Implement a canary rollout with Istio VirtualService traffic splitting using Argo Rollouts

Steps

1. Create two Kubernetes Services: one for stable traffic and one for canary traffic, both selecting pods managed by the Rollout via shared labels.
2. Create an Istio VirtualService with an HTTP route containing two weighted destinations—one pointing to the stable Service and one to the canary Service; the initial canary weight can be 0.
3. Create an Istio DestinationRule with two subsets (stable and canary) if using subset-based splitting; reference the subset names in the VirtualService route destinations.
4. Define a Rollout with spec.strategy.canary and a trafficRouting.istio block specifying the virtualService name, the route name within that VirtualService, and optionally the destinationRule with canarySubsetName and stableSubsetName.
5. Add canary steps using setWeight (percentage of traffic to send to canary) and pause (manual gate or duration) to progressively shift traffic; Argo Rollouts updates the VirtualService weights automatically at each step.
6. Monitor the rollout with kubectl argo rollouts get rollout <name> --watch and use kubectl argo rollouts promote to advance past manual pause steps.