Zipkin address not consistent between gateway and proxy

Config
1

Hello,

I deployed an zipkin compliant tracing solution in a specific namespace (monitoring)

I used the operator config:

apiVersion: install.istio.io/v1alpha1
kind: IstioOperator
metadata:
  namespace: istio-system
  name: istio-control-plane
spec:
  profile: minimal
  components:
    ingressGateways:
      - name: istio-gateway
        enabled: true
        namespace: gateway
meshConfig:
    enableTracing: true
    defaultConfig:
      tracing:
        zipkin:
          address: collector.monitoring:9411
  values:
    global:
      tracer:
        zipkin:
          address: collector.monitoring:9411

What is stange is that on the tracing application, I got a warning “parent span missing”. I found out that on the gateway, I got a wrong zipking url:

$ istioctl proxy-config gateway -n gateway istio-gateway-xxxxxxxx-yy

[extract]

{
  "bootstrap": {
    "node": {
      "metadata": {
        "ISTIO_VERSION": "1.6.1",
        "PROXY_CONFIG": {
          "discoveryAddress": "istiod.istio-system.svc:15012",
          "tracing": {
            "zipkin": {
              "address": "zipkin.istio-system:9411"
            }
          }
        },

But when I check on the injected proxy on my pod, I got the correct value:

$ istioctl proxy-config gateway -n demo hello-world-xxxxxxxx-yy

[extract]

{
  "bootstrap": {
    "node": {
      "metadata": {
        "PROXY_CONFIG": {
          "tracing": {
            "zipkin": {
              "address": "collector.monitoring:9411"

Did I miss a config somewhere?
From the code I’m not entirely clear how the /etc/istio/proxy/envoy-rev0.json is generated, so if somebody has some pointers…

Thank you

2

For reference, difference between proxy and gateway come from an environment variable set in the proxy and not in the gateway.

I opened an issue https://github.com/istio/istio/issues/24666 with some hint on a possible solution.