Tracing via DORA_JAEGER_TRACING does not work

[dreamroboat]

Describe the bug
When following the official Dora tracing guide
https://dora-rs.ai/docs/guides/Debugging/tracing

and configuring Jaeger as instructed, Dora does not emit any tracing data to Jaeger.
As a result, no Dora-related services or spans appear in the Jaeger UI, and it is not possible to observe per-node message processing or input/output latency.

This makes it currently impossible to use tracing to monitor dataflow-level or node-level latency, despite tracing being presented as the recommended observability mechanism.

To Reproduce
Steps to reproduce the behavior:
1、Start Jaeger (all-in-one) locally:
docker run -d \ -p6831:6831/udp -p6832:6832/udp -p16686:16686 \ jaegertracing/all-in-one:latest

2、Export the tracing environment variable as described in the documentation:
export DORA_JAEGER_TRACING=127.0.0.1:6831

3、Start the Dora daemon:
dora up

4、Start a dataflow:
dora start dataflow.yaml

5. Let the dataflow run for some time (nodes are active and exchanging messages).
   Open Jaeger UI at:http://localhost:16686

Expected behavior
When DORA_JAEGER_TRACING is set and a dataflow is running:

• Dora should emit tracing spans to Jaeger.
• Dora-related services should appear in the Jaeger UI.
• It should be possible to observe:
  • Per-node message processing time
  • Input → output latency within a node
  • End-to-end latency across multiple nodes in a dataflow
  • This is the behavior implied by the official tracing documentation.

Environments (please complete the following information):

• System info: [Linux robot-System-Product-Name 6.8.0-90-generic Add metadata serialisation for python operator #91~22.04.1-Ubuntu SMP PREEMPT_DYNAMIC Thu Nov 20 15:20:45 UTC 2 x86_64 x86_64 x86_64 GNU/Linux]
• Dora version: [dora-cli 0.3.12]

Additional context
Add any other context about the problem here.

[haixuanTao]

Hi sorry to hear, I think jaeger stopped working lately. I have opened #1259 as a fix and with it you should be able to see traces with the following example:

export DORA_OTLP_ENDPOINT=http://0.0.0.0:4317
cd examples/python-log
dora run dataflow.yaml  --uv                                                                                                   

Make sure to have signoz running with https://signoz.io/docs/install/docker/

More or less:

git clone -b main https://github.com/SigNoz/signoz.git && cd signoz/deploy/
./install.sh

Jaeger is slowly being depreciated in favor of better more integrated system like signoz.

[haixuanTao]

If you're able to make it work I'll update the documentation.

[DEFAULTE-R]

I can take this on.

I’ll try validating the SigNoz + OTLP setup using GitHub Codespaces (since Jaeger seems deprecated) and report back with exact steps and findings. If it works, I can open a docs PR to update the tracing guide accordingly.