可以通过快照snapshot的方式将数据备份到S3，然后从S3将原数据恢复restore到新集群，相关资料可以参见相关文档。
https://www.elastic.co/guide/en/cloud/current/ec-aws-custom-repository.html
https://www.elastic.co/guide/en/elasticsearch/reference/7.16/snapshots-restore-snapshot.html
https://www.elastic.co/guide/en/elasticsearch/reference/7.16/snapshots-restore-snapshot.html#restore-different-cluster