K8S集群搭建1.28.x

1、Kubernetes集群规划

主机名	IP地址	说明
master	192.168.33.201	主节点
node1	192.168.33.202	从节点
noide2	192.168.33.202	从节点

2、准备环境

1、关闭防火墙

systemctl stop firewalld
systemctl disable firewalld

2、关闭selinux

sed -i 's/enforcing/disabled/' /etc/selinux/config

3、关闭swap分区

sed -ri 's/.*swap.*/#&/' /etc/fstab 

4、规划主机名

master节点

hostnamectl set-hostname master

node1节点

hostnamectl set-hostname node1

node2节点

hostnamectl set-hostname node2

5、添加hosts文件

在master节点添加

cat >> /etc/hosts << EOF
192.168.33.201 k8s-master
192.168.33.202 k8s-node1
192.168.33.205 k8s-node2
EOF

将hosts文件复制到其他节点

scp /etc/hosts node1:/etc/hosts
scp /etc/hosts node2:/etc/hosts

6、将桥接的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
sysctl --system

7、同步时间

yum install ntpdate -y
ntpdate time.windows.com

2、安装Docker

1、安装docker

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

2、设置docker开机自启

systemctl enable docker && systemctl start docker

3、配置daemon.json

$ cat > /etc/docker/daemon.json << EOF
{
  "registry-mirrors": ["https://b9pmyelo.mirror.aliyuncs.com"]
}
EOF

重启docker

systemctl restart docker

4、生成config.tom配置文件

containerd config default > /etc/containerd/config.toml

5、配置systemd cgroup驱动

sed -i 's/SystemdCgroup = false/SystemdCgroup = true/g' /etc/containerd/config.toml

将sandbox_image下载地址改为阿里云地址

# 在/etc/containerd/config.toml中设置

[plugins."io.containerd.grpc.v1.cri"]
    ...
    sandbox_image = "registry.aliyuncs.com/google_containers/pause:3.9"

启动containerd 并设置开机自启动

systemctl restart containerd && systemctl enable containerd

3、安装kubeadm,kublelet和kubectl

1、添加阿里云的yum软件源

cat > /etc/yum.repos.d/kubernetes.repo << EOF
[kubernetes]
name=Kubernetes
baseurl=https://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64
enabled=1
gpgcheck=0
repo_gpgcheck=0
gpgkey=https://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg https://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg
EOF

2、安装kubeadm,kublelet和kubectl

由于版本更新频繁，这里指定版本号部署：

yum install -y kubelet-1.28.2 kubeadm-1.28.2 kubectl-1.28.2
systemctl enable kubelet 

4、集群搭建

1、初始化

在Master节点执行

 kubeadm init \
  --apiserver-advertise-address=192.168.33.201\
  --image-repository registry.aliyuncs.com/google_containers \
  --kubernetes-version v1.28.2 \
  --service-cidr=10.96.0.0/12 \
  --pod-network-cidr=10.244.0.0/16

由于默认拉取镜像地址k8s.gcr.io国内无法访问，这里指定阿里云镜像仓库地址。

Your Kubernetes control-plane has initialized successfully!

To start using your cluster, you need to run the following as a regular user:

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

Alternatively, if you are the root user, you can run:

  export KUBECONFIG=/etc/kubernetes/admin.conf

You should now deploy a pod network to the cluster.
Run "kubectl apply -f [podnetwork].yaml" with one of the options listed at:
  https://kubernetes.io/docs/concepts/cluster-administration/addons/

Then you can join any number of worker nodes by running the following on each as root:

kubeadm join 192.168.33.201:6443 --token esce21.q6hetwm8si29qxwn \
    --discovery-token-ca-cert-hash sha256:00603a05805807501d7181c3d60b478788408cfe6cedefedb1f97569708be9c5

如果出现以上字段，则说明初始化成功

创建集训没有成功，重现初始化时需要进行一下操作：

kubeadm reset        # 环境及网络清理
rm -rf $HOME/.kube   # 重新创建集群时,需要删除 $HOME/.kube目录

使用kubectl工具

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

2、加入工作节点

在node1和node2执行

向集群添加新节点，执行在kubeadm init输出的kubeadm join命令：

kubeadm join 192.168.33.201:6443 --token esce21.q6hetwm8si29qxwn \
    --discovery-token-ca-cert-hash sha256:00603a05805807501d7181c3d60b478788408cfe6cedefedb1f97569708be9c5

默认token有效期为24小时，当过期之后，该token就不可用了。这时就需要重新创建token，操作如下：

kubeadm token create --print-join-command

3、查看

[root@master ~]# kubectl get node
NAME     STATUS   ROLES           AGE    VERSION
master   NotReady control-plane   118m   v1.28.2
node1    NotReady           80m    v1.28.2
node2    NotReady           80m    v1.28.2

搭建成功之后这里德STATUS处于NotReady的状态，我们需要给其部署网络插件

5、部署网络插件calico

kubectl apply -f calico.yaml

6、测试kubernetes集群

kubectl create deployment nginx --image=nginx
kubectl expose deployment nginx --port=80 --type=NodePort
kubectl get pod,svc

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