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:https://github.com/kubernetes/kubernetes/blob/master/CHANGELOG-1.11.md#v1113

1. 安装要求

  • 操作系统

    • Ubuntu 16.04+
    • Debian 9
    • CentOS 7
    • RHEL 7
    • Fedora 25/26 (best-effort)
    • 其他
  • 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: http://kubernetes.io/docs/admin/addons/ 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

在Node节点切换到root账号执行:

# kubeadm join 192.168.0.11:6443 --token 6hk68y.0rdz1wdjyh85ntkr --discovery-token-ca-cert-hash sha256:d1d3f59ae37fbd632707cbeb9b095d0d0b19af535078091993c4bc4d9d2a7782 

格式:kubeadm join --token <token> <master-ip>:<master-port> --discovery-token-ca-cert-hash sha256:<hash>

6. kubernetes dashboard

先将yaml文件下载下来,修改里面镜像地址和Service NodePort类型。

# wget https://raw.githubusercontent.com/kubernetes/dashboard/master/src/deploy/recommended/kubernetes-dashboard.yaml 

修改镜像地址:

# registry.cn-hangzhou.aliyuncs.com/google_containers/kubernetes-dashboard-amd64:v1.10.0 

修改Service:

kind: Service apiVersion: v1 metadata: labels: k8s-app: kubernetes-dashboard name: kubernetes-dashboard namespace: kube-system spec: type: NodePort ports: - port: 443 targetPort: 8443 nodePort: 30001 selector: k8s-app: kubernetes-dashboard 
# kubectl apply -f kubernetes-dashboard.yaml 

创建一个管理员角色:

apiVersion: v1 kind: ServiceAccount metadata: name: dashboard-admin namespace: kube-system --- kind: ClusterRoleBinding apiVersion: rbac.authorization.k8s.io/v1beta1 metadata: name: dashboard-admin subjects: - kind: ServiceAccount name: dashboard-admin namespace: kube-system roleRef: kind: ClusterRole name: cluster-admin apiGroup: rbac.authorization.k8s.io 
# kubectl apply -f k8s-admin.yaml 

使用上述创建账号的token登录Kubernetes Dashboard:

# kubectl get secret -n kube-system # kubectl describe secret dashboard-admin-token-bwdjj -n kube-system ... token: eyJhbGciOiJSUzI1NiIsImtpZCI6IiJ9.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.0hQU5Di_P1OX1DcnW2AYzjDAED66EOrqhF5iupv39wvB8wE-aLRSQyp0twX2M8u1KMZ67n6LxbH17VwEQkMDRVXs7ZlUCyAAD6kHDz3k-f7PAzH5vcuyO4veQ9ooVjk3DKjrP4zXQChHllBB1wmD_oyLjoWxK3Z5MBTlVGzSixVwuQNpFPbuS6Z7iLGwUOgjI0cGZ9Tt6cXzcK81KfAEpDIP_CtFV_Jw4s98EgBex9mZh6vq1dcxr03qfuK--udd_8GWZctu_p_P15hZZLoKEm5GCbs6JGvKL2aao_DEHfLp3XYEnApojI91vU4qAqdkvMZ2qWQNGYv4KNi2yPOOJQ 

技术彩蛋

在2018/2019年Docker/Kubernetes容器技术无疑是业内最火的技术。根据招聘简介情况来看,容器技术已成为运维工程师、架构师必备技能。 为帮助大家快速掌握这门主流技术,少走弯路,提高核心竞争力。决定写《基于Kubernetes企业容器云平台落地与实践》文章专栏,给朋友在企业落地容器云平台提供一些企业实践性指导,希望自己所学所思的东西能够帮助到大家,能够有所启发。

传送门:基于Kubernetes企业容器云平台落地与实践

若你在容器运维中,遇到容器方面的问题,可以给我微信↓。同样,若发现文章有任何纰漏,还请随时指正,相互学习,共同进步!