Elastic Search Concepts

• Elastic Search is Distributed Store for documents in json format which is horizontally scalable & it is effecient in searching text
• Shards and Replicas
  
• In Elastic Search, When we insert documents an Inverted Index is built Refer Here
  
• From the above concepts:
  • How Elastic search works even when server(s) in cluster is down?
    • Shards and Replicas
  • Why Elastic Serarch is good at searching text?
    • Inverted Index

Exercise:

• Try Building inverted index for the following data

Until one has loved an animal, a part of ones soul remains unawakened. –Anatole France
Animals are such agreeable friends—they ask no questions; they pass no criticisms. –George Eliot
An animals eyes have the power to speak a great language.–Martin Buber
The better I get to know men, the more I find myself loving dogs. –Charles de Gaulle
Dogs are our link to paradise. They don't know evil or jealousy or discontent. –Milan Kundera

• What would be the ideal number of shards and replicas when i have 5 servers and assume the cluster to work even if two nodes are down