Kubernetes网络隔离NetworkPolicy实验

Kubernetes的一个重要特性就是要把不同node节点的pod（container）连接起来，无视物理节点的限制。但是在某些应用环境中，比如公有云，不同租户的pod不应该互通，这个时候就需要网络隔离。幸好，Kubernetes提供了NetworkPolicy，支持按Namespace级别的网络隔离。

使用NetworkPolicy需要kubernetes1.8以及calico2.6.2。

实验步骤 1.创建两个namespace: ns-calico1、ns-calico2 2.分别在两个namespace下创建应用： ns-calico1下面创建三个应用

ns-calico1下的calico1-busybox应用：

apiVersion: extensions/v1beta1 kind: Deployment metadata: name: calico1-busybox namespace: ns-calico1 spec: replicas: 1 template: metadata: labels: user: calico1 app: calico1-busybox spec: containers: -name:calico1-busyboximage: busybox imagePullPolicy: IfNotPresent command: -sleep-"3600"

ns-calico1下的calico1-nginx应用：

apiVersion: extensions/v1beta1 kind: Deployment metadata:name: calico1-nginxnamespace: ns-calico1spec:replicas: 1template:metadata:labels:user: calico1app: calico1-nginxspec:containers:- name: calico1-nginximage: nginxports:- containerPort: 80 ---apiVersion: v1 kind: Service metadata:name: calico1-nginxnamespace: ns-calico1labels:user: calico1spec:selector:app: calico1-nginxports:- port: 80

ns-calico1下的calico1-nginx2应用：

apiVersion: extensions/v1beta1 kind: Deployment metadata:name: calico1-nginx2namespace: ns-calico1spec:replicas: 1template:metadata:labels:user: calico1app: calico1-nginx2spec:containers:- name: calico1-nginx2image: nginxports:- containerPort: 80 ---apiVersion: v1 kind: Service metadata:name: calico1-nginx2namespace: ns-calico1labels:user: calico1spec:selector:app: calico1-nginx2ports:- port: 80ns-

calico2下面创建一个应用

ns-calico2下的calico2-busybox应用：

apiVersion: extensions/v1beta1 kind: Deployment metadata: name: calico2-busybox namespace: ns-calico2 spec: replicas: 1 template: metadata: labels: user: calico2 app: calico2-busybox spec: containers: -name:calico2-busyboximage: busybox imagePullPolicy: IfNotPresent command: -sleep-"3600"

3.测试

3.1加策略前

测试结果

kubectl exec-itcalico1-busybox-5f4d7d5f4-n7qjg-nns-calico1--wget--spider--timeout=1calico1-nginx.ns-calico1Connectingtocalico1-nginx.ns-calico1(10.233.30.47:80) 通 kubectl exec-itcalico2-busybox-6dd875d4f-8747j-nns-calico2--wget--spider--timeout=1calico1-nginx.ns-calico1Connectingtocalico1-nginx.ns-calico1(10.233.30.47:80) 通

结论：加策略前，同namespace以及跨namespace的应用之间都是互通的

3.2加策略后，应用未打标签前

策略文件：

kind:NetworkPolicyapiVersion:networking.k8s.io/v1metadata:name: access-nginx namespace: ns-calico1spec:podSelector: matchLabels: app: calico1-nginx ingress: - from: - podSelector: matchLabels: access:"true"

说明：该策略只允许有access: “true”标签的应用访问ns-calico1下面有app: calico1-nginx标签的应用，即我们的测试应用

测试结果

kubectl exec-itcalico1-busybox-5f4d7d5f4-n7qjg-nns-calico1--wget--spider--timeout=1calico1-nginx.ns-calico1Connectingtocalico1-nginx.ns-calico1(10.233.30.47:80) wget: download timed out 不通 kubectl exec-itcalico2-busybox-6dd875d4f-8747j-nns-calico2--wget--spider--timeout=1calico1-nginx.ns-calico1Connectingtocalico1-nginx.ns-calico1(10.233.30.47:80) wget: download timed out 不通 kubectl exec-itcalico1-busybox-5f4d7d5f4-n7qjg-nns-calico1--wget--spider--timeout=1calico1-nginx2.ns-calico1Connectingtocalico1-nginx2.ns-calico1(10.233.23.44:80) 通 kubectl exec-itcalico2-busybox-6dd875d4f-8747j-nns-calico2--wget--spider--timeout=1calico1-nginx2.ns-calico1Connectingtocalico1-nginx2.ns-calico1(10.233.23.44:80) 通