部署k8s集群

环境配置

三台机器相同配置：

系统	CPU	内存	硬盘
Centos 7	2C	2G	20G

采用 kubeadm 部署

所有节点执行：

SH
# 1、关闭防火墙
systemctl stop firewalld
systemctl disable firewalld

# 2、关闭selinux
setenforce 0
sed -i 's/SELINUX=enforcing/SELINUX=disabled/' /etc/selinux/config

# 3、关闭swap（临时关闭）
swapoff -a

# 4、设置网桥参数
cat << EOF > /etc/sysctl.d/k8s.conf
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
net.ipv4.ip_forward = 1
EOF

# 5、修改主机名
hostnamectl set-hostname master  # 主节点
hostnamectl set-hostname node01  # node01节点
hostnamectl set-hostname node02  # node02节点

# 6、添加主机域名信息（三台机器执行）
cat >> /etc/hosts <<EOF
192.168.44.136 master
192.168.44.141 node01
192.168.44.142 node02
EOF

部署docker

docker版本	镜像源
26.1.3	阿里云

可根据需求自行下载对应docker版本

所有节点安装：

sh
# 1、安装依赖
yum install -y yum-utils device-mapper-persistent-data lvm2

# 2、配置阿里云 yum 源
yum-config-manager --add-repo https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo

# 3、下载docker
yum -y install docker-ce

# 4、创建 /etc/docker/ 目录
mkdir -p /etc/docker/
#设置国内阿里云docker源，地址改为自己在阿里云容器镜像服务申请的地址即可。
#设置cgroupdriver为systemd，这步尤为重要，如果不设置，后续k8s部署时会报错

tee /etc/docker/daemon.json <<-'EOF'
{
  "registry-mirrors": ["https://40d9jgnm.mirror.aliyuncs.com"],
  "exec-opts": ["native.cgroupdriver=systemd"]
}
EOF

# 5、重启docker
systemctl deamon-reload
systemctl restart docker
systemctl enable docker

# 检查环境
docker info

部署k8s

k8s版本	镜像源
1.27.6	阿里云

可根据需求自行下载对应k8s版本

配置yum源

所有节点执行

sh
cat <<EOF > /etc/yum.repos.d/kubernetes.repo
[kubernetes]
name=Kubernetes
baseurl=https://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64/
enabled=1
gpgcheck=1
repo_gpgcheck=1
gpgkey=https://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg https://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg
EOF

安装引导组件

kubelet ：运行在cluster，负责启动pod管理容器
kubeadm ：k8s快速构建工具，用于初始化cluster
kubectl ：k8s命令工具，部署和管理应用，维护组件

sh
# 主节点安装所有组件
yum install -y --nogpgcheck kubelet-1.27.6 kubeadm-1.27.6 kubectl-1.27.6

# 从节点安装 kubelet 和 kubeadm
yum install -y --nogpgcheck kubelet-1.27.6 kubeadm-1.27.6

启动kubelet

所有节点执行：


systemctl daemon-reload
systemctl start kubelet
systemctl enable kubelet

拉取初始化配置文件

init-config 主要由 api server、etcd、scheduler、controller-manager、coredns等镜像构成

master节点执行：

sh
kubeadm config print init-defaults > init-config.yaml

# 修改刚才拉取的 init-config.yaml 文件，一共三处修改
apiVersion: kubeadm.k8s.io/v1beta3
bootstrapTokens:
- groups:
  - system:bootstrappers:kubeadm:default-node-token
  token: abcdef.0123456789abcdef
  ttl: 24h0m0s
  usages:
  - signing
  - authentication
kind: InitConfiguration
localAPIEndpoint:
  advertiseAddress: 1.2.3.4   #修改1 本机ip地址
  bindPort: 6443
nodeRegistration:
  criSocket: /var/run/dockershim.sock
  imagePullPolicy: IfNotPresent
  name: master   #修改2 主机名
  taints: null
---
apiServer:
  timeoutForControlPlane: 4m0s
apiVersion: kubeadm.k8s.io/v1beta3
certificatesDir: /etc/kubernetes/pki
clusterName: kubernetes
controllerManager: {}
dns: {}
etcd:
  local:
    dataDir: /var/lib/etcd
imageRepository: registry.aliyuncs.com/google_containers   #修改3 修改为阿里云地址
kind: ClusterConfiguration
kubernetesVersion: 1.27.6
networking:
  dnsDomain: cluster.local
  serviceSubnet: 10.96.0.0/12
scheduler: {}

修改containerd

与我们之前配置docker镜像源的做法类似，在国内使用containerd依然需要更换成国内的镜像源

所有节点执行：

sh
containerd config default > /etc/containerd/config.toml
cat /etc/containerd/config.toml | grep -n "sandbox_image"

# 修改sandbox_image的值为 "registry.aliyuncs.com/google_containers/pause:3.6"
vim /etc/containerd/config.toml
sandbox_image = "registry.aliyuncs.com/google_containers/pause:3.9" （这里改一下）

# 重启 containerd 服务
systemctl daemon-reload
systemctl restart containerd

拉取k8s相关镜像

sh
kubeadm config images pull --config=init-config.yaml

如果拉取失败，可以通过命令列出需要的镜像后逐个拉取

sh
kubeadm config images list --config init-config.yaml

初始化master节点

将 192.168.44.136 替换为你自己的 master 节点

master节点执行：

sh
kubeadm init --apiserver-advertise-address=192.168.44.136 --apiserver-bind-port=6443 --pod-network-cidr=10.244.0.0/16  --service-cidr=10.96.0.0/12 --kubernetes-version=1.27.6 --image-repository registry.aliyuncs.com/google_containers --v=6

如果安装报错终止了

sh
# 重置集群
kubeadm reset

# 排错之后再重新执行 init（--v=6可帮助我们看更详细的报错）

初始master成功

初始完成后会提示执行三个命令

master节点执行：

sh
mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config

在下面有让node节点加入集群的命令

初始化node节点

将node加入集群的命令复制下来

在所有node节点执行：

sh
# 注意不要有换行标志，不让会报错
kubeadm join 192.168.44.136:6443 --token w34ha2.66if2c8nwmeat9o7 --discovery-token-ca-cert-hash sha256:20e2227554f8883811c01edd850f0cf2f396589d32b57b9984de3353a7389477

部署网络插件

Flannel是CoreOS团队针对Kubernetes设计的一个网络规划服务，简单来说，它的功能是让集群中的不同节点主机创建的Docker容器都具有全集群唯一的虚拟IP地址

sh
# 下载
wget https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml

# 应用
kubectl apply -f kube-flannel.yml

这时候可以看到多了三个pod

sh
kubectl get po -A

如果下载不下来，新建 yaml 手动复杂粘贴

yaml
---
kind: Namespace
apiVersion: v1
metadata:
  name: kube-flannel
  labels:
    pod-security.kubernetes.io/enforce: privileged
---
kind: ClusterRole
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: flannel
rules:
- apiGroups:
  - ""
  resources:
  - pods
  verbs:
  - get
- apiGroups:
  - ""
  resources:
  - nodes
  verbs:
  - list
  - watch
- apiGroups:
  - ""
  resources:
  - nodes/status
  verbs:
  - patch
---
kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  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:
  name: flannel
  namespace: kube-flannel
---
kind: ConfigMap
apiVersion: v1
metadata:
  name: kube-flannel-cfg
  namespace: kube-flannel
  labels:
    tier: node
    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
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: flannelcni/flannel-cni-plugin:v1.1.0 for ppc64le and mips64le (dockerhub limitations may apply)
        image: docker.io/rancher/mirrored-flannelcni-flannel-cni-plugin:v1.1.0
        command:
        - cp
        args:
        - -f
        - /flannel
        - /opt/cni/bin/flannel
        volumeMounts:
        - name: cni-plugin
          mountPath: /opt/cni/bin
      - name: install-cni
       #image: flannelcni/flannel:v0.20.0 for ppc64le and mips64le (dockerhub limitations may apply)
        image: docker.io/rancher/mirrored-flannelcni-flannel:v0.20.0
        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: flannelcni/flannel:v0.20.0 for ppc64le and mips64le (dockerhub limitations may apply)
        image: docker.io/rancher/mirrored-flannelcni-flannel:v0.20.0
        command:
        - /opt/bin/flanneld
        args:
        - --ip-masq
        - --kube-subnet-mgr
        resources:
          requests:
            cpu: "100m"
            memory: "50Mi"
          limits:
            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