Starting in Logstash 2.0 the elasticsearch output always uses HTTP (which prior to 2.0 was optional via protocol => "http"). When using HTTP the cluster name is irrelevant and you instead need to point to one or more cluster nodes with the hosts option.
Apache, Apache Lucene, Apache Hadoop, Hadoop, HDFS and the yellow elephant
logo are trademarks of the
Apache Software Foundation
in the United States and/or other countries.