apiVersion: kyverno.io/v1
kind: ClusterPolicy
metadata:
  name: min-replicas
  annotations:
    policies.kyverno.io/title: Ban single-replica Deployments
    policies.kyverno.io/category: Best Practices
    policies.kyverno.io/severity: medium
    policies.kyverno.io/description: >-
      Audit Deployments whose effective replica count is exactly one. Stopped
      Deployments may use zero, and available Deployments must use at least two
      unless a resource-specific exception is approved.
spec:
  validationFailureAction: Audit
  background: true
  rules:
    - name: min-replicas
      match:
        any:
          - resources:
              kinds:
                - Deployment
      validate:
        message: >-
          Deployment replica count must be zero or at least two. A single
          replica requires a resource-specific PolicyException.
        deny:
          conditions:
            all:
              - key: "{{ request.object.spec.replicas || `1` }}"
                operator: Equals
                value: 1