你好，
我的elk版本是5.6，logstash日志里频繁出现报错""undefined method `sanitized' "
每次，刚开始启动的时候是一切正常的，然后慢慢就会出现下面这种报错，积攒到某一天，就会发现不往elastic里写索引数据了。这时候产看日志每天会有7 、 8 M都是刷这个错误。
然后我重启logstash就看似又恢复正常了！
有没有什么好的解决办法？日志内容如下：
[2018-12-07T06:02:38,323][ERROR][logstash.outputs.elasticsearch] Encountered an unexpected error submitting a bulk request! Will retry. {:error_message=>"undefined method sanitized' for \"http://10.0.67.7:9222/_bulk\":String", :class=>"NoMethodError", :backtrace=>["/rmp/logstash-5.6.1/vendor/bundle/jruby/1.9/gems/logstash-output-elasticsearch-7.4.0-java/lib/logstash/outputs/elasticsearch/common.rb:249:insafe_bulk'", "/rmp/logstash-5.6.1/vendor/bundle/jruby/1.9/gems/logstash-output-elasticsearch-7.4.0-java/lib/logstash/outputs/elasticsearch/common.rb:222:in safe_bulk'", "/rmp/logstash-5.6.1/vendor/bundle/jruby/1.9/gems/logstash-output-elasticsearch-7.4.0-java/lib/logstash/outputs/elasticsearch/common.rb:119:insubmit'", "/rmp/logstash-5.6.1/vendor/bundle/jruby/1.9/gems/logstash-output-elasticsearch-7.4.0-java/lib/logstash/outputs/elasticsearch/common.rb:87:in retrying_submit'", "/rmp/logstash-5.6.1/vendor/bundle/jruby/1.9/gems/logstash-output-elasticsearch-7.4.0-java/lib/logstash/outputs/elasticsearch/common.rb:38:inmulti_receive'", "/rmp/logstash-5.6.1/logstash-core/lib/logstash/output_delegator_strategies/shared.rb:13:in multi_receive'", "/rmp/logstash-5.6.1/logstash-core/lib/logstash/output_delegator.rb:49:inmulti_receive'", "/rmp/logstash-5.6.1/logstash-core/lib/logstash/pipeline.rb:436:in output_batch'", "org/jruby/RubyHash.java:1342:ineach'", "/rmp/logstash-5.6.1/logstash-core/lib/logstash/pipeline.rb:435:in output_batch'", "/rmp/logstash-5.6.1/logstash-core/lib/logstash/pipeline.rb:381:inworker_loop'", "/rmp/logstash-5.6.1/logstash-core/lib/logstash/pipeline.rb:342:in `start_workers'"]}