目的

使用CoreDNS实现对k8s内部域名解析

说明

这部分使用CoreDNS
群集域名： cluster.local 地址：10.254.0.0/16 群集服务地址： 10.254.0.10

创建coreDNS 的sa,rbac,Deployment和svc，文件为：Coredns.yaml

  1. apiVersion: v1
  2. kind: ServiceAccount
  3. metadata:
  4.   name: kubernetes
  5.   namespace: kube-system
  6. ---
  7. apiVersion: rbac.authorization.k8s.io/v1beta1
  8. kind: ClusterRole
  9. metadata:
  10.   labels:
  11.     kubernetes.io/bootstrapping: rbac-defaults
  12.   name: system:kubernetes
  13. rules:
  14. - apiGroups:
  15.   - ""
  16.   resources:
  17.   - endpoints
  18.   - services
  19.   - pods
  20.   - nodes
  21.   - namespaces
  22.   verbs:
  23.   - get
  24.   - list
  25.   - watch
  26. ---
  27. apiVersion: rbac.authorization.k8s.io/v1beta1
  28. kind: ClusterRoleBinding
  29. metadata:
  30.   annotations:
  31.     rbac.authorization.kubernetes.io/autoupdate: "true"
  32.   labels:
  33.     kubernetes.io/bootstrapping: rbac-defaults
  34.   name: system:kubernetes
  35. roleRef:
  36.   apiGroup: rbac.authorization.k8s.io
  37.   kind: ClusterRole
  38.   name: system:kubernetes
  39. subjects:
  40. - kind: ServiceAccount
  41.   name: kubernetes
  42.   namespace: kube-system
  43. ---
  44. apiVersion: v1
  45. kind: ConfigMap
  46. metadata:
  47.   name: coredns
  48.   namespace: kube-system
  49. data:
  50.   Corefile: |
  51.     .:53 {
  52.         errors
  53.         health
  54.         kubernetes cluster.local 10.254.0.0/16 {
  55.           #pods insecure
  56.           upstream /etc/resolv.conf
  57.         }
  58.         prometheus :9153
  59.         proxy . /etc/resolv.conf
  60.         cache 30
  61.     }
  62. ---
  63. apiVersion: extensions/v1beta1
  64. kind: Deployment
  65. metadata:
  66.   name: coredns
  67.   namespace: kube-system
  68.   labels:
  69.     k8s-app: coredns
  70.     kubernetes.io/name: "CoreDNS"
  71. spec:
  72.   replicas: 2
  73.   strategy:
  74.     type: RollingUpdate
  75.     rollingUpdate:
  76.       maxUnavailable: 1
  77.   selector:
  78.     matchLabels:
  79.       k8s-app: coredns
  80.   template:
  81.     metadata:
  82.       labels:
  83.         k8s-app: coredns
  84.     spec:
  85.       serviceAccountName: kubernetes
  86.       tolerations:
  87.         - key: node-role.kubernetes.io/master
  88.           effect: NoSchedule
  89.         - key: "CriticalAddonsOnly"
  90.           operator: "Exists"
  91.       containers:
  92.       - name: coredns
  93.         image: hub.k8s.com/apps/coredns:1.0.3
  94.         imagePullPolicy: IfNotPresent
  95.         args: [ "-conf", "/etc/coredns/Corefile" ]
  96.         volumeMounts:
  97.         - name: config-volume
  98.           mountPath: /etc/coredns
  99.         ports:
  100.         - containerPort: 53
  101.           name: dns
  102.           protocol: UDP
  103.         - containerPort: 53
  104.           name: dns-tcp
  105.           protocol: TCP
  106.         livenessProbe:
  107.           httpGet:
  108.             path: /health
  109.             port: 8080
  110.             scheme: HTTP
  111.           initialDelaySeconds: 60
  112.           timeoutSeconds: 5
  113.           successThreshold: 1
  114.           failureThreshold: 5
  115.       dnsPolicy: Default
  116.       volumes:
  117.         - name: config-volume
  118.           configMap:
  119.             name: coredns
  120.             items:
  121.             - key: Corefile
  122.               path: Corefile
  123. ---
  124. apiVersion: v1
  125. kind: Service
  126. metadata:
  127.   name: kube-dns
  128.   namespace: kube-system
  129.   labels:
  130.     k8s-app: coredns
  131.     kubernetes.io/cluster-service: "true"
  132.     kubernetes.io/name: "CoreDNS"
  133. spec:
  134.   selector:
  135.     k8s-app: coredns
  136.   clusterIP: 10.254.0.10
  137.   ports:
  138.   - name: dns
  139.     port: 53
  140.     protocol: UDP
  141.   - name: dns-tcp
  142.     port: 53
  143.     protocol: TCP

验证