One more addition: For testing we also now wrote a config for the collector that exports traces to both splunk and Jaeger at the same time, so we could see if it was just the collector not registering span-links in general or something else down the line. When doing this, the span links appeared in Jaeger - but were still not visible in Splunk. So we think it's either the (default) configuration for the splunk-opentelemetry-collector (specifically the splunk export) not handling span-links, or something in the Observability Cloud not accepting our span-links. There is one more hint I got from the collector container logs, following message that appears a few seconds after the traces are sent: 2025-01-27T14:35:00.707Z info transport/http2_server.go:662 [transport] [server-transport 0xc0022ba000] Closing: EOF {"grpc_log": true} 2025-01-27T14:35:00.707810569Z 2025-01-27T14:35:00.707Z info transport/controlbuf.go:577 [transport] [server-transport 0xc0022ba000] loopyWriter exiting with error: transport closed by client {"grpc_log": true} This might indicate that the writer is stuck at sending the span links, since everything else is sent to splunk correctly. However, I am not sure about the inner workings there. I would appreciate any hints for debugging this! ... View more

Hi, thanks for your answer! We manually instrument our code and include span links, and we can see that it works when using Jaeger instead of splunk. When trying your example via curl the span link didn't show up in the waterfall view either, so maybe our collector isn't set up correctly? We are using the docker container ( quay.io/signalfx/splunk-otel-collector:latest ) with the default configuration. However, I could not find any hints in the docs on what to configure for span links to work.   ... View more