Large Elasticsearch cluster management

The Centralised Elasticsearch Service at CERN runs the infrastructure to provide Elasticsearch clusters for more than 100 different use cases.This contribution presents how the infrastructure is managed, covering the resource distribution, instance creation, cluster monitoring and user support. The contribution will present the components that have been identified as critical in order to share resources and minimise the amount of clusters and machines needed to run the service. In particular, all the automation for the instance configuration, including index template management, backups and visualisation settings, will be explained in detail.