question 5: Which Elastic Beat is employed for data transmission from files?

Packetbeat
Filebeat (Correct answer)
Heartbeat
Metricbeat

Correct answer: Filebeat

Filebeat is a lightweight shipper from the Elastic Beats family, specifically designed to forward log files and other file-based data to Elasticsearch or Logstash. It monitors specified directories for changes, collects new log entries, and sends them efficiently. This makes Filebeat ideal for collecting data from various applications and servers without consuming significant system resources.

Question 6: Data can only be sent from Filebeat to Elasticsearch and Logstash.

Yes
No (Correct answer)

Correct answer: No

While Filebeat commonly sends data to Elasticsearch and Logstash, it is not limited to these two destinations. Filebeat can also be configured to send data to other outputs, such as Apache Kafka, Redis, or even directly to standard output for debugging. This flexibility allows users to integrate Filebeat into various data processing pipelines beyond the core Elastic Stack.

Question 7: The parts of a Logstash Pipeline are as follows.

Get, Update, Post
Collect, Transform, Upload
Receive, Mutate, Send
Input, Filter, Output (Correct answer)

Correct answer: Input, Filter, Output

A Logstash pipeline consists of three main stages: Input, Filter, and Output. The Input stage defines where Logstash collects data from (e.g., files, Kafka, beats). The Filter stage processes and transforms the data (e.g., parsing, enriching, mutating). Finally, the Output stage specifies where the processed data should be sent (e.g., Elasticsearch, S3, Kafka).

Free ElasticSearch Questions and Answers

Elasticsearch is a what kind of database?