Bootstrap

2024-09-01 - 分布式集群网关 - LoadBalancer - 阿里篇 - 流雨声

摘要

通过公有云部署创建类似 MateLB 的应用负载,可以更加方便的对系统资源进行合理规划。

应用实践

CCM提供Kubernetes与阿里云基础产品(例如CLB、VPC等)对接的能力,支持在同一个CLB后端挂载集群内节点和集群外服务器,可以解决迁移过程中流量中断的难题,同时还支持将业务流量转发至多个Kubernetes集群,实现备份、容灾等需求,从而保障业务的高可用。本文介绍如何在自建的Kubernetes集群中部署CCM。

1. 前提条件
  • 自建Kubernetes集群中已部署VNode。

  • 如果您的Kubernetes集群部署在线下IDC,请确保已打通IDC与阿里云的网络。

2. 背景信息

CCM(Cloud Controller Manager)是阿里云提供的一个用于Kubernetes与阿里云基础产品进行对接的组件,目前包括以下功能:

  • 管理负载均衡

当Service的类型设置为LoadBalancer时,CCM组件会为该Service创建并配置阿里云负载均衡CLB,包括CLB实例、监听、后端服务器组等资源。当Service对应的后端Endpoint或者集群节点发生变化时,CCM会自动更新CLB的后端服务器组。

  • 实现跨节点通信

当集群网络组件为Flannel时,CCM组件负责打通容器与节点间网络,将节点的Pod网段信息写入VPC的路由表中,从而实现容器的跨节点通信。该功能无需配置,安装即可使用。

3. 准备工作

如果您自建的Kubernetes集群中没有使用阿里云ECS作为节点,可跳过准备工作。如果使用了ECS作为集群节点,需要参考以下步骤配置ECS节点的providerID,使得CCM可以管理这些节点的路由。

a. 部署OpenKurise以便使用BroadcastJob。

helm repo add openkruise https://openkruise.github.io/charts/
helm repo update
helm install kruise openkruise/kruise --version 1.3.0

b. 通过BroadcastJob为ECS节点配置providerID

# 将以下内容保存为provider.yaml
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
  name: ecs-node-initor
rules:
  - apiGroups:
      - ""
    resources:
      - nodes
    verbs:
      - get
      - patch
---
apiVersion: v1
kind: ServiceAccount
metadata:
  name: ecs-node-initor
---
kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: ecs-node-initor
subjects:
- kind: ServiceAccount
  name: ecs-node-initor
  namespace: default
roleRef:
  kind: ClusterRole
  name: ecs-node-initor
  apiGroup: rbac.authorization.k8s.io
---
apiVersion: apps.kruise.io/v1alpha1
kind: BroadcastJob
metadata:
  name: create-ecs-node-provider-id
spec:
  template:
    spec:
      serviceAccount: ecs-node-initor
      restartPolicy: OnFailure
      affinity:
        nodeAffinity:
          requiredDuringSchedulingIgnoredDuringExecution:
            nodeSelectorTerms:
            - matchExpressions:
              - key: type
                operator: NotIn
                values:
                - virtual-kubelet
      tolerations:
      - operator: Exists
      containers:
        - name: create-ecs-node-provider-id
          image: registry.cn-beijing.aliyuncs.com/eci-release/provider-initor:v1
          command: [ "/usr/bin/init" ]
          env:
          - name: NODE_NAME
            valueFrom:
              fieldRef:
                fieldPath: spec.nodeName
  completionPolicy:
    type: Never
  failurePolicy:
    type: FailFast
    restartLimit: 3
# 部署BroadcastJob
kubectl apply -f provider.yaml

# 查看BroadcastJob执行结果
kubectl get pods -o wide
4. 操作步骤

a. 创建ConfigMap

#!/bin/bash

# 给账户分配 VPC 和 SLB 权限
export ACCESS_KEY_ID=LTAI********************
export ACCESS_KEY_SECRET=HAeS**************************

## create ConfigMap kube-system/cloud-config for CCM.
accessKeyIDBase64=`echo -n "$ACCESS_KEY_ID" |base64 -w 0`
accessKeySecretBase64=`echo -n "$ACCESS_KEY_SECRET"|base64 -w 0`

cat <<EOF >cloud-config.yaml
apiVersion: v1
kind: ConfigMap
metadata:
  name: cloud-config
  namespace: kube-system
data:
  cloud-config.conf: |-
    {
        "Global": {
            "accessKeyID": "$accessKeyIDBase64",
            "accessKeySecret": "$accessKeySecretBase64",
            "region": "cn-hangzhou"
        }
    }
EOF

kubectl create -f cloud-config.yaml

b. 生成系统配置

bash configmap-ccm.sh

c. 部署CCM

# 您可以通过kubectl cluster-info dump | grep -m1 cluster-cidr命令查看ClusterCIDR
ClusterCIDR=$(kubectl cluster-info dump | grep -m1 cluster-cidr)
ImageVersion=v2.1.0

### ccm.yaml
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
  name: system:cloud-controller-manager
rules:
  - apiGroups:
      - coordination.k8s.io
    resources:
      - leases
    verbs:
      - get
      - list
      - update
      - create
  - apiGroups:
      - ""
    resources:
      - persistentvolumes
      - services
      - secrets
      - endpoints
      - serviceaccounts
    verbs:
      - get
      - list
      - watch
      - create
      - update
      - patch
  - apiGroups:
      - ""
    resources:
      - nodes
    verbs:
      - get
      - list
      - watch
      - delete
      - patch
      - update
  - apiGroups:
      - ""
    resources:
      - services/status
    verbs:
      - update
      - patch
  - apiGroups:
      - ""
    resources:
      - nodes/status
    verbs:
      - patch
      - update
  - apiGroups:
      - ""
    resources:
      - events
      - endpoints
    verbs:
      - create
      - patch
      - update
---
apiVersion: v1
kind: ServiceAccount
metadata:
  name: cloud-controller-manager
  namespace: kube-system
---
kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: system:cloud-controller-manager
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: system:cloud-controller-manager
subjects:
  - kind: ServiceAccount
    name: cloud-controller-manager
    namespace: kube-system
---
kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: system:shared-informers
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: system:cloud-controller-manager
subjects:
  - kind: ServiceAccount
    name: shared-informers
    namespace: kube-system
---
kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: system:cloud-node-controller
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: system:cloud-controller-manager
subjects:
  - kind: ServiceAccount
    name: cloud-node-controller
    namespace: kube-system
---
kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: system:pvl-controller
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: system:cloud-controller-manager
subjects:
  - kind: ServiceAccount
    name: pvl-controller
    namespace: kube-system
---
kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: system:route-controller
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: system:cloud-controller-manager
subjects:
  - kind: ServiceAccount
    name: route-controller
    namespace: kube-system
---
apiVersion: apps/v1
kind: DaemonSet
metadata:
  labels:
    app: cloud-controller-manager
    tier: control-plane
  name: cloud-controller-manager
  namespace: kube-system
spec:
  selector:
    matchLabels:
      app: cloud-controller-manager
      tier: control-plane
  template:
    metadata:
      labels:
        app: cloud-controller-manager
        tier: control-plane
      annotations:
        scheduler.alpha.kubernetes.io/critical-pod: ''
    spec:
      serviceAccountName: cloud-controller-manager
      tolerations:
        - effect: NoSchedule
          operator: Exists
          key: node-role.kubernetes.io/master
        - effect: NoSchedule
          operator: Exists
          key: node.cloudprovider.kubernetes.io/uninitialized
      nodeSelector:
        node-role.kubernetes.io/master: ""
      containers:
        - command:
          -  /cloud-controller-manager
          - --leader-elect=true
          - --cloud-provider=alicloud
          - --use-service-account-credentials=true
          - --cloud-config=/etc/kubernetes/config/cloud-config.conf
          - --configure-cloud-routes=true
          - --route-reconciliation-period=3m
          - --leader-elect-resource-lock=endpoints
          # replace ${cluster-cidr} with your own cluster cidr
          # example: 172.16.0.0/16
          - --cluster-cidr=${ClusterCIDR}  # 此处需要依据系统实际情况进行替换
          # replace ${ImageVersion} with the latest release version
          # example: v2.1.0
          image: registry.cn-hangzhou.aliyuncs.com/acs/cloud-controller-manager-amd64:v2.1.0
          livenessProbe:
            failureThreshold: 8
            httpGet:
              host: 127.0.0.1
              path: /healthz
              port: 10258
              scheme: HTTP
            initialDelaySeconds: 15
            timeoutSeconds: 15
          name: cloud-controller-manager
          resources:
            requests:
              cpu: 200m
          volumeMounts:
            - mountPath: /etc/kubernetes/
              name: k8s
            - mountPath: /etc/ssl/certs
              name: certs
            - mountPath: /etc/pki
              name: pki
            - mountPath: /etc/kubernetes/config
              name: cloud-config
      hostNetwork: true
      volumes:
        - hostPath:
            path: /etc/kubernetes
          name: k8s
        - hostPath:
            path: /etc/ssl/certs
          name: certs
        - hostPath:
            path: /etc/pki
          name: pki
        - configMap:
            defaultMode: 420
            items:
              - key: cloud-config.conf
                path: cloud-config.conf
            name: cloud-config
          name: cloud-config

d. 部署CCM

kubectl create -f ccm.yaml
5. 结果验证

a. ccm-test.yaml

apiVersion: v1
kind: Service
metadata:
  name: nginx
  namespace: default
  annotations:
    service.beta.kubernetes.io/alibaba-cloud-loadbalancer-address-type: "intranet"
spec:
  ports:
  - port: 80
    protocol: TCP
    targetPort: 80
  selector:
    app: nginx
  type: LoadBalancer
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: test-nginx
spec:
  replicas: 2
  selector:
    matchLabels:
      app: nginx
  template:
    metadata:
      labels:
        app: nginx
    spec:
      containers:
      - name: nginx
        image: registry-vpc.cn-beijing.aliyuncs.com/eci_open/nginx:1.14.2

b. 部署Service和Deployment

kubectl create -f ccm-test.yaml

c. 联通性验证

kubectl get svc -A
kubectl get pod -A | grep nginx
6. 注意事项

配置参考: https://help.aliyun.com/zh/ack/ack-managed-and-ack-dedicated/user-guide/considerations-for-configuring-a-loadbalancer-type-service-1?spm=a2c4g.11186623.0.0.364c6abdi7hff7

备注: 指定系统内非 master 节点作为负载均衡节点,否则无法分配的公网 IP 无法正常访问。

总结

部署参考: https://help.aliyun.com/zh/eci/user-guide/deploy-the-ccm?spm=a2c4g.11186623.0.0.76e99ecckUzlfT

答疑参考: https://help.aliyun.com/zh/ack/ack-managed-and-ack-dedicated/user-guide/considerations-for-configuring-a-loadbalancer-type-service-1?spm=a2c4g.11186623.0.0.364c6abdi7hff7

悦读

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