TrafficSplit + Ingress

[lucasgrvarela]

How do I make the TrafficSplit/ServiceProfile work with ingress?

We have setup 3 services and created the TrafficSplit config, we tested it and worked well internally but not outside.

apiVersion: split.smi-spec.io/v1alpha2
kind: TrafficSplit
metadata:
  name: canary-split
  namespace: sre-sandbox
spec:
  service: nginx-prod
  backends:
  - service: nginx-prod
    weight: 50
  - service: nginx-baseline
    weight: 25
  - service: nginx-canary
    weight: 25

The ServiceProfile was created automatically by the TrafficSplit

$ k get sp -n sre-sandbox
NAME                                       AGE
nginx-prod.sre-sandbox.svc.cluster.local   45m

If I call my root service inside a pod in the cluster, it's working and we can see the traffic being splitted for the three services we configured. Example:

root@pod-test-canary:/# for i in {1..5}; do curl nginx-prod; done
nginx-prod
nginx-baseline
nginx-canary
nginx-baseline
nginx-baseline
...

ExternalService

$ k -n sre-sandbox get svc
NAME                      TYPE           CLUSTER-IP    EXTERNAL-IP                                PORT(S)   AGE
nginx-external-resolver   ExternalName   <none>        nginx-prod.sre-sandbox.svc.cluster.local   80/TCP    6m42s

Ingress manifest

apiVersion: v1
items:
- apiVersion: networking.k8s.io/v1
  kind: Ingress
  metadata:
    annotations:
      kubernetes.io/ingress.class: nginx
      nginx.ingress.kubernetes.io/service-upstream: "true"
    name: nginx-ingress
    namespace: sre-sandbox
  spec:
    rules:
    - host: canary.abc.com
      http:
        paths:
        - backend:
            service:
              name: nginx-external-resolver
              port:
                number: 80
          path: /
          pathType: ImplementationSpecific

My /etc/hosts

35.xxx.xxx.xxx canary.abc.com

Example calling from outside passing by Ingress.

$ for i in {1..100}; do curl canary.abc.com; done
nginx-prod
nginx-prod
nginx-prod
nginx-prod
nginx-prod
...

I have the impression the TrafficSplit is being ignored by Ingress for some reason. Any suggestion how to do that?

[adleong]

Hi @lucasgrvarela! Traffic splitting is done on the client side, which means it only happens when the client is meshed. This is why you'll see it working for internal traffic (where the client is a meshed pod) but not for external traffic (where the client is outside the cluster).

[lucasgrvarela]

Hi @adleong thank you for the answer.