How to debug QuotaSpecBinding for rate-limits in istio? - kubernetes

Question

I am trying to enable the rate-limit for my istio enabled service. But it doesn't work. How do I debug if my configuration is correct?
apiVersion: config.istio.io/v1alpha2
kind: memquota
metadata:
name: handler
namespace: istio-system
spec:
quotas:
- name: requestcount.quota.istio-system
maxAmount: 5
validDuration: 1s
overrides:
- dimensions:
engine: myEngineValue
maxAmount: 5
validDuration: 1s
---
apiVersion: config.istio.io/v1alpha2
kind: quota
metadata:
name: requestcount
namespace: istio-system
spec:
dimensions:
source: request.headers["x-forwarded-for"] | "unknown"
destination: destination.labels["app"] | destination.service | "unknown"
destinationVersion: destination.labels["version"] | "unknown"
engine: destination.labels["engine"] | "unknown"
---
apiVersion: config.istio.io/v1alpha2
kind: QuotaSpec
metadata:
name: request-count
namespace: istio-system
spec:
rules:
- quotas:
- charge: 1
quota: requestcount
---
apiVersion: config.istio.io/v1alpha2
kind: QuotaSpecBinding
metadata:
name: request-count
namespace: istio-system
spec:
quotaSpecs:
- name: request-count
namespace: istio-system
services:
# - service: '*' ; I tried with this as well
- name: my-service
namespace: default
---
apiVersion: config.istio.io/v1alpha2
kind: rule
metadata:
name: quota
namespace: istio-system
spec:
actions:
- handler: handler.memquota
instances:
- requestcount.quota
I tried with - service: '*' as well in the QuotaSpecBinding; but no luck.
How, do I confirm if my configuration was correct? the my-service is the kubernetes service for my deployment. (Does this have to be a VirtualService of istio for rate limits to work? Edit: Yes, it has to!)
I followed this doc except the VirtualService part.
I have a feeling somewhere in the namespaces I am doing a mistake.

Answer 1

You have to define the virtual service for the service my-service:
apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
name: myservice
spec:
hosts:
- myservice
http:
- route:
- destination:
host: myservice
This way, you allow Istio to know which service are you host you are referring to.
In terms of debugging, I know that there is a project named Kiali that aims to leverage observability in Istio environments. I know that they have validations for some Istio and Kubernetes objects: Istio configuration browse.