I'm getting a random error while running logstash.
It seems like it happens even with a very low number of events.
Our development includes custom filters that run querys and updates on Elasticsearch (Elastic Cloud)
[2018-09-12T21:02:41,210][FATAL][logstash.runner ] An unexpected error occurred! {:error=>#<Faraday::ConnectionFailed>, :backtrace=>["org/jruby/ext/socket/RubyTCPSocket.java:112:in `initialize'", "uri:classloader:/META-INF/jruby.home/lib/ruby/stdlib/resolv-replace.rb:25:in `initialize'", "org/jruby/RubyIO.java:1154:in `open'", "uri:classloader:/META-INF/jruby.home/lib/ruby/stdlib/net/http.rb:885:in `block in connect'", "org/jruby/ext/timeout/Timeout.java:149:in `timeout'", "uri:classloader:/META-INF/jruby.home/lib/ruby/stdlib/net/http.rb:883:in `connect'", "uri:classloader:/META-INF/jruby.home/lib/ruby/stdlib/net/http.rb:868:in `do_start'", "uri:classloader:/META-INF/jruby.home/lib/ruby/stdlib/net/http.rb:857:in `start'", "uri:classloader:/META-INF/jruby.home/lib/ruby/stdlib/net/http.rb:1409:in `request'", "/usr/share/logstash/vendor/bundle/jruby/2.3.0/gems/faraday-0.9.2/lib/faraday/adapter/net_http.rb:82:in `perform_request'", "/usr/share/logstash/vendor/bundle/jruby/2.3.0/gems/faraday-0.9.2/lib/faraday/adapter/net_http.rb:40:in `block in call'", "/usr/share/logstash/vendor/bundle/jruby/2.3.0/gems/faraday-0.9.2/lib/faraday/adapter/net_http.rb:87:in `with_net_http_connection'", "/usr/share/logstash/vendor/bundle/jruby/2.3.0/gems/faraday-0.9.2/lib/faraday/adapter/net_http.rb:32:in `call'", "/usr/share/logstash/vendor/bundle/jruby/2.3.0/gems/faraday-0.9.2/lib/faraday/rack_builder.rb:139:in `build_response'", "/usr/share/logstash/vendor/bundle/jruby/2.3.0/gems/faraday-0.9.2/lib/faraday/connection.rb:377:in `run_request'", "/usr/share/logstash/vendor/bundle/jruby/2.3.0/gems/elasticsearch-transport-5.0.5/lib/elasticsearch/transport/transport/http/faraday.rb:23:in `block in perform_request'", "/usr/share/logstash/vendor/bundle/jruby/2.3.0/gems/elasticsearch-transport-5.0.5/lib/elasticsearch/transport/transport/base.rb:262:in `perform_request'", "/usr/share/logstash/vendor/bundle/jruby/2.3.0/gems/elasticsearch-transport-5.0.5/lib/elasticsearch/transport/transport/http/faraday.rb:20:in `perform_request'", "/usr/share/logstash/vendor/bundle/jruby/2.3.0/gems/elasticsearch-transport-5.0.5/lib/elasticsearch/transport/client.rb:131:in `perform_request'", "/usr/share/logstash/vendor/bundle/jruby/2.3.0/gems/elasticsearch-api-5.0.5/lib/elasticsearch/api/actions/search.rb:183:in `search'", "/usr/share/logstash/vendor/local_gems/08d2badb/logstash-filter-metric-1.0.0/lib/logstash/filters/metric.rb:230:in `is_authenticated'", "/usr/share/logstash/vendor/local_gems/08d2badb/logstash-filter-metric-1.0.0/lib/logstash/filters/metric.rb:127:in `filter'", "/usr/share/logstash/logstash-core/lib/logstash/filters/base.rb:143:in `do_filter'", "/usr/share/logstash/logstash-core/lib/logstash/filters/base.rb:162:in `block in multi_filter'", "org/jruby/RubyArray.java:1734:in `each'", "/usr/share/logstash/logstash-core/lib/logstash/filters/base.rb:159:in `multi_filter'", "/usr/share/logstash/logstash-core/lib/logstash/filter_delegator.rb:44:in `multi_filter'", "(eval):1574:in `block in filter_func'", "/usr/share/logstash/logstash-core/lib/logstash/pipeline.rb:340:in `filter_batch'", "/usr/share/logstash/logstash-core/lib/logstash/pipeline.rb:319:in `worker_loop'", "/usr/share/logstash/logstash-core/lib/logstash/pipeline.rb:285:in `block in start_workers'"]}