NSG rule not created when setting IPv6 single stack allowed source range in v1.26 and v1.25

[zarvd]

What happened:

apiVersion: v1
kind: Service
metadata:
  name: foo
spec:
  type: LoadBalancer
  selector:
    app: foo
  ipFamilies:
  - IPv6
  ipFamilyPolicy: SingleStack
  loadBalancerSourceRanges:
  - fd00::/8
  ports:
  - name: https
    port: 443
    protocol: TCP
    targetPort: 443

When applying the above manifest, the NSG rule was not created as expected.

What you expected to happen:

An NSG rule for IPv6 was created.

How to reproduce it (as minimally and precisely as possible):

Anything else we need to know?:

It's a bug exposed in #5123 that doesn’t properly handle the scenario of a single IPv6 stack.

Environment:

• Kubernetes version (use kubectl version): v1.26 / v1.25
• Cloud provider or hardware configuration:
• OS (e.g: cat /etc/os-release):
• Kernel (e.g. uname -a):
• Install tools:
• Network plugin and version (if this is a network-related bug):
• Others:

[zarvd]

/assign

[zarvd]

fixed via #5367