Warning in logs => A gauge metric of an unknown type (org.jruby.specialized.RubyArrayOneObject) has been created for key: send_to #13106
Description
Logstash 7.13.1 from RPM with systemd, Red Hat 8
After starting to use inter pipeline communication with the pipeline output, I started seeing the following warnings in our Logstash logs:
[2021-07-28T17:34:33,187][WARN ][org.logstash.instrument.metrics.gauge.LazyDelegatingGauge][net-sflow-01] A gauge metric of an unknown type (org.jruby.specialized.RubyArrayOneObject) has been created for key: send_to. This may result in invalid serialization. It is recommended to log an issue to the responsible developer/development team.
[2021-07-28T17:34:33,189][WARN ][org.logstash.instrument.metrics.gauge.LazyDelegatingGauge][net-sflow-01] A gauge metric of an unknown type (org.jruby.specialized.RubyArrayOneObject) has been created for key: send_to. This may result in invalid serialization. It is recommended to log an issue to the responsible developer/development team.
Speicific configuration triggering the above warning:
output {
if [sflow_type] == "flow_sample" or [sflow_type] == "expanded_flow_sample" {
pipeline {
send_to => ["net-sflow-sample-01"]
}
}
else if [sflow_type] == "counter_sample" {
pipeline {
send_to => ["net-sflow-counter-01"]
}
}
}