您的位置:首页 > 运维架构 > Kubernetes

10分钟快速搭建Kubernetes容器集群平台

2018-10-09 09:14 1011 查看

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

    学习本专栏您能收获什么?

    • 掌握Docker、Kubernetes核心概念
    • 熟悉Docker日常运维管理
    • 熟练部署Kubernetes集群
    • 熟悉容器云平台日常运维管理
    • 容器云平台架构设计及规划
    • 将微服务业务架构迁移到容器云平台
    内容来自用户分享和网络整理,不保证内容的准确性,如有侵权内容,可联系管理员处理 点击这里给我发消息
    标签:  kubernetes k8s docker