Attempted to resurrect connection to dead ES instance

[alexus]

I keep getting flooded with following messages inside of my /var/log/logstash/logstash-plain.log:

[2017-05-08T21:24:21,589][INFO ][logstash.outputs.elasticsearch] Running health check to see if an Elasticsearch connection is working {:healthcheck_url=>http://0:9200/, :path=>"/"}
[2017-05-08T21:24:21,594][WARN ][logstash.outputs.elasticsearch] Attempted to resurrect connection to dead ES instance, but got an error. {:url=>#<URI::HTTP:0xa7bcc0a URL:http://0:9200/>, :error_type=>LogStash::Outputs::Elasticsearch::HttpClient::Pool::HostUnreachableError, :error=>"Elasticsearch Unreachable: [http://0:9200/][Manticore::SocketException] Connection refused (Connection refused)"}

yet

root@linode1:/# curl 0:9200
{
  "name" : "linode1",
  "cluster_name" : "digaweb",
  "cluster_uuid" : "ag15KcHMRPG9ANWmleitfQ",
  "version" : {
    "number" : "5.4.0",
    "build_hash" : "780f8c4",
    "build_date" : "2017-04-28T17:43:27.229Z",
    "build_snapshot" : false,
    "lucene_version" : "6.5.0"
  },
  "tagline" : "You Know, for Search"
}
root@linode1:/# 

Please advise.