Istio traffic routing rules take no effect - istio

Question

I am trying to configure a request routing using Istio and Ingress-nginx but I'm not able to route the requests properly. Basically I have two deployments each as a different subset and implemented a weighted VirtualService.
In Kiali dashboard it shows the request being routed from the ingress-controller to PassthroughCluster even though I can see the correct route mapping using istioctl proxy-config routes command.
Here is the complete configuration:
apiVersion: v1
kind: ServiceAccount
metadata:
name: dummy-app
namespace: my-namespace
---
apiVersion: v1
kind: Service
metadata:
name: dummy-app
namespace: my-namespace
labels:
app: dummy-app
service: dummy-app
spec:
ports:
- port: 8080
targetPort: 8080
name: http-web
selector:
app: dummy-app
---
apiVersion: apps/v1
kind: Deployment
metadata:
name: dummy-app-1
namespace: my-namespace
spec:
replicas: 1
selector:
matchLabels:
app: dummy-app
version: v1
template:
metadata:
annotations:
sidecar.istio.io/inject: "true"
labels:
app: dummy-app
version: v1
spec:
serviceAccountName: dummy-app
containers:
- image: my-img
imagePullPolicy: IfNotPresent
name: dummy-app
env:
- name: X_HTTP_ENV
value: dummy-app-1
ports:
- containerPort: 8080
---
apiVersion: apps/v1
kind: Deployment
metadata:
name: dummy-app-2
namespace: my-namespace
spec:
replicas: 1
selector:
matchLabels:
app: dummy-app
version: v2
template:
metadata:
annotations:
sidecar.istio.io/inject: "true"
labels:
app: dummy-app
version: v2
spec:
serviceAccountName: dummy-app
containers:
- image: my-img
imagePullPolicy: IfNotPresent
name: dummy-app
env:
- name: X_HTTP_ENV
value: dummy-app-2
ports:
- containerPort: 8080
---
apiVersion: networking.istio.io/v1alpha3
kind: DestinationRule
metadata:
name: dummy-app
namespace: my-namespace
spec:
host: dummy-app
subsets:
- name: v1
labels:
version: v1
- name: v2
labels:
version: v2
---
apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
name: dummy-app
namespace: my-namespace
spec:
hosts:
- dummy-app.my-namespace.svc.cluster.local
http:
- match:
- uri:
prefix: "/my-route"
route:
- destination:
host: dummy-app.my-namespace.svc.cluster.local
subset: v1
weight: 0
- destination:
host: dummy-app.my-namespace.svc.cluster.local
subset: v2
weight: 100
---
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
annotations:
kubernetes.io/ingress.class: "my-ingress-class"
nginx.ingress.kubernetes.io/service-upstream: "true"
nginx.ingress.kubernetes.io/upstream-vhost: dummy-app.my-namespace.svc.cluster.local
name: dummy-ingress
namespace: my-namespace
spec:
rules:
- host: myapp.com
http:
paths:
- backend:
service:
name: dummy-app
port:
number: 8080
path: /my-route(.*)
pathType: ImplementationSpecific
Weird thing is I have other applications working in the same namespace and using the same ingress-controller, so I'm not considering there is a problem with ingress-nginx setup.
Istio version:
client version: 1.11.4
control plane version: 1.11.4
data plane version: 1.11.4 (13 proxies), 1.12-dev (15 proxies)
Any ideas on what is the configuration problem or how can I better debug these kind of issues in Istio?

Answer 1

Main issue seems to be with ingress-nginx resource. Based on the above ingress definition, you are trying to bypass istio ingress gateway (where all the proxying rules has been implemented, like gateway,virtual-service and destination rules) and directly pushing the traffic to the application service from ingress. For istio proxy rules to work, you should let traffic pass through istio-ingressgateway (a service under istio-system namespace). So following changes should be made to your ingress resource:
rules:
- host: myapp.com
http:
paths:
- backend:
service:
name: istio-ingressgateway.istio-system
port:
number: 80
path: /my-route(.*)
pathType: ImplementationSpecific