序言本人在安裝 k8s 的過程中曲折不斷，故寫下此文，讓後人可以少走彎路。這篇文章只描述如何從0開始快速搭建 k8s 叢集，想更詳細瞭解具體遇到問題的分析過程和解決方案，可閱讀另一篇文章 —— CentOS7 使用 kubeadm 啟動 kubernetes 叢集（踩坑篇）本人在認知、語言、技術及閱歷等種種方面不足，如若文中有誤，煩請告知，必將一一更正，郵箱 [email protected]。建議學習 Kubernetes（簡稱K8s） 之前，需要有 Linux 基礎以及基本掌握 Docker 的使用，在天朝區域網環境下還額外需要科學上網技巧。 簡介Kubernetes (通常稱為K8s

) 是用於自動部署、擴充套件和管理容器化（containerized）應用程式的開源系統 —— 複製於維基百科。環境系統及核心版本CentOS Linux release 7.4.1708 (Core) 最小化安裝核心版本 3.10.0-693.el7.x86_64系統位數 x86_64Docker-CEClient: Version: 18.03.1-ce API version: 1.37 Go version: go1.9.5 Git commit: 9ee9f40 Built: Thu Apr 26 07:20:16 2018 OS/Arch: linux/amd64 Experimental: false Orchestrator: swarmServer: Engine: Version: 18.03.1-ce API version: 1.37 (minimum version 1.12) Go version: go1.9.5 Git commit: 9ee9f40 Built: Thu Apr 26 07:23:58 2018 OS/Arch: linux/amd64 Experimental: falsekubeadm

kubeadm version: &version.Info{Major:"1", Minor:"10", GitVersion:"v1.10.2", GitCommit:"81753b10df112992bf51bbc2c2f85208aad78335", GitTreeState:"clean", BuildDate:"2018-04-27T09:10:24Z", GoVersion:"go1.9.3", Compiler:"gc", Platform:"linux/amd64"}kubeletVersion: v1.10.2kubectlClient Version: version.Info{Major:"1", Minor:"10", GitVersion:"v1.10.2", GitCommit:"81753b10df112992bf51bbc2c2f85208aad78335", GitTreeState:"clean", BuildDate:"2018-04-27T09:22:21Z", GoVersion:"go1.9.3", Compiler:"gc", Platform:"linux/amd64"}Server Version: version.Info{Major:"1", Minor:"10", GitVersion:"v1.10.2", GitCommit:"81753b10df112992bf51bbc2c2f85208aad78335", GitTreeState:"clean", BuildDate:"2018-04-27T09:10:24Z", GoVersion:"go1.9.3", Compiler:"gc", Platform:"linux/amd64"}文件

KubernetesDocker安裝系統準備1. 更新系統軟體yum -y upgrade2.安裝常用軟體yum -y install vim3.設定翻牆代理此代理地址是我區域網的一臺機器，讀者可自行更換，NO_PROXY 的 IP 則是本機的 IPecho -e "export HTTP_PROXY=http://192.168.1.100:1080\nexport HTTPS_PROXY=http://192.168.1.100:1080\nexport NO_PROXY=192.168.19.150" >> /etc/profile4.禁用 swapsed -i "s/.*swap.*/# &/g" /etc/fstab5.開放所需埠firewall-cmd --zone=public --add-port=6443/tcp --permanent && firewall-cmd --zone=public --add-port=10250/tcp --permanent && firewall-cmd --reload6.重啟reboot安裝 Docker-CE1. 安裝依賴軟體yum install -y yum-utils device-mapper-persistent-data lvm22.設定 yum 源yum-config-manager \ --add-repo \ https://download.docker.com/linux/centos/docker-ce.repo3.禁用 edgeyum-config-manager --disable docker-ce-edge4.安裝最新穩定版本yum install -y docker-ce5.開機啟動 dockersystemctl enable docker && systemctl start docker6.配置代理mkdir -p /etc/systemd/system/docker.service.dtouch /etc/systemd/system/docker.service.d/http-proxy.confecho -e '[Service]\nEnvironment="HTTP_PROXY=http://192.168.1.100:1080"' > /etc/systemd/system/docker.service.d/http-proxy.conftouch /etc/systemd/system/docker.service.d/https-proxy.confecho -e '[Service]\nEnvironment="HTTPS_PROXY=http://192.168.1.100:1080"' > /etc/systemd/system/docker.service.d/https-proxy.confsystemctl daemon-reload && systemctl restart docker檢視 docker infodocker info | grep -i proxyHTTP Proxy: http://192.168.1.100:1080HTTPS Proxy: http://192.168.1.100:1080安裝 kubeadm，kubelet，kubectlkubeadm —— 啟動 k8s 叢集的命令工具kubelet —— 叢集容器內的命令工具kubectl —— 操作叢集的命令工具1.新增 kubernetes 的 yum 源cat <<EOF > /etc/yum.repos.d/kubernetes.repo[kubernetes]name=Kubernetesbaseurl=https://packages.cloud.google.com/yum/repos/kubernetes-el7-\$basearchenabled=1gpgcheck=1repo_gpgcheck=1gpgkey=https://packages.cloud.google.com/yum/doc/yum-key.gpg https://packages.cloud.google.com/yum/doc/rpm-package-key.gpgEOF2. 安裝 kubeadm，kubelet，kubectlyum install -y kubelet kubeadm kubectl開機啟動 kubeletsystemctl enable kubelet && systemctl start kubelet修改 kubeadm 配置，使 kubelet 與 docker 的 cgroup-driver 一致為 cgruopfssed -i "s/cgroup-driver=systemd/cgroup-driver=cgroupfs/g" /etc/systemd/system/kubelet.service.d/10-kubeadm.conf重啟 kubeletsystemctl daemon-reload && systemctl restart kubelet3. 初始化叢集kubeadm init --ignore-preflight-errors=all --pod-network-cidr=192.168.0.0/16 等待初始化 k8s 叢集成功Your Kubernetes master 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/configYou 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/You can now join any number of machines by running the following on each nodeas root: kubeadm join 192.168.19.150:6443 --token i2yq5b.tpmy284orbzssb5a --discovery-token-ca-cert-hash sha256:f598777ca9d1f5bb7eee7e30e13cb41934473be0ec8bce9c917795e07156ae04你還需要給叢集部署一個 pod 網路，讓 pod 內部服務之間可以相互通訊我使用了 Calico ，根據官方文件，它需要以 192.168.0.0/16 網段來初始化useradd k8smkdir -p /home/k8s/.kubecp -i /etc/kubernetes/admin.conf /home/k8s/.kube/configchown k8s:k8s /home/k8s/.kube/config切換到 k8s 使用者su -l k8s安裝 Calico pod network kubectl get nodesNAME STATUS ROLES AGE VERSIONbogon NotReady master 8m v1.10.2測試環境使用單機叢集，可以使用如下命令，讓 master 上也可以有 podkubectl taint nodes --all node-role.kubernetes.io/master-kubeadm join 加入叢集注意：如果忘記了 token 的 hash，可以在沒有 reset （k8s 相關容器沒有被刪除）的情況下再次執行 kubeadm init 獲得，日誌中的 token 是相同的使用 root 使用者執行:kubeadm join 192.168.19.150:6443 --token i2yq5b.tpmy284orbzssb5a --discovery-token-ca-cert-hash sha256:f598777ca9d1f5bb7eee7e30e13cb41934473be0ec8bce9c917795e07156ae04 --ignore-preflight-errors=all出現如下日誌，則加入叢集成功[discovery] Successfully established connection with API Server "192.168.19.150:6443"This node has joined the cluster:* Certificate signing request was sent to master and a response was received.* The Kubelet was informed of the new secure connection details.Run 'kubectl get nodes' on the master to see this node join the cluster.執行 kubectl get nodesNAME STATUS ROLES AGE VERSIONbogon Ready master 28m v1.10.2刪除節點首先釋放 bogon 節點資源kubectl drain bogon --delete-local-data --force --ignore-daemonsets刪除 bogon 節點kubectl delete node bogon檢視節點kubectl get nodesNo resources found.至此搭建 k8s 叢集就大功告成了！