Kubeadm安装K8s集群

电玩女神 2023-10-14 18:52 88阅读 0赞

##### 一、硬件环境 #####

*  准备3台Linux服务器，此处用Vmware虚拟机。

<table> 
 <thead> 
  <tr> 
   <th>主机名</th> 
   <th>CPU</th> 
   <th>内存</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td>k8smaster</td> 
   <td>2核</td> 
   <td>4G</td> 
  </tr> 
  <tr> 
   <td>k8snode1</td> 
   <td>2核</td> 
   <td>4G</td> 
  </tr> 
  <tr> 
   <td>k8snode2</td> 
   <td>2核</td> 
   <td>4G</td> 
  </tr> 
 </tbody> 
</table>

##### 二、系统前置准备 #####

*  配置三台主机的hosts文件

cat << EOF > /etc/hosts
    192.168.240.130 k8smaster
    192.168.240.132 k8snode1
    192.168.240.133 k8snode2
    EOF

*  设置主机名

hostnamectl set-hostname k8smaster
    hostnamectl set-hostname k8snode1
    hostnamectl set-hostname k8snode2

*  关闭selinux、禁用swap分区

sed -i 's/enforcing/disabled/' /etc/selinux/config 
    setenforce 0
    
    swapoff -a
    sed -ri 's/.*swap.*/#&/' /etc/fstab

*  ipv4流量转发

cat > /etc/sysctl.d/k8s.conf << EOF
    net.bridge.bridge-nf-call-ip6tables = 1
    net.bridge.bridge-nf-call-iptables = 1
    net.ipv4.ip_forward = 1
    EOF
    
    #让配置文件生效
    modprobe br_netfilter
    sysctl -p /etc/sysctl.d/k8s.conf

*  关闭防火墙

systemctl disable firewalld && systemctl stop firewalld

*  同步三台服务器的时间

yum install ntpdate -y
    ntpdate time.windows.com

##### 三、环境安装 #####

###### Docker 安装 ######

*  Docker卸载

systemctl stop docker 
    yum remove -y docker-ce docker-ce-cli containerd.io
    rm -rf /var/lib/docker
    rm -rf /var/lib/containerd

*  Docker 安装

yum -y install gcc
    yum -y install gcc-c++
    yum install -y yum-utils
    yum-config-manager --add-repo http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo
    yum makecache fast
    yum -y install docker-ce docker-ce-cli containerd.io
    systemctl enable docker && systemctl start docker
    cat > /etc/docker/daemon.json << EOF
    {
    "registry-mirrors": ["https://b9pmyelo.mirror.aliyuncs.com"]
    }
    EOF
    systemctl restart docker

###### k8s安装 ######

1.  配置k8s安装镜像

cat <<EOF > kubernetes.repo
    [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
    mv kubernetes.repo /etc/yum.repos.d/

1.  安装kubeadm 、kubectl、kubelet

yum remove -y kubelet kubeadm kubectl && yum install -y kubelet-1.16.2 kubectl-1.16.2 kubeadm-1.16.2 --disableexcludes=kubernetes

1.  设置kubelet开机自启动

systemctl enable kubelet

###### master节点配置 ######

1.  创建一个k8s的工作目录，生成一个kubeadm配置文件

mkdir k8s-install && cd k8s-install
    kubeadm config print init-defaults > kubeadm.yaml

1.  修改配置文件

#修改生成好的配置文件镜像与版本
    apiVersion: kubeadm.k8s.io/v1beta2
    bootstrapTokens:
    - groups:
      - system:bootstrappers:kubeadm:default-node-token
      token: abcdef.0123456789abcdef
      ttl: 24h0m0s
      usages:
      - signing
      - authentication
    kind: InitConfiguration
    localAPIEndpoint:
      advertiseAddress: 192.169.240.130
      bindPort: 6443
    nodeRegistration:
      criSocket: /var/run/dockershim.sock
      name: k8smaster
      taints:
      - effect: NoSchedule
        key: node-role.kubernetes.io/master
    ---
    apiServer:
      timeoutForControlPlane: 4m0s
    apiVersion: kubeadm.k8s.io/v1beta2
    certificatesDir: /etc/kubernetes/pki
    clusterName: kubernetes
    controllerManager: {
        }
    dns:
      type: CoreDNS
    etcd:
      local:
        dataDir: /var/lib/etcd
    imageRepository: registry.aliyuncs.com/google_containers #修改镜像源
    kind: ClusterConfiguration
    kubernetesVersion: v1.16.2 #修改版本
    networking:
      dnsDomain: cluster.local
      podSubnet: 10.244.0.0/16 #pod网络
      serviceSubnet: 10.96.0.0/12
    scheduler: {
        }

1.  下载kubeadm所需要的镜像

kubeadm config images pull --config kubeadm.yaml

![在这里插入图片描述][3f1c220f62c14f74a7f872ba33e8bc4d.png]

使用docker images 可查看下载的镜像信息  
![在这里插入图片描述][94193a41c02b498baa5d7057c6d87b66.png]

1.  使用kubeadm 初始化master节点

kubeadm init --config kubeadm.yaml

提示以下信息则表示初始化成功

![在这里插入图片描述][23563782454a44bd82612d6d64134a4c.png]

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
    
    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 192.168.240.130:6443 --token abcdef.0123456789abcdef \
        --discovery-token-ca-cert-hash sha256:1877573f37b7fd0bc9d8e38cf8d68f17f51e64a55606f7b657f3cdba79469f16

1.  按照提示创建目录

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

查看集群节点状态

kubectl get nodes

此时只有master节点是NotReady状态

1.  将两台node节点 加入到master节点中去（kubeadm join 是在master节点上初始化配置时生成的）

kubeadm join 192.168.240.130:6443 --token abcdef.0123456789abcdef \
        --discovery-token-ca-cert-hash sha256:1877573f37b7fd0bc9d8e38cf8d68f17f51e64a55606f7b657f3cdba79469f16

再次查看master节点信息

![在这里插入图片描述][732b9c0a167d46d0bc9dd6222a3062f3.png]

1.  安装flannel网络插件

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

编辑kube-flannel.yml

改成虚拟机的网卡名称

![在这里插入图片描述][f2c36920901b4c82824f2e82b378a2f8.png]

1.  下载flannel镜像

docker pull quay.io/coreos/flannel:v0.11.0-amd64
    kubectl create -f kube-flannel.yml

1.  查看集群节点状态

kubectl get pods -A

![在这里插入图片描述][077b739a0b2240319fe385ca0b6e2708.png]

*  master节点的组件

1.  api-server: api-server是主节点对外开发api的组件，同时提供restful方式,也可以用kubectl方式。
2.  etcd： 数据存储组件，api-server会将收到的指令存储到etcd中。
3.  sched ：负责接收指令，然后选举合适的node节点，通知节点进行容器的启停、负载均衡等。
4.  cm ：主节点控制中心，controller-manager。

*  node节点的组件

1.  kubelet : 用于管理节点中的容器启停，挂载等等。
2.  kube-proxy ： 用于节点间的网络通信、流量转发等。
3.  pod : pod是k8s中的最小调度单位，一个pod中可以包含至少1个容器。多个容器组成了一个pod。

[3f1c220f62c14f74a7f872ba33e8bc4d.png]: https://img-blog.csdnimg.cn/3f1c220f62c14f74a7f872ba33e8bc4d.png
[94193a41c02b498baa5d7057c6d87b66.png]: https://img-blog.csdnimg.cn/94193a41c02b498baa5d7057c6d87b66.png
[23563782454a44bd82612d6d64134a4c.png]: https://img-blog.csdnimg.cn/23563782454a44bd82612d6d64134a4c.png
[732b9c0a167d46d0bc9dd6222a3062f3.png]: https://img-blog.csdnimg.cn/732b9c0a167d46d0bc9dd6222a3062f3.png
[f2c36920901b4c82824f2e82b378a2f8.png]: https://img-blog.csdnimg.cn/f2c36920901b4c82824f2e82b378a2f8.png
[077b739a0b2240319fe385ca0b6e2708.png]: https://img-blog.csdnimg.cn/077b739a0b2240319fe385ca0b6e2708.png