Вы можете попробовать использовать службу типа ExternalName вот так:
kind: Service
apiVersion: v1
metadata:
name: s3-ap-south
spec:
type: ExternalName
externalName: s3.ap-south-1.amazonaws.com
---
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
name: s3-ingress
annotations:
kubernetes.io/ingress.class: "nginx"
nginx.ingress.kubernetes.io/backend-protocol: "HTTPS"
nginx.ingress.kubernetes.io/ssl-passthrough: "true"
spec:
rules:
- host: YOUR_HOSTNAME
http:
paths:
- backend:
serviceName: s3-ap-south
servicePort: 443