coredns部署

coredns部署

一：coredns-rbac.yaml

apiVersion: v1
kind: ServiceAccount
metadata:name: corednsnamespace: kube-systemlabels:kubernetes.io/cluster-service: "true"addonmanager.kubernetes.io/mode: Reconcile
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:labels:kubernetes.io/bootstrapping: rbac-defaultsaddonmanager.kubernetes.io/mode: Reconcilename: system:coredns
rules:
- apiGroups:- ""resources:- endpoints- services- pods- namespacesverbs:- list- watch
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:annotations:rbac.authorization.kubernetes.io/autoupdate: "true"labels:kubernetes.io/bootstrapping: rbac-defaultsaddonmanager.kubernetes.io/mode: EnsureExistsname: system:coredns
roleRef:apiGroup: rbac.authorization.k8s.iokind: ClusterRolename: system:coredns
subjects:
- kind: ServiceAccountname: corednsnamespace: kube-system

kubectl create -f coredns-rbac.yaml

二：coredns-configmap.yaml

apiVersion: v1
kind: ConfigMap
metadata:name: corednsnamespace: kube-system
data:Corefile: |.:53 {errorsloghealthreadykubernetes cluster.local 10.8.0.0/16  #service资源cluster地址forward . 192.168.10.2   #上级DNS地址cache 30loopreloadloadbalance}

kubectl create -f coredns-configmap.yaml

三：coredns-deployment.yaml

apiVersion: apps/v1
kind: Deployment
metadata:name: corednsnamespace: kube-systemlabels:k8s-app: corednskubernetes.io/name: "CoreDNS"
spec:replicas: 1selector:matchLabels:k8s-app: corednstemplate:metadata:labels:k8s-app: corednsspec:priorityClassName: system-cluster-criticalserviceAccountName: corednscontainers:- name: corednsimage: docker.io/coredns/coredns args:- -conf- /etc/coredns/CorefilevolumeMounts:- name: config-volumemountPath: /etc/corednsports:- containerPort: 53name: dnsprotocol: UDP- containerPort: 53name: dns-tcpprotocol: TCP- containerPort: 9153name: metricsprotocol: TCPlivenessProbe:httpGet:path: /healthport: 8080scheme: HTTPinitialDelaySeconds: 60timeoutSeconds: 5successThreshold: 1failureThreshold: 5dnsPolicy: Defaultvolumes:- name: config-volumeconfigMap:name: corednsitems:- key: Corefilepath: Corefile

kubectl create -f coredns-deployment.yaml

四：coredns-svc.yaml

apiVersion: v1
kind: Service
metadata:name: corednsnamespace: kube-systemlabels:k8s-app: corednskubernetes.io/cluster-service: "true"kubernetes.io/name: "CoreDNS"
spec:selector:k8s-app: corednsclusterIP: 10.8.0.2ports:- name: dnsport: 53protocol: UDP- name: dns-tcpport: 53- name: metricsport: 9153protocol: TCP

kubectl create -f coredns-svc.yaml

五：验证

[root@k3 coredns]# kubectl get all -n kube-system -l k8s-app=coredns

NAME READY STATUS RESTARTS AGE

pod/coredns-5c956578dd-5lmwl 1/1 Running 0 2m9s

NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE

service/coredns ClusterIP 10.8.0.2 53/UDP,53/TCP,9153/TCP 96s

NAME READY UP-TO-DATE AVAILABLE AGE

deployment.apps/coredns 1/1 1 1 2m9s

NAME DESIRED CURRENT READY AGE

replicaset.apps/coredns-5c956578dd 1 1 1 2m9s

[root@k3 coredns]# dig -t A www.baidu.com @192.168.10.2 +short

www.a.shifen.com.

183.232.231.172

183.232.231.174

[root@k3 coredns]# dig -t A www.baidu.com @10.8.0.2 +short

www.a.shifen.com.

183.232.231.172

183.232.231.174

[root@k3 coredns]# kubectl create deployment nginx-dp --image=nginx

deployment.apps/nginx-dp created

[root@k3 coredns]# kubectl get deployments

NAME READY UP-TO-DATE AVAILABLE AGE

nginx-dp 1/1 1 1 9s

[root@k3 coredns]# kubectl get pod

NAME READY STATUS RESTARTS AGE

nginx-dp-6cd9b76579-5dz7t 1/1 Running 0 19s

[root@k3 coredns]# kubectl expose deployment nginx-dp --port=80

service/nginx-dp exposed

[root@k3 coredns]# dig -t A nginx-dp @10.8.0.2 +short

[root@k3 coredns]# dig -t A nginx-dp.default.svc.cluster.local. @10.8.0.2 +short

10.8.223.101

[root@k3 coredns]# kubectl exec -it nginx-dp-6cd9b76579-5dz7t -- cat /etc/resolv.conf

nameserver 10.0.0.2

search default.svc.cluster.local. svc.cluster.local. cluster.local.

options ndots:5

##configmap 解析

 volumes:- name: confconfigMap:name: cm-testitems:- key: index.jsp   #key不能写错，cm文件里定义的就是这个path: index.jsp  #挂载在容器后叫什么文件名