How can I forward my sl4j logs which are generated in my spring microservices to otel-collector ?

[yatamraghu7]

Hi Fellow Developer,
In my spring microservices I am using sleuth with otel combination to forward my traces to otel-collector and I am successful in forwarding my traces. But not able to achieve forwarding my logs to otel-collector.
I can see that opentelemetry is supporting multiple logging mechanisms which are being used in java but I have not found anything related to sl4j. Can someone guide me how can i forward my sl4j logs to otel-collector.
Thanks in advance.
Reagrd,
Raghu

[laurit]

sl4j is a logging facade, actual logging is performed by an logging framework such as logback, log4j etc. Check what is the actual logging framework that you use.

[yatamraghu7]

Hi @laurit

I am sending curl as below with X-B3 header to pass my custom traceId and spanId and when I see the traces in my qryn backend the traceid is modified

H 'Content-Type: application/json'
-H 'X-B3-TraceId: 1111111111111111'
-H 'X-B3-SpanId: 2222222222222222'
-H 'X-B3-Sampled: 1'
-d '{
"id":7,
"name":"raghu"
}'

Can you please help me how can i get the traceId which I am sending with my request header into my backend trace viewer.

The logs which I was telling before for a specific service If I filter my query with application name I can only see the metrics.
Attached the screenshots.

Thanks
Raghu Ram

[laurit]

I am sending curl as below with X-B3 header to pass my custom traceId and spanId and when I see the traces in my qryn backend the traceid is modified

By default otel uses w3c trace context headers to propagate context. I'd guess that the b3 hears that you use are just getting ignored. See https://opentelemetry.io/docs/languages/java/configuration/#propagators

[yatamraghu7]

Hi @laurit

Thanks for the help and now I am successfully able to export the logs and traces from my application to otel-collector.
One last question would be do you have any idea how we can export the TraceId and spanId which I can see in my application at INFO and DEBUG level to otel-Collector.
I can only see the logs but not the traceId and spanId. It would be great if you have any document reference.

Thanks
Raghu Ram

[laurit]

Trace and span id are part of the otlp payload. Only when the log message is emitted within a trace will it have a trace/span id. You can confirm this by turning on verbose output in otel collector https://opentelemetry.io/docs/collector/troubleshooting/ If you don't see the trace/span id in your observability backend but see it in the collector then please seek assistance from appropriate channels for your observability backend.