Principle:Kserve Kserve Ingress Routing

Knowledge Sources	Kubernetes Gateway API Istio VirtualService KServe Networking
Domains	Networking, Kubernetes, Service_Mesh
Last Updated	2026-02-13 00:00 GMT

Overview

A networking pattern that maps InferenceService endpoints to externally accessible URLs through Kubernetes ingress resources such as VirtualServices and HTTPRoutes.

Description

Ingress Routing determines how external clients reach InferenceService prediction endpoints. KServe supports multiple ingress backends:

• Istio VirtualService: Routes traffic via Istio ingress gateway with host-based routing.
• Gateway API HTTPRoute: The newer Kubernetes-native gateway routing.
• Knative DomainMapping: When using Knative Serving in serverless mode.

The ingress reconciler constructs the external URL using a domain template (Template:.Name-Template:.Namespace.Template:.IngressDomain) and creates the appropriate routing resources. It also sets the internal cluster address for service-to-service communication.

Usage

This principle is active for every InferenceService deployment. Understanding it is essential for:

• Configuring custom ingress domains
• Debugging connectivity issues
• Setting up TLS termination
• Understanding the URL format for prediction requests

Theoretical Basis

The ingress routing follows a host-based dispatching model:

# Abstract routing flow (NOT implementation code)
External URL format: http://<name>-<namespace>.<ingressDomain>
Internal address:    http://<name>.<namespace>.svc.cluster.local

Routing path:
1. Client sends request to external URL
2. Ingress gateway resolves host header
3. VirtualService/HTTPRoute matches host → routes to Knative Service or ClusterIP
4. Component service handles prediction request

Status fields set by ingress reconciler:
- status.url           → External prediction URL
- status.address       → Cluster-internal address
- components.restURL   → Per-component REST endpoint
- components.grpcURL   → Per-component gRPC endpoint

Related Pages

Implemented By

• Implementation:Kserve_Kserve_IngressReconciler