查干湖
2024-12-04
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k8s（kubernetes）安装部署实例


k8s（kubernetes）安装部署实例

准备环境

  • Ubuntu版本：18.04
  • Docker: 20+
  • k8s: 1.21.3

两台主机，一台master，一台slave：

  • ubuntu01-master 192.168.2.123
  • ubuntu02-slave 192.168.2.124

注意：至少2CPU+2G内存配置

---------------------------------------------以下操作master和slave节点都要执行------------------------------------

安装Docker（20.版本）

apt-get update
apt install docker.io

系统初始化设置

#关闭防火墙
ufw disable

#关闭seLinux
sudo apt install selinux-utils
setenforce 0

#禁用swap分区
swapoff -a

#注释掉swap那一行
sudo vim /etc/fstab  

#桥接的IPV4流量传递到iptables的链
cat > /etc/sysctl.d/k8s.conf <<EOF
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
EOF
#生效
sysctl --system

配置k8s资源

apt install curl

curl -s https://mirrors.aliyun.com/kubernetes/apt/doc/apt-key.gpg | sudo apt-key add -

echo "deb https://mirrors.aliyun.com/kubernetes/apt/ kubernetes-xenial main" > /etc/apt/sources.list.d/kubernetes.list

apt-get update

安装nfs

apt-get install nfs-common

安装kubeadm(初始化cluster)，kubelet(启动pod)和kubectl(k8s命令工具)

apt install -y kubelet=1.21.3-00 kubeadm=1.21.3-00 kubectl=1.21.3-00

设置开机启动并启动kubelet

systemctl enable kubelet 
systemctl start kubelet

---------------------------------------------以上操作主从节点都要执行------------------------------------

-------------------------------------------------以下是主节点master操作-------------------------------------------

所需镜像文件如下列表，也可以提前docker pull下来：

-------------k8s组件镜像------------
kube-apiserver:v1.21.3
kube-controller-manager:v1.21.3
kube-scheduler:v1.21.3
kube-proxy:v1.21.3
pause:3.2
etcd:3.4.13-0
coredns:v1.8.0

---------------flannel 网络插件所需镜像，后面安装需要--------
flannel-cni-plugin:v1.2.0
flannel:v0.23.0

新建k8s.sh脚本，批量拉取镜像

vim k8s.sh

内容如下：

#!/bin/bash
images=(
 kube-apiserver:v1.21.3
 kube-controller-manager:v1.21.3
 kube-scheduler:v1.21.3
 kube-proxy:v1.21.3
 pause:3.2
 etcd:3.4.13-0
)
for imageName in ${images[@]} ; do
  docker pull registry.cn-hangzhou.aliyuncs.com/google_containers/${imageName}
  docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/${imageName} k8s.gcr.io/${imageName}
  docker rmi registry.cn-hangzhou.aliyuncs.com/google_containers/${imageName}
done
docker pull registry.cn-hangzhou.aliyuncs.com/google_containers/coredns:1.8.0
docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/coredns:1.8.0 registry.aliyuncs.com/google_containers/coredns:v1.8.0
docker rmi registry.cn-hangzhou.aliyuncs.com/google_containers/coredns:1.8.0

#给k8s.sh添加执行权限
chmod +x k8s.sh

#执行k8s.sh
./k8s.sh

初始化master

kubeadm init --image-repository=registry.aliyuncs.com/google_containers  --pod-network-cidr=10.244.0.0/16	 --service-cidr=10.96.0.0/12

初始化完成后如下图，出现successfully! 说明安装成功。

QQ截图20230926140153

记住以上成功后打印出来的两点信息：

第一，创建文件命令,(在master上运行一下)

#执行打印出来的信息
mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config

第二，节点加入命令（此命令ubuntu02-slave上执行）

join的信息是在ubuntu02-slave上执行一下命令即可加入到master中

#该命令在slave节点上执行
kubeadm join 192.168.2.123:6443 --token mqgb74.87li3ca2w48y21lw \
>         --discovery-token-ca-cert-hash sha256:7d4159e6dc60fb50b27bdbc58225a7cc51aedadc10ba2125108e9577d67ebc29
  • 若没有记录，也可在master节点用以下操作获取：kubeadm token create --print-join-command

安装网络插件flannel

拉取镜像flannel所需镜像文件（所有节点都需要）：

1.用docker pull 拉取镜像文件，或者网上下载
	flannel-cni-plugin:v1.2.0
	flannel:v0.23.0

2.将镜像打包成tar
    docker save -o flannel-cni-plugin_v1.2.0.tar flannel/flannel-cni-plugin:v1.2.0
    docker save -o flannel_v0.23.0.tar flannel/flannel:v0.23.0
3.将tar镜像压缩包，导入到containerd的k8s.io命名空间中，这样，下面的kube-flannel.yml文件中可以直接引用镜像地址了，要不然出现Init:ErrImagePull。
	sudo ctr -n k8s.io images import flannel-cni-plugin_v1.2.0.tar
	sudo ctr -n k8s.io images import flannel_v0.23.0.tar
4.验证是否导入成功，并记下路径，修改到kube-flannel.yml文件中。
	sudo ctr -n k8s.io i check | grep flannel

image-20241204163116576

下载kube-flannel.yml文件，并修改其中IP配置信息和上面初始化master时配置保持一致和本地镜像文件路径：

wget http://www.chenguanghu.com:88/k8s/kube-flannel.yml

  • 如果报错，浏览器打开网站复制到新建本地文本kube-flannel.yml，执行sudo kubectl apply -f kube-flannel.yml

  • 一下内容是kube-flannel.yml，注意里面IP配置信息和上面初始化master时配置保持一致

    ---
kind: Namespace
apiVersion: v1
metadata:
  name: kube-flannel
  labels:
    k8s-app: flannel
    pod-security.kubernetes.io/enforce: privileged
---
kind: ClusterRole
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  labels:
    k8s-app: flannel
  name: flannel
rules:
- apiGroups:
  - ""
  resources:
  - pods
  verbs:
  - get
- apiGroups:
  - ""
  resources:
  - nodes
  verbs:
  - get
  - list
  - watch
- apiGroups:
  - ""
  resources:
  - nodes/status
  verbs:
  - patch
- apiGroups:
  - networking.k8s.io
  resources:
  - clustercidrs
  verbs:
  - list
  - watch
---
kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  labels:
    k8s-app: flannel
  name: flannel
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: flannel
subjects:
- kind: ServiceAccount
  name: flannel
  namespace: kube-flannel
---
apiVersion: v1
kind: ServiceAccount
metadata:
  labels:
    k8s-app: flannel
  name: flannel
  namespace: kube-flannel
---
kind: ConfigMap
apiVersion: v1
metadata:
  name: kube-flannel-cfg
  namespace: kube-flannel
  labels:
    tier: node
    k8s-app: flannel
    app: flannel
data:
  cni-conf.json: |
    {
      "name": "cbr0",
      "cniVersion": "0.3.1",
      "plugins": [
        {
          "type": "flannel",
          "delegate": {
            "hairpinMode": true,
            "isDefaultGateway": true
          }
        },
        {
          "type": "portmap",
          "capabilities": {
            "portMappings": true
          }
        }
      ]
    }
  net-conf.json: |
    {
      "Network": "10.244.0.0/16",
      "Backend": {
        "Type": "vxlan"
      }
    }
---
apiVersion: apps/v1
kind: DaemonSet
metadata:
  name: kube-flannel-ds
  namespace: kube-flannel
  labels:
    tier: node
    app: flannel
    k8s-app: flannel
spec:
  selector:
    matchLabels:
      app: flannel
  template:
    metadata:
      labels:
        tier: node
        app: flannel
    spec:
      affinity:
        nodeAffinity:
          requiredDuringSchedulingIgnoredDuringExecution:
            nodeSelectorTerms:
            - matchExpressions:
              - key: kubernetes.io/os
                operator: In
                values:
                - linux
      hostNetwork: true
      priorityClassName: system-node-critical
      tolerations:
      - operator: Exists
        effect: NoSchedule
      serviceAccountName: flannel
      initContainers:
      - name: install-cni-plugin
        image: docker.io/flannel/flannel-cni-plugin:v1.2.0
        command:
        - cp
        args:
        - -f
        - /flannel
        - /opt/cni/bin/flannel
        volumeMounts:
        - name: cni-plugin
          mountPath: /opt/cni/bin
      - name: install-cni
        image: docker.io/flannel/flannel:v0.23.0
        command:
        - cp
        args:
        - -f
        - /etc/kube-flannel/cni-conf.json
        - /etc/cni/net.d/10-flannel.conflist
        volumeMounts:
        - name: cni
          mountPath: /etc/cni/net.d
        - name: flannel-cfg
          mountPath: /etc/kube-flannel/
      containers:
      - name: kube-flannel
        image: docker.io/flannel/flannel:v0.23.0
        command:
        - /opt/bin/flanneld
        args:
        - --ip-masq
        - --kube-subnet-mgr
        resources:
          requests:
            cpu: "100m"
            memory: "50Mi"
        securityContext:
          privileged: false
          capabilities:
            add: ["NET_ADMIN", "NET_RAW"]
        env:
        - name: POD_NAME
          valueFrom:
            fieldRef:
              fieldPath: metadata.name
        - name: POD_NAMESPACE
          valueFrom:
            fieldRef:
              fieldPath: metadata.namespace
        - name: EVENT_QUEUE_DEPTH
          value: "5000"
        volumeMounts:
        - name: run
          mountPath: /run/flannel
        - name: flannel-cfg
          mountPath: /etc/kube-flannel/
        - name: xtables-lock
          mountPath: /run/xtables.lock
      volumes:
      - name: run
        hostPath:
          path: /run/flannel
      - name: cni-plugin
        hostPath:
          path: /opt/cni/bin
      - name: cni
        hostPath:
          path: /etc/cni/net.d
      - name: flannel-cfg
        configMap:
          name: kube-flannel-cfg
      - name: xtables-lock
        hostPath:
          path: /run/xtables.lock
          type: FileOrCreate

    保存后执行：

    #添加执行权限
chmod +x kube-flannel.yml
sudo kubectl apply -f kube-flannel.yml

    查询组件状态

    kubectl get cs

    解决组件状态Unhealthy

    # 需要用#注释掉/etc/kubernetes/manifests下的kube-controller-manager.yaml和kube-scheduler.yaml的- – port=0
#注释掉 - - port=0 这一行 
cd /etc/kubernetes/manifests
vim kube-controller-manager.yaml
vim kube-scheduler.yaml

    注释完后重启服务

    systemctl restart kubelet

    再次查看组件状态（需要稍等）

    kubectl get cs

查看节点状态

kubectl get node

查看pod状态

kubectl get pods -A  （kubectl get pod -n kube-system -o wide ）

如果状态不对，请查看对应日志找错，比如：
kubectl -n kube-flannel logs kube-flannel-ds-58zkh
 ：-n代表namespace，logs后面是pod名

  • 若flannel没起来则查看其日志：
kubectl -n kube-system logs kube-flannel-ds-g59k5

kubectl describe node ubuntu02｜grep cider

QQ截图20230926141214

--------------------------------------------------以下是从节点slave操作-----------------------------------------------------

加入master,

如果忘记token可重新创建一个，kubeadm token create --print-join-command

#该命令在slave节点上执行
kubeadm join 192.168.2.123:6443 --token mqgb74.87li3ca2w48y21lw \
>         --discovery-token-ca-cert-hash sha256:7d4159e6dc60fb50b27bdbc58225a7cc51aedadc10ba2125108e9577d67ebc29
  • 如果忘记此命令，也可在master节点用以下操作获取：kubeadm token create --print-join-command

如下图：

QQ截图20230926140458

成功后，在master上可以查看益加入的slave节点

kubectl get node

image-20230926145712163

------------------------------------------以上至此部署完成----------------------------------

卸载k8s

  1. 清除集群所有资源：
kubectl delete --all all --all-namespaces
  1. 停止 Kubernetes 服务：
sudo systemctl stop kubelet
sudo systemctl stop docker
  1. 删除 Kubernetes 包：
sudo apt-get purge kubeadm kubectl kubelet kubernetes-cni
  1. 删除 Kubernetes 配置文件和目录：
sudo rm -rf /etc/kubernetes/
sudo rm -rf /var/lib/etcd/
sudo rm -rf ~/.kube/
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