serverless.yml

    ElasticSearchDomain:
      Type: AWS::Elasticsearch::Domain
      Properties:
        DomainName: ${self:custom.es_domain}
        ElasticsearchVersion: "6.2"
        ElasticsearchClusterConfig:
          ZoneAwarenessEnabled: false
          InstanceCount: ${self:custom.es_instanceCount}
          InstanceType: ${self:custom.es_instanceType}
        EBSOptions:
          EBSEnabled: true
          VolumeType: "gp2"
          VolumeSize: ${self:custom.es_ebsVolumeGB}