Example of the issue (b3-headers not propagated to external auth service) envoyproxy/envoy#6520
To run you must have Docker installed. This repo contains the resources to setup Envoy proxy in front of a service (my-service) and an external authorization service (auth-service, see https://github.com/enbohm/authz-service)
To start run docker-compose up --build in directory src/main/docker/
To send a request execute
curl -X GET "http://127.0.0.1:8080/"
Open a browser and type http://127.0.0.1:16686 (Jeager UI)
Notice that the front-proxy and my-service is part of the same trace. The external auth-service is not (but shows up as a standalone service see JaegerUI
Also note that the curl-command prints header present in the 'my-service', INCL. b3-trace headers. The log output from the auth-service does NOT print these headers since they are not propagated to the exteral auth-service see auth-logs. This trace shows up in Jaeger as 'standalone' since they can't be part of a trace due to missing b3-headers JaegerUI-auth-standalone