一、前言
Ingress與Ingress-controller
ingress對象:
指的是k8s中的一個api對象,一般用於yaml配置,如果集成了kubesphere,可以直接在UI界面上進行創建,其作用就是定義請求如何轉發到service的規則,可以理解爲配置模版
Ingress-controller
具體實現反向代理以及負載均衡的程序,對ingress定義的規則進行解析,根據配置的規則來實現請求轉發,簡單來說,ingress-controller纔是負責具體轉發的組建,通過各種方式將它暴露在集羣入口,外部對集羣的請求流量會先到ingress-controller,而ingress對象是用來告訴ingress-controller該如何轉發請求,比如哪些哪些域名path路徑要轉發哪些服務等等
本章採用DaemonSet結合NodeSelector來部署Ingress-controller到特定的node節點上,然後使用HostNetwork直接 把該pod與宿主機node節點的網路打通,直接使用宿主機的80/443端口就能訪問服務
此時,ingress-controller所在的node機器就很類似於傳統架構的邊緣節點,比如機房入口的nginx服務器,該方式整個請求鏈路都很簡單,性能相對NodePort模式更好,缺點就是由於直接利用宿主機節點的網絡和端口,一個node只能部署一個ingress-controller pod,比較適合大併發的生產環境使用
首先給指定的node節點打上標籤,讓我們的ingress-controller根據標籤運行在指定的節點上,在這裏我們選擇k8s-node02節點
[root@k8s-master01 ingress]# kubectl label node k8s-node02 ingress=true
[root@k8s-master01 ingress]# kubectl get nodes --show-labels
部署nginx-ingress-controller
該mandatory.yaml文件中包含了很多資源的創建,例如namespace、Configmap、role、ServiceAccount等等所有部署ingress-controller需要的資源
#wget https://raw.githubusercontent.com/kubernetes/ingress-nginx/nginx-0.25.0/deploy/static/mandatory.yaml
對nginx-ingress-controller的yaml文件根據業務情況進行修改,在這改動的是ClusterRole資源配置、修改控制器類型爲DaemonSet,並開啓hostNetwork網絡
#vim /opt/ingress/mandatory.yaml
apiVersion: v1 kind: Namespace metadata: name: ingress-nginx labels: app.kubernetes.io/name: ingress-nginx app.kubernetes.io/part-of: ingress-nginx --- kind: ConfigMap apiVersion: v1 metadata: name: nginx-configuration namespace: ingress-nginx labels: app.kubernetes.io/name: ingress-nginx app.kubernetes.io/part-of: ingress-nginx --- kind: ConfigMap apiVersion: v1 metadata: name: tcp-services namespace: ingress-nginx labels: app.kubernetes.io/name: ingress-nginx app.kubernetes.io/part-of: ingress-nginx --- kind: ConfigMap apiVersion: v1 metadata: name: udp-services namespace: ingress-nginx labels: app.kubernetes.io/name: ingress-nginx app.kubernetes.io/part-of: ingress-nginx --- apiVersion: v1 kind: ServiceAccount metadata: name: nginx-ingress-serviceaccount namespace: ingress-nginx labels: app.kubernetes.io/name: ingress-nginx app.kubernetes.io/part-of: ingress-nginx --- apiVersion: rbac.authorization.k8s.io/v1beta1 kind: ClusterRole metadata: name: nginx-ingress-clusterrole labels: app.kubernetes.io/name: ingress-nginx app.kubernetes.io/part-of: ingress-nginx rules: - apiGroups: - "" resources: - configmaps - endpoints - nodes - pods - secrets verbs: - list - watch - apiGroups: - "" resources: - nodes verbs: - get - apiGroups: - "" resources: - services verbs: - get - list - watch - apiGroups: - "extensions" - "networking.k8s.io" #nginx-ingress-controller:0.25版本增加network.k8s.io Ingress資源api resources: - ingresses verbs: - get - list - watch - apiGroups: - "" resources: - events verbs: - create - patch - apiGroups: - "extensions" - "networking.k8s.io" ##nginx-ingress-controller:0.25版本增加network.k8s.io Ingress資源api resources: - ingresses/status verbs: - update --- apiVersion: rbac.authorization.k8s.io/v1beta1 kind: Role metadata: name: nginx-ingress-role namespace: ingress-nginx labels: app.kubernetes.io/name: ingress-nginx app.kubernetes.io/part-of: ingress-nginx rules: - apiGroups: - "" resources: - configmaps - pods - secrets - namespaces verbs: - get - apiGroups: - "" resources: - configmaps resourceNames: # Defaults to "<election-id>-<ingress-class>" # Here: "<ingress-controller-leader>-<nginx>" # This has to be adapted if you change either parameter # when launching the nginx-ingress-controller. - "ingress-controller-leader-nginx" verbs: - get - update - apiGroups: - "" resources: - configmaps verbs: - create - apiGroups: - "" resources: - endpoints verbs: - get --- apiVersion: rbac.authorization.k8s.io/v1beta1 kind: RoleBinding metadata: name: nginx-ingress-role-nisa-binding namespace: ingress-nginx labels: app.kubernetes.io/name: ingress-nginx app.kubernetes.io/part-of: ingress-nginx roleRef: apiGroup: rbac.authorization.k8s.io kind: Role name: nginx-ingress-role subjects: - kind: ServiceAccount name: nginx-ingress-serviceaccount namespace: ingress-nginx --- apiVersion: rbac.authorization.k8s.io/v1beta1 kind: ClusterRoleBinding metadata: name: nginx-ingress-clusterrole-nisa-binding labels: app.kubernetes.io/name: ingress-nginx app.kubernetes.io/part-of: ingress-nginx roleRef: apiGroup: rbac.authorization.k8s.io kind: ClusterRole name: nginx-ingress-clusterrole subjects: - kind: ServiceAccount name: nginx-ingress-serviceaccount namespace: ingress-nginx --- apiVersion: apps/v1 #kind: Deployment kind: DaemonSet #將nginx-ingress-controller部署爲Daemonset metadata: name: nginx-ingress-controller namespace: ingress-nginx labels: app.kubernetes.io/name: ingress-nginx app.kubernetes.io/part-of: ingress-nginx spec: # replicas: 1 #因爲DaemonSet沒有副本機制的概念,因此這裏需要將其註釋 selector: matchLabels: app.kubernetes.io/name: ingress-nginx app.kubernetes.io/part-of: ingress-nginx template: metadata: labels: app.kubernetes.io/name: ingress-nginx app.kubernetes.io/part-of: ingress-nginx annotations: prometheus.io/port: "10254" prometheus.io/scrape: "true" spec: hostNetwork: true #開啓hostNetwork網絡,讓其使用宿主機節點的端口 nodeSelector: #配置nodeSelector標籤選擇器 ingress: "true" serviceAccountName: nginx-ingress-serviceaccount containers: - name: nginx-ingress-controller image: quay.io/kubernetes-ingress-controller/nginx-ingress-controller:0.25.0 args: - /nginx-ingress-controller - --configmap=$(POD_NAMESPACE)/nginx-configuration - --tcp-services-configmap=$(POD_NAMESPACE)/tcp-services - --udp-services-configmap=$(POD_NAMESPACE)/udp-services - --publish-service=$(POD_NAMESPACE)/ingress-nginx - --annotations-prefix=nginx.ingress.kubernetes.io securityContext: allowPrivilegeEscalation: true capabilities: drop: - ALL add: - NET_BIND_SERVICE # www-data -> 33 runAsUser: 33 env: - name: POD_NAME valueFrom: fieldRef: fieldPath: metadata.name - name: POD_NAMESPACE valueFrom: fieldRef: fieldPath: metadata.namespace ports: - name: http containerPort: 80 - name: https containerPort: 443 livenessProbe: failureThreshold: 3 httpGet: path: /healthz port: 10254 scheme: HTTP initialDelaySeconds: 10 periodSeconds: 10 successThreshold: 1 timeoutSeconds: 10 readinessProbe: failureThreshold: 3 httpGet: path: /healthz port: 10254 scheme: HTTP periodSeconds: 10 successThreshold: 1 timeoutSeconds: 10 ---
[root@k8s-master01 ingress]# kubectl apply -f mandatory.yaml
[root@k8s-master01 ~]# kubectl get pod -n ingress-nginx -o wide NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES nginx-ingress-controller-j4wq8 1/1 Running 0 20m 192.168.126.135 k8s-node02 <none> <none> [root@k8s-master01 ~]# kubectl get cm,daemonset -n ingress-nginx -o wide NAME DATA AGE configmap/ingress-controller-leader-nginx 0 17m configmap/kube-root-ca.crt 1 20m configmap/nginx-configuration 0 20m configmap/tcp-services 0 20m configmap/udp-services 0 20m NAME DESIRED CURRENT READY UP-TO-DATE AVAILABLE NODE SELECTOR AGE CONTAINERS IMAGES SELECTOR daemonset.apps/nginx-ingress-controller 1 1 1 1 1 ingress=true 20m nginx-ingress-controller quay.io/kubernetes-ingress-controller/nginx-ingress-controller:0.25.0 app.kubernetes.io/name=ingress-nginx,app.kubernetes.io/part-of=ingress-nginx
在ingres-ingress-controller所在的node2節點上查看監聽的端口以及容器服務
[root@k8s-node02 ~]# netstat -antp | grep nginx
創建Ingress規則
這裏我們啓動了兩個nginx pod作爲後端的應用服務,以及指定暴露出service
[root@k8s-master01 ingress]# vim service-nginx.yaml
apiVersion: apps/v1 kind: Deployment metadata: name: nginx-app spec: replicas: 3 selector: matchLabels: app: nginx template: metadata: labels: app: nginx spec: containers: - name: nginx image: nginx imagePullPolicy: IfNotPresent ports: - containerPort: 80 --- apiVersion: v1 kind: Service metadata: name: nginx-app-svc spec: type: ClusterIP ports: - protocol: TCP port: 80 targetPort: 80 selector: app: nginx
#[root@k8s-master01 ingress]# kubectl get -f service-nginx.yaml
創建Ingress服務,
#vim ingressp-app.yaml
apiVersion: networking.k8s.io/v1 kind: Ingress metadata: name: nginx-app-ingress spec: rules: - host: www.test.com http: paths: - path: / pathType: Prefix backend: service: name: nginx-app-svc #指定svc名稱 port: number: 80
#kubectl apply -f ingressp-app.yaml
驗證測試
在本地PC端配置一個host解析,測試訪問
假設我們需要給指定的域名加上https認證,那麼該如何實現呢?
首先我們需要導入tsl證書,創建類型爲tsl的secret, 將我們的證書和密鑰導入進去
創建Secret
[root@k8s-master01 tsl]# kubectl create secret tls jiicm-com --key server.key --cert jiicm.com.crt
查看詳情
配置ingres
#vim ingressp-app.yaml
apiVersion: networking.k8s.io/v1 kind: Ingress metadata: name: nginx-app-ingress spec: tls: - hosts: - ts.jiicm.com #指定https域名 secretName: jiicm-com #指定類型爲tls的secret名稱(也就是上面我們創建的ssl證書) rules: - host: ts.jiicm.com http: paths: - path: / pathType: Prefix #路徑的匹配方式,目前有implementationSpecific、Exact和Prefix方式 backend: service: name: nginx-app-svc #指定後端nginx服務的service名稱 port: number: 80
#kubectl replace -f ingressp-app.yaml
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