Istio Traffic Flow

Istio Traffic Flow An architecture diagram generated by Archify. User · External request · Architecture component User External request Gateway · port 80/443 · Architecture component · Ingress Gateway port 80/443 Ingress VirtualService routing · Path · Header · Weight matching · Architecture component · 3 rules VirtualService routing Path · Header · Weight matching 3 rules DestinationRule policies · LB · Circuit breaker · Connection pool · Architecture component · 3 policies DestinationRule policies LB · Circuit breaker · Connection pool 3 policies Pod v1-1 · subset v1 · Pods Pod v1-1 subset v1 Pod v1-2 · subset v1 · Pods Pod v1-2 subset v1 Pod v2-1 · subset v2 · Pods Pod v2-1 subset v2 request select subset Pods Legend Routing rules / workloads Ingress Gateway Traffic policy External user

VirtualService routing

  • • Path matching — choose a route by URI condition
  • • Header matching — expose the new version via headers such as x-dev-user
  • • Weight distribution — canary ratios such as v1 95% / v2 5%

DestinationRule policies

  • • Load balancing — spread requests across the pods in a subset
  • • Circuit breaker — isolate failing pods with outlierDetection
  • • Connection pool — cap connections and pending requests

Pods

  • • Two subset v1 pods and one subset v2 pod (3 replicas total)
  • • After the policies, a request lands on exactly one of them