10分钟搭建Kubernetes容器集群平台（kubeadm）

官方提供Kubernetes部署3种方式

minikube

Minikube是一个工具，可以在本地快速运行一个单点的Kubernetes，尝试Kubernetes或日常开发的用户使用。不能用于生产环境。

官方文档：https://kubernetes.io/docs/setup/minikube/

kubeadm

kubeadm可帮助你快速部署一套kubernetes集群。kubeadm设计目的为新用户开始尝试kubernetes提供一种简单的方法。目前是Beta版。

官方文档：https://kubernetes.io/docs/reference/setup-tools/kubeadm/kubeadm/
https://kubernetes.io/docs/setup/independent/install-kubeadm/

二进制包

从官方下载发行版的二进制包，手动部署每个组件，组成Kubernetes集群。目前企业生产环境中主要使用该方式。
下载地址：

1. 安装要求

内存2GB + ，2核CPU +

集群节点之间可以通信

每个节点唯一主机名，MAC地址和product_uuid

检查MAC地址：使用ip link或者ifconfig -a

检查product_uuid：cat /sys/class/dmi/id/product_uuid

禁止swap分区。这样才能使kubelet正常工作

2. 准备环境 关闭防火墙： # systemctl stop firewalld # systemctl disable firewalld 关闭selinux： # sed -i 's/enforcing/disabled/' /etc/selinux/config # setenforce 0 关闭swap： # swapoff -a # 临时 # vim /etc/fstab # 永久 添加主机名与IP对应关系： # cat /etc/hosts 192.168.0.11 k8s-master 192.168.0.12 k8s-node1 192.168.0.13 k8s-node2 同步时间： # yum install ntpdate -y # ntpdate ntp.api.bz 3. 安装Docker

Docker与Kubernetes关系图：

# yum install -y yum-utils device-mapper-persistent-data lvm2 # yum-config-manager --add-repo https://download.docker.com/linux/centos/docker-ce.repo # yum install docker-ce-17.03.3.ce -y #目前kubeadm最大支持docker-ce-17.03，所以要指定该版本安装 # systemctl enable docker && systemctl start docker

如果提示container-selinux依赖问题，先安装ce-17.03匹配版本：
# yum localinstall https://download.docker.com/linux/centos/7/x86_64/stable/Packages/docker-ce-selinux-17.03.3.ce-1.el7.noarch.rpm

4. 安装kubeadm，kubelet和kubectl

kubeadm： 引导集群的命令

kubelet：集群中运行任务的代理程序

kubectl：命令行管理工具

4.1 添加阿里云YUM软件源 # cat << EOF > /etc/yum.repos.d/kubernetes.repo [kubernetes] name=Kubernetes baseurl=https://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64 enabled=1 gpgcheck=1 repo_gpgcheck=1 gpgkey=https://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg https://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg EOF 4.2 安装kubeadm，kubelet和kubectl # yum install -y kubelet kubeadm kubectl --disableexcludes=kubernetes # systemctl enable kubelet && systemctl start kubelet

注意：使用Docker时，kubeadm会自动检查kubelet的cgroup驱动程序，并/var/lib/kubelet/kubeadm-flags.env在运行时将其设置在文件中。如果使用的其他CRI，则必须在/etc/default/kubelet中cgroup-driver值修改为cgroupfs：

# cat /var/lib/kubelet/kubeadm-flags.env KUBELET_KUBEADM_ARGS=--cgroup-driver=cgroupfs --cni-bin-dir=/opt/cni/bin --cni-conf-dir=/etc/cni/net.d --network-plugin=cni # systemctl daemon-reload # systemctl restart kubelet 5. 使用kubeadm创建单个Master集群 5.1 默认下载镜像地址在国外无法访问，先从准备好所需镜像

保存到脚本之间运行：

K8S_VERSION=v1.11.2 ETCD_VERSION=3.2.18 DASHBOARD_VERSION=v1.8.3 FLANNEL_VERSION=v0.10.0-amd64 DNS_VERSION=1.1.3 PAUSE_VERSION=3.1 # 基本组件 docker pull registry.cn-hangzhou.aliyuncs.com/google_containers/kube-apiserver-amd64:$K8S_VERSION docker pull registry.cn-hangzhou.aliyuncs.com/google_containers/kube-controller-manager-amd64:$K8S_VERSION docker pull registry.cn-hangzhou.aliyuncs.com/google_containers/kube-scheduler-amd64:$K8S_VERSION docker pull registry.cn-hangzhou.aliyuncs.com/google_containers/kube-proxy-amd64:$K8S_VERSION docker pull registry.cn-hangzhou.aliyuncs.com/google_containers/etcd-amd64:$ETCD_VERSION docker pull registry.cn-hangzhou.aliyuncs.com/google_containers/pause:$PAUSE_VERSION docker pull registry.cn-hangzhou.aliyuncs.com/google_containers/coredns:$DNS_VERSION # 网络组件 docker pull quay.io/coreos/flannel:$FLANNEL_VERSION # 修改tag docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/kube-apiserver-amd64:$K8S_VERSION k8s.gcr.io/kube-apiserver-amd64:$K8S_VERSION docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/kube-controller-manager-amd64:$K8S_VERSION k8s.gcr.io/kube-controller-manager-amd64:$K8S_VERSION docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/kube-scheduler-amd64:$K8S_VERSION k8s.gcr.io/kube-scheduler-amd64:$K8S_VERSION docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/kube-proxy-amd64:$K8S_VERSION k8s.gcr.io/kube-proxy-amd64:$K8S_VERSION docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/etcd-amd64:$ETCD_VERSION k8s.gcr.io/etcd-amd64:$ETCD_VERSION docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/pause:$PAUSE_VERSION k8s.gcr.io/pause:$PAUSE_VERSION docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/coredns:$DNS_VERSION k8s.gcr.io/coredns:$DNS_VERSION 5.2 初始化Master # kubeadm init --kubernetes-version=1.11.2 --pod-network-cidr=10.244.0.0/16 --apiserver-advertise-address=192.168.0.11 ... Your Kubernetes master has initialized successfully! To start using your cluster, you need to run (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 addon options listed at: You can now join any number of machines by running the following on each node as root: kubeadm join --token <token> <master-ip>:<master-port> --discovery-token-ca-cert-hash sha256:<hash> mkdir -p $HOME/.kube sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config sudo chown $(id -u):$(id -g) $HOME/.kube/config 5.3 安装Pod网络 - 插件 # kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/v0.10.0/Documentation/kube-flannel.yml 5.4 加入工作节点