By default, Elastic Cloud Enterprise uses the external ip.es.io service provided by Elastic to resolve virtual Elasticsearch cluster host names in compliance with RFC1918. The service works by resolving host names of the form .ip.es.io to . In the case of Elastic Cloud Enterprise, each cluster is assigned a virtual host name of the form ..ip.es.io:, such as https://6dfc65aae62341e18a8b7692dcc97186.10.8.156.132.ip.es.io:9243. The ip.es.io service simply resolves the virtual host name of the cluster to the proxy address which is specified during installation, 10.8.156.132 in our example, so that client requests are sent to the proxy. The proxy then extracts the cluster ID from the virtual host name of the cluster and uses its internal routing table to route the request to the right allocator.

The ip.es.io service is provided to help you evaluate Elastic Cloud Enterprise without having to set up DNS records for your environment. If you do not use the ip.es.io service for your production environment, you must set up a wildcard DNS record. You typically set up a wildcard DNS record that resolves to the proxy host or to a load balancer if you set up multiple proxies fronted by a load balancer. You can create both a wildcard DNS entry for your endpoints and a wildcard TLS/SSL certificate, so that you can create multiple clusters without the need for further DNS or TSL/SSL modifications. Simply configure your DNS to point to your load balancers and install your certificates on them, so that communication with the cluster is secure.

A wildcard certificate is enabled based on the CNAME record that is generated for each cluster. For more information on modifying the CNAME record, see Configure endpoints. The CNAME also determines the endpoint URLs are displayed in the Cloud UI.