Elastic Cloud already listens to port 443, so there is nothing to change. Try connecting to your cluster on port 443 from a computer with internet access.

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NEW: Monitor These Apps!
elasticsearch, apache solr, apache hbase, hadoop, redis, casssandra, amazon cloudwatch, mysql, memcached, apache kafka, apache zookeeper, apache storm, ubuntu, centOS, red hat, debian, puppet labs, java, senseiDB