1 修改主机名（所有主机）

规划三台机器，如下：

ip	主机名称	最低配置	职责
192.168.1.200	k8s-master	4核8G	master节点
192.168.1.201	k8s-node1	2核8G	node节点
192.168.1.202	k8s-node2	2核8G	node节点

hostnamectl set-hostname k8s-master
hostnamectl set-hostname k8s-node1
hostnamectl set-hostname k8s-node2

修改host文件（三台机器一致，可配置一台后，使用scp命名复制到其它机器）

cat >> /etc/hosts << EOF
192.168.1.200 k8s-master
192.168.1.201 k8s-node1
192.168.1.202 k8s-node2
EOF

scp命名复制到其它机器

scp /etc/hosts root@192.168.1.201:/etc/hosts
scp /etc/hosts root@192.168.1.202:/etc/hosts

2.配置阿里云官方源（所有主机）

mkdir -p /etc/yum.repos.d/back
find /etc/yum.repos.d/ -type f -exec mv {} /etc/yum.repos.d/back/ \;
curl -o /etc/yum.repos.d/CentOS-Base.repo https://mirrors.aliyun.com/repo/Centos-7.repo
sed -i -e '/mirrors.cloud.aliyuncs.com/d' -e '/mirrors.aliyuncs.com/d' /etc/yum.repos.d/CentOS-Base.repo

3.关闭防火墙（所有主机）

systemctl stop firewalld.service
systemctl disable firewalld.service

4.关闭交换分区和selinux（所有主机）

sed -i.bak '/swap/s/^/#/' /etc/fstab
sed -i 's/^ *SELINUX=enforcing/SELINUX=disabled/g' /etc/selinux/config

5.配置内核转发等相关参数（所有主机）

modprobe br_netfilter

cat <<EOF >  /etc/sysctl.d/k8s.conf
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
EOF

cat << EOF >> /etc/sysctl.conf
net.ipv4.ip_forward=1
EOF

chmod a+x /etc/rc.local
echo "source /etc/profile" >> /etc/rc.local
echo "modprobe br_netfilter" >> /etc/rc.local
echo "sysctl -p /etc/sysctl.d/k8s.conf" >> /etc/rc.local
echo "sysctl -p" >> //etc/rc.local

reboot  

6.安装containerd（所有主机）

由于新的Kubernates [1.24.0以上] 建议使用contanerd, 而且kubernates如何使用containerd 不会像使用docker一样，要中间转几层，故其性能很好。大概CPU使用率减少60%，内存使用率能减少12%。

wget https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo -O /etc/yum.repos.d/docker-ce.repo 

sudo yum install -y yum-utils device-mapper-persistent-data lvm2
sudo yum install -y containerd.io containerd

sudo systemctl stop containerd.service

sudo containerd config default > /etc/containerd/config.toml
sudo sed -i "s#registry.k8s.io/pause#registry.cn-hangzhou.aliyuncs.com/google_containers/pause#g" /etc/containerd/config.toml

# 更改/etc/containerd/config.toml  ，disabled_plugins 中删除 cri
vi /etc/containerd/config.toml
sudo sed -i "s#SystemdCgroup = false#SystemdCgroup = true#g" /etc/containerd/config.toml

sudo systemctl enable --now containerd.service
sudo systemctl status containerd.service

sudo modprobe br_netfilter

7.安装k8s（所有主机）

sudo yum install -y kubelet-1.28.0 kubeadm-1.28.0 kubectl-1.8.0 --disableexcludes=kubernetes --nogpgcheck
sudo systemctl daemon-reload
sudo systemctl restart kubelet
sudo systemctl enable kubelet

8.初始化k8s（master节点）

kubeadm init --kubernetes-version=1.28.0 --apiserver-advertise-address=192.168.1.200 --pod-network-cidr=10.244.0.0/16 --image-repository registry.aliyuncs.com/google_containers

对集群做config认证

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

Node节点加入集群

kubeadm join 192.168.1.200:6443 --token i2meul.73ipaykm3jc2k6vs --discovery-token-ca-cert-hash sha256:9e6d95ffc5ba78a5c71352ffcc9bca2330b17264ebc44facf6359b1ac153f33f

9安装flannel插件（CNI）

#创建文件夹
mkdir flannel && cd flannel
#下载文件
curl -O https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
# kube-flannel.yml里需要下载镜像,我这里提前先下载
docker pull quay.io/coreos/flannel:v0.14.0-rc1
#创建flannel网络插件
kubectl apply -f kube-flannel.yml

#过一会查看k8s集群节点,变成Ready状态了
kubectl get nodes
NAME         STATUS   ROLES    AGE     VERSION
k8s-master   Ready    master   9m39s   v1.19.3

在获取kube-flannel.yml文件时发现很慢，有时候还打不开，索性就记录一下吧，如果curl不到，也可以用下面的代码直接在本地vi一个kube-flannel.yml文件

---
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:v0.22.3
        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:v0.22.3
        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