Sampling strategies doesn't seem to work

[RieUchdia]

Hi, I have a question regarding probabilistic sampling in jaeger-collector.
I'm configuring Jaeger collector sampling using a json file named strategies.json for a Jaeger distributed system. And I'm using a docker-compose for Jaeger collector and the query.

Here is the strategies.json file I used,

{
  "service_strategies": [
    {
      "service": "<My service A>",
      "type": "probabilistic",
      "param": 0.0
    },
    {
      "service": "<My service B>",
      "type": "probabilistic",
      "param": 0.0
    }
  ],
  "default_strategy": {
    "type": "probabilistic",
    "param": 0.0
  }
}

and here is the docker-compose file I used,

version: "3.1"

services:
  jaeger-collector:
    image: jaegertracing/jaeger-collector
    volumes:
      - "./jaeger/:/etc/jaeger/"
    command:
      [
        "--es.num-shards=1",
        "--es.num-replicas=0",
        "--es.server-urls=http://elasticsearch:9200",
        "--collector.zipkin.host-port=:9411",
        "--sampling.strategies-file=/etc/jaeger/sampling.json",
      ]
    ports:
      - "14269"
      - "14268:14268"
      - "14250:14250"
      - "9411:9411"
    environment:
      - SPAN_STORAGE_TYPE=elasticsearch
      - LOG_LEVEL=debug
    restart: on-failure
    links:
      - elasticsearch
  jaeger-query:
    image: jaegertracing/jaeger-query
    command:
      [
        "--es.num-shards=1",
        "--es.num-replicas=0",
        "--es.server-urls=http://elasticsearch:9200",
      ]
    ports:
      - "16686:16686"
      - "16687"
    environment:
      - SPAN_STORAGE_TYPE=elasticsearch
      - LOG_LEVEL=debug
    restart: on-failure
    links:
      - elasticsearch
networks:
  default:
    external:
      name: environment_network

I would expect that, the samplingRate: 0 applies and those traces will not be stored.

The jaeger-client within application is configured to use remote-sampling.
Any suggestions on what may be the issue, or how can I troubleshoot this further?

[joe-elliott]

By default the Jaeger client will attempt to send traces to localhost:6831. I'm unsure if your docker-compose correctly sets up communication on localhost between jaeger-query and jaeger-collector. Since I don't see any other applications I assume that you're tracing Jaeger query here?

Configuration env vars here: https://github.com/jaegertracing/jaeger-client-go

I would expect that, the samplingRate: 0 applies and those traces will not be stored.

Can you be more explicit about what you're seeing and what you expect?

[joe-elliott]

No, that warning simply means that the parent of the pictured span could not be found. So, for whatever reason, a span was dropped somewhere.

[yurishkuro]

sampling data will only be present on the root span of the trace

[RieUchdia]

It is solved！
Thank you for your kind support！

[joe-elliott]

Do you mind posting the solution? It might help others with similar issues.

[RieUchdia]

Sure.

Sampling strategies didn't seem to work because the root span generated in my client machine was dropped.
The root span was lost due to an incorrect env var (JAEGER_AGENT_HOST) of the client machine.

Sampling strategies work after I fix JAEGER_AGENT_HOST.