Elasticsearch cross cluster replication, authorization and authentication

Elastic Stack Elasticsearch
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1

To setup cross cluster replication in elasticsearch, what is the authorization and authentication mechanism in between Local and Remote cluster ..? How does local cluster recognize remote cluster.?
@elasticsearch

2

That's explained in https://www.elastic.co/guide/en/elasticsearch/reference/current/ccr-getting-started.html#ccr-getting-started-before-you-begin