ServersTransport not applied when using Kubernetes Ingress with ingressClass filter

ServersTransport not working with Kubernetes Ingress + ingressClass filter

Traefik version: 3.6.10
Setup: Two Traefik controllers in the same cluster, each scoped with --providers.kubernetescrd.ingressClass=traefik-internal

I'm migrating from Nginx Ingress and need to replicate nginx.ingress.kubernetes.io/backend-protocol: HTTPS. My backend serves HTTPS on port 8080 with a self-signed cert (DNS SANs only, no IP SANs).

Traefik connects directly to pod IPs, so I get:

cannot validate certificate for 10.135.166.114 because it doesn't contain any IP SANs

I cannot use IngressRoute - I'm constrained to standard Kubernetes Ingress resources.

What I tried

1. ServersTransport with insecureSkipVerify: true referenced via:

traefik.ingress.kubernetes.io/service.serverstransport:`` namespace-test-insecure-transport@kubernetescrd

The resource exists in Kubernetes but never appears in /api/http/serverstransports. Silently ignored.

2. Added ingressClass annotation to ServersTransport - no effect.

3. Named Service port https - scheme correctly switches to HTTPS but the IP SAN error persists since ServersTransport isn't loaded.

Questions

  • Is ServersTransport intentionally unsupported with Ingress resources?
  • Is there any supported way to configure insecureSkipVerify for HTTPS backends when using Ingress?
  • Should ServersTransport be exempt from the ingressClass filter since it has no ingressClass field?