系统与版本
Centos7，Docker 20.10.9，kubernates 1.23.0
安装kubeadm
按照[官方的指引](https://kubernetes.io/zh/docs/setup/production-environment/tools/kubeadm/ )，我们选用`kubeadm`进行集群部署.
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硬件条件
内存2G，CPU2核
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关闭
firewall,iptables具体可以查看网上方法
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允许 iptables 检查桥接流量
cat <<EOF | sudo tee /etc/modules-load.d/k8s.conf br_netfilter EOF cat <<EOF | sudo tee /etc/sysctl.d/k8s.conf net.bridge.bridge-nf-call-ip6tables = 1 net.bridge.bridge-nf-call-iptables = 1 EOF sudo sysctl --system -
关闭
swap# 临时关闭，重启以后会重新开启 swapoff -a # 检查是否关闭 free -m # 如下关闭成功 [root@localhost ~]# free -m total used free shared buff/cache available Mem: 1819 260 1268 9 290 1406 Swap: 0 0 0vi /etc/fstab # # /etc/fstab # Created by anaconda on Wed Sep 1 15:01:27 2021 # # Accessible filesystems, by reference, are maintained under '/dev/disk' # See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info # UUID=e95686df-e97a-409f-968e-df388b13a239 / xfs defaults 0 0 UUID=3f5292fa-ab79-4e86-b036-27be00d2d84e /boot xfs defaults 0 0 # 注释掉swap #UUID=e2fd5a6a-0422-43b4-b3d3-c57c50c89b84 swap swap defaults 0 0 # 保存 wq # 重启主机 # 检查是否关闭 free -m # 如下固化关闭成功 [root@localhost ~]# free -m total used free shared buff/cache available Mem: 1819 260 1268 9 290 1406 Swap: 0 0 0 -
安装
kubeadmcat <<EOF | sudo tee /etc/yum.repos.d/kubernetes.repo [kubernetes] name=Kubernetes # 注意该处我们使用阿里云的镜像源 #baseurl=https://packages.cloud.google.com/yum/repos/kubernetes-el7-\$basearch baseurl=https://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-\$basearch enabled=1 gpgcheck=1 repo_gpgcheck=1 #gpgkey=https://packages.cloud.google.com/yum/doc/yum-key.gpg https://packages.cloud.google.com/yum/doc/rpm-package-key.gpg gpgkey=https://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg https://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg exclude=kubelet kubeadm kubectl EOF # 将 SELinux 设置为 permissive 模式（相当于将其禁用） sudo setenforce 0 sudo sed -i 's/^SELINUX=enforcing$/SELINUX=permissive/' /etc/selinux/config sudo yum install -y kubelet kubeadm kubectl --disableexcludes=kubernetes sudo systemctl enable --now kubelet -
配置host(选做，如果不做，以后的操作使用IP操作)
$ vi /etc/hosts 192.168.234.129 k8s-master 192.168.234.130 k8s-node1 192.168.234.131 k8s-node2 #保存 $ wq -
初始化k8s集群
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集群资源分配
角色 IP master 192.168.234.129 node1 192.168.234.130 node2 192.168.234.131 -
确认各主机中
kubelet处于正常运行（选做，kubeadm init初始化失败时排错 ）$ systemctl status kubelet # 查看状态，如果没开启就要开启 ● kubelet.service - kubelet: The Kubernetes Node Agent Loaded: loaded (/usr/lib/systemd/system/kubelet.service; enabled; vendor preset: disabled) Drop-In: /usr/lib/systemd/system/kubelet.service.d └─10-kubeadm.conf Active: active (running) since 六 2021-12-11 14:30:05 CST; 2s ago Docs: https://kubernetes.io/docs/ Main PID: 10469 (kubelet) Tasks: 11 Memory: 26.3M CGroup: /system.slice/kubelet.service └─10469 /usr/bin/kubeletkubelet不是启动状态，使用
journalctl -xeu kubelet命令检查启动失败原因-
kubelet cgroup driver: "systemd" is different from docker cgroup
上述原因是由于kubelet cgroup driver与docker cgroup driver不匹配，可以修改docker的cgroup driver与k8s的一致。
编辑
/etc/docker/daemon.json，加入以下配置{ ... "exec-opts": ["native.cgroupdriver=systemd"] ... }# 刷新配置 systemctl daemon-reload # 重启docker systemctl restart docker # 重启kubelet systemctl restart kubelet
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在master节点运行
# 注意，其中--image-repository指定初始化下载的镜像，--v=6开启详细日志打印 $ kubeadm init \ --image-repository=registry.aliyuncs.com/google_containers \ --apiserver-advertise-address=192.168.234.129 \ --kubernetes-version v1.23.0 \ --service-cidr=192.166.0.0/16 \ --pod-network-cidr=192.167.0.0/16 \ --v=6 # --image-repository镜像加速 # --apiserver-advertise-address 直接使用当前master主机地址 # --kubernetes-version k8s版本，可以不指定，缺省情况会用最新的 # --service-cidr k8s中的service网络地址，不可与主机，pod网络地址重复 # --pod-network-cidr pod网络地址，不可与主机，service网络地址重读，与后面的Calico相关 # --v,日志等级，5级以上会打印更详细的日志，方便差错#以下输出表示初始化完成 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 192.168.234.129:6443 --token pptc23.2kyz3xmu5ehv4j3p \ --discovery-token-ca-cert-hash sha256:fe9b576d3a52502ef46d09010cfc14cb6dfc4fdb885873ebf09cf8be7950f5b3 -
配置
kubectlmkdir -p $HOME/.kube sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config sudo chown $(id -u):$(id -g) $HOME/.kube/config -
安装Calico(CNI)
# 直接使用Calico远程配置文件，也可将文件上传至服务器安装 $ curl https://docs.projectcalico.org/manifests/calico.yaml -O $ kubectl apply -f calico.yaml -
node节点加入集群$ kubeadm join 192.168.234.129:6443 --token pptc23.2kyz3xmu5ehv4j3p \ --discovery-token-ca-cert-hash sha256:fe9b576d3a52502ef46d09010cfc14cb6dfc4fdb885873ebf09cf8be7950f5b3# 表示加入成功 [preflight] Running pre-flight checks [preflight] Reading configuration from the cluster... [preflight] FYI: You can look at this config file with 'kubectl -n kube-system get cm kubeadm-config -o yaml' [kubelet-start] Writing kubelet configuration to file "/var/lib/kubelet/config.yaml" [kubelet-start] Writing kubelet environment file with flags to file "/var/lib/kubelet/kubeadm-flags.env" [kubelet-start] Starting the kubelet [kubelet-start] Waiting for the kubelet to perform the TLS Bootstrap... This node has joined the cluster: * Certificate signing request was sent to apiserver and a response was received. * The Kubelet was informed of the new secure connection details. Run 'kubectl get nodes' on the control-plane to see this node join the cluster. -
配置节点角色
$ kubectl get nodes NAME STATUS ROLES AGE VERSION k8s-master Ready control-plane,master 23m v1.23.0 k8s-node1 Ready <none> 9m43s v1.23.0 k8s-node2 Ready <none> 7m41s v1.23.0 # 发现节点ROLES是<none> $ kubectl label nodes k8s-node1 node-role.kubernetes.io/node= $ kubectl label nodes k8s-node2 node-role.kubernetes.io/node= # 再次运行 $ kubectl get nodes NAME STATUS ROLES AGE VERSION k8s-master Ready control-plane,master 25m v1.23.0 k8s-node1 Ready node 12m v1.23.0 k8s-node2 Ready node 10m v1.23.0
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验证集群是否正常
apiVersion: apps/v1 kind: Deployment metadata: name: app-demo labels: app: app-demo spec: replicas: 3 template: metadata: name: app-demo labels: app: nginx-demo spec: containers: - name: nginx-demo image: nginx:stable-alpine imagePullPolicy: IfNotPresent ports: - containerPort: 80 restartPolicy: Always selector: matchLabels: app: nginx-demo --- apiVersion: v1 kind: Service metadata: name: nginx-svr spec: selector: app: nginx-demo ports: - protocol: TCP port: 10080 targetPort: 80 nodePort: 30080 type: NodePort --- apiVersion: v1 kind: Namespace metadata: name: ns-nginx labels: name: ns-nginx$ kubectl apply -f . $ kubectl get pods -o wide # 已经被分别部署到两个节点上，也能看到pod IP段是正常的 NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES app-demo-6ffbbc8f85-96fwg 1/1 Running 0 2m44s 192.167.36.65 k8s-node1 <none> <none> app-demo-6ffbbc8f85-pw4fw 1/1 Running 0 2m44s 192.167.169.130 k8s-node2 <none> <none> app-demo-6ffbbc8f85-rc2pb 1/1 Running 0 2m44s 192.167.169.129 k8s-node2 <none> <none>浏览器分别访问三台主机，均可出现nginx表示集群部署成功
