# Kubernetes Network Policy
###### tags: `NTUToolmenLab`
intro https://kubernetes.io/docs/tasks/administer-cluster/declare-network-policy/

more detail https://kubernetes.io/docs/concepts/services-networking/network-policies/

example https://github.com/ahmetb/kubernetes-network-policy-recipes

spce https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.14/#networkpolicy-v1-networking-k8s-io

My target: allow all egress except to cluster (Not include DNS)

My pods ip are in `10.90.0.0/16`

apiVersion: networking.k8s.io/v1
kind: NetworkPolicy
metadata:
  name: user-policy
  namespace: user
spec:
  podSelector:
    matchLabels:
      yourapp: your app name
  policyTypes:
  - Egress
  egress:
  - to:
    - ipBlock:
        cidr: 0.0.0.0/0
        except: 
        - 10.90.0.0/16
  - ports:
    - port: 53
      protocol: UDP 
    - port: 53
      protocol: TCP