About logstash-out-mongodb exception

Elastic Stack Logstash
1

hello ,can you help me?
logstash-out-mongodb

input {
stdin{}
}

output{

mongodb {
collection => "std"
database => "fragment"
generateId => true
uri => "mongodb://192.168.199.7:27017"
}
}
~

Failed to send event to MongoDB {:event=>#<LogStash::Event:0x2ef73b32 @metadata={}, @accessors=#<LogStash::Util::Accessors:0x694f67b4 @store={"message"=>"hello", "@version"=>"1", "@timestamp"=>"2016-09-02T05:33:49.575Z", "host"=>"mini03"}, @lut={"host"=>[{"message"=>"hello", "@version"=>"1", "@timestamp"=>"2016-09-02T05:33:49.575Z", "host"=>"mini03"}, "host"], "@timestamp"=>[{"message"=>"hello", "@version"=>"1", "@timestamp"=>"2016-09-02T05:33:49.575Z", "host"=>"mini03"}, "@timestamp"]}>, @data={"message"=>"hello", "@version"=>"1", "@timestamp"=>"2016-09-02T05:33:49.575Z", "host"=>"mini03"}, @metadata_accessors=#<LogStash::Util::Accessors:0x1f036be0 @store={}, @lut={}>, @cancelled=false>, :exception=>#, :backtrace=>["/export/servers/logstash-2.4.0/vendor/bundle/jruby/1.9/gems/logstash-output-mongodb-2.0.5/lib/logstash/outputs/mongodb.rb:54:in receive'", "/export/servers/logstash-2.4.0/vendor/bundle/jruby/1.9/gems/logstash-core-2.4.0-java/lib/logstash/outputs/base.rb:109:inmulti_receive'", "org/jruby/RubyArray.java:1613:in each'", "/export/servers/logstash-2.4.0/vendor/bundle/jruby/1.9/gems/logstash-core-2.4.0-java/lib/logstash/outputs/base.rb:109:inmulti_receive'", "/export/servers/logstash-2.4.0/vendor/bundle/jruby/1.9/gems/logstash-core-2.4.0-java/lib/logstash/output_delegator.rb:130:in worker_multi_receive'", "/export/servers/logstash-2.4.0/vendor/bundle/jruby/1.9/gems/logstash-core-2.4.0-java/lib/logstash/output_delegator.rb:114:inmulti_receive'", "/export/servers/logstash-2.4.0/vendor/bundle/jruby/1.9/gems/logstash-core-2.4.0-java/lib/logstash/pipeline.rb:301:in output_batch'", "org/jruby/RubyHash.java:1342:ineach'", "/export/servers/logstash-2.4.0/vendor/bundle/jruby/1.9/gems/logstash-core-2.4.0-java/lib/logstash/pipeline.rb:301:in output_batch'", "/export/servers/logstash-2.4.0/vendor/bundle/jruby/1.9/gems/logstash-core-2.4.0-java/lib/logstash/pipeline.rb:232:inworker_loop'", "/export/servers/logstash-2.4.0/vendor/bundle/jruby/1.9/gems/logstash-core-2.4.0-java/lib/logstash/pipeline.rb:201:in `start_workers'"], :level=>:warn}

THK!

2

Set generateId to report this exception, how to deal with the request.