Amazon Elasticsearch Service is a managed service that makes it easy to deploy, operate, and scale Elasticsearch on AWS. You can now add up to 20 data nodes and 5 dedicated master nodes to your Amazon Elasticsearch domains. The previous limit was a total instance count of 10 including both data nodes and dedicated master nodes. This effectively increases the maximum amount of data you can store in an Amazon Elasticsearch domain from 12 TB to 24 TB with i2.2xl instances and from 4 TB to 8 TB for EBS-backed domains. For more information, see Creating and Configuring Amazon ES Domains and Amazon Elasticsearch Service Limits in the Amazon Elasticsearch Service Developer Guide.