Hi,
After upgrading our Filebeat to 6.3.1, we get error on our Logstash servers that consume these logs from Kafka and insert to Elasticsearch (5.3)
[2018-08-01T09:19:04,028][WARN ][logstash.outputs.elasticsearch] Could not index event to Elasticsearch. {:status=>400, :action=>["index", {:_id=>nil, :_index=>"tag-mediation-2018.08.01", :_type=>"logs", :_routing=>nil}, 2018-08-01T09:19:03.185Z {"name":"tagmediation-i-0c6dadf01c99ec637.eu-west-1.production"} %{message}], :response=>{"index"=>{"_index"=>"tag-mediation-2018.08.01", "_type"=>"logs", "_id"=>"AWT0yJcsvdiggc-2mDWo", "status"=>400, "error"=>{"type"=>"mapper_parsing_exception", "reason"=>"failed to parse [host]", "caused_by"=>{"type"=>"illegal_state_exception", "reason"=>"Can't get text on a START_OBJECT at 1:656"}}}}}