基于 kubeadm 搭建高可用的kubernetes 1.18.2 (k8s)集群 三 集群可用性测试

1. 创建nginx ds

# 写入配置
$ cat > nginx-ds.yml <<EOF
apiVersion: v1
kind: Service
metadata:
  name: nginx-ds
  labels:
    app: nginx-ds
spec:
  type: NodePort
  selector:
    app: nginx-ds
  ports:
  - name: http
    port: 80
    targetPort: 80
---
apiVersion: apps/v1
kind: DaemonSet
metadata:
  name: nginx-ds
  labels:
    addonmanager.kubernetes.io/mode: Reconcile
spec:
  selector:
    matchLabels:
      app: nginx-ds
  template:
    metadata:
      labels:
        app: nginx-ds
    spec:
      containers:
      - name: my-nginx
        image: nginx:1.17
        ports:
        - containerPort: 80
EOF

# 创建ds
$ kubectl create -f nginx-ds.yml

2. 检查各种ip连通性

# 检查各 Node 上的 Pod IP 连通性
$ kubectl get pods  -o wide

# 在每个节点上ping pod ip
$ ping <pod-ip>

# 检查service可达性
$ kubectl get svc

# 在每个节点上访问服务
$ curl <service-ip>:<port>

# 在每个节点检查node-port可用性
$ curl <node-ip>:<port>

3. 检查dns可用性

# 创建一个nginx pod
$ cat > pod-nginx.yaml <<EOF
apiVersion: v1
kind: Pod
metadata:
  name: nginx
spec:
  containers:
  - name: nginx
    image: nginx:1.17
    ports:
    - containerPort: 80
EOF

# 创建pod
$ kubectl create -f pod-nginx.yaml

# 进入pod，查看dns
$ kubectl exec  nginx -i -t -- /bin/bash

# 查看dns配置
:/# cat /etc/resolv.conf

# 查看名字是否可以正确解析
:/# ping nginx-ds