new traces for every request, parent-id changes everytime.

[luck0r]

Describe the bug

I have requests to grafana dashboards http://url/**d**/
these have datasources querys ( http requests) and i want for every request to a dashboard to see all querys as spans. Problem is that all requests are in seperate traces. I tried several configuration options.
Here is my configuration:

location / {
    otel_trace on;                 
    otel_span_name "frontend-request";
    proxy_pass http://localhost:3001;
    include /etc/nginx/proxy.conf;

}
  location /d/ {
    otel_trace on;                
    otel_span_name "dashboard-request";
    otel_trace_context extract;
    proxy_set_header traceparent "00-$otel_trace_id-$otel_span_id-01";  
    proxy_set_header tracestate $http_tracestate;
    proxy_pass http://localhost:3001;
    include /etc/nginx/proxy.conf;

}
    location /api/ {
    otel_trace on;
    otel_trace_context propagate;
    otel_span_name "api";
    proxy_set_header traceparent "00-$otel_trace_id-$otel_span_id-01";  
    proxy_set_header tracestate $http_tracestate;
    include /etc/nginx/proxy.conf;
    proxy_pass http://localhost:3001/api/;

  }

To reproduce

Steps to reproduce the behavior:

1. open a dashboard /d/uid
2. See in nginx log files that all parent ids are different.

Expected behavior

one requests creates a parted id and that is used in the "subrequests"

Your environment

packages from nginx.org( i tried stable and mainline):#
nginx 1.27.3-1~jammy

nginx-module-otel 1.27.3+0.1.0-1~jammy

[p-pautov]

I suspect that the parent needs to be set by browser for this to work. Can you describe the issue with curl as a client?