鉴于使用二进制的方式安装较为复杂,且不太好处理证书的生成,分发等问题,并且对性能没有较高的要求,所以强烈推荐使用此模式,具体下来这个模式的好处为:

  • 官方提供的工具,有官方的文档支持
  • 安装贼简单,没有其他的依赖
  • 扩展性强,有官方的一些扩展支持
  • 集群全部以容器启动,所以没那么多你需要管理的service

准备

硬件

  1. 一台或多台运行 Ubuntu 16.04 + 的主机(其他linux系统也行)
  2. 集群中完整的网络连接，公网或者私网都可以

各节点环境

  • #### docker

使用加入器安装docker

  curl https://releases.rancher.com/install-docker/17.03.sh | sh
  • #### 禁用swap

然后需要禁用 swap 文件，这是 Kubernetes 的强制步骤。编辑/etc/fstab文件，注释掉引用swap的行，保存并重启后输入sudo swapoff -a即可

  vim /etc.fastab
  #注释调swap的行
  sudo swapoff -a

  • 设置源

    sudo apt-get update && sudo apt-get install -y apt-transport-https
curl -s https://gitee.com/tanx/kubernetes-test/raw/master/kubeadm/apt-key.gpg | sudo apt-key add -
  
sudo cat <<EOF >/etc/apt/sources.list.d/kubernetes.list
deb http://mirrors.ustc.edu.cn/kubernetes/apt/ kubernetes-xenial main
EOF

安装master

  1. 安装kubelet,kubeadm,kubectl

    sudo apt-get update
sudo apt-get install -y kubelet kubeadm kubectl

  2. 编辑 kubeadm 配置文件

    kubeadm-config.yaml

    apiVersion: kubeadm.k8s.io/v1beta1
kind: ClusterConfiguration
imageRepository: registry.cn-hangzhou.aliyuncs.com/google_containers
kubernetesVersion: v1.13.1
controlPlaneEndpoint: k8s-cluster.smile13.com:6443 #你的k8s的访问地址
apiServer:
  certSANs:
    - k8s-cluster.smile13.com       ##你的k8s的访问地址
networking:
  serviceSubnet: 10.96.0.0/12
  podSubnet: 192.168.0.0/16
  dnsDomain: "cluster.local"

    完整的可以参考 https://godoc.org/k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm/v1beta1

  3. 提前拉取镜像(可选)

    kubeadm config images pull --config kubeadm-config.yaml

  4. 初始化master1

    [root@k8s01 ~]# kubeadm init --config kubeadm-config.yaml
   
[init] Using Kubernetes version: v1.13.1
[preflight] Running pre-flight checks
[preflight] Pulling images required for setting up a Kubernetes cluster
[preflight] This might take a minute or two, depending on the speed of your internet connection
[preflight] You can also perform this action in beforehand using 'kubeadm config images pull'
[kubelet-start] Writing kubelet environment file with flags to file "/var/lib/kubelet/kubeadm-flags.env"
[kubelet-start] Writing kubelet configuration to file "/var/lib/kubelet/config.yaml"
[kubelet-start] Activating the kubelet service
[certs] Using certificateDir folder "/etc/kubernetes/pki"
[certs] Generating "ca" certificate and key
[certs] Generating "apiserver" certificate and key
[certs] apiserver serving cert is signed for DNS names [k8s01 kubernetes kubernetes.default kubernetes.default.svc kubernetes.default.svc.cluster.local k8s-cluster.smile13.com k8s-cluster.smile13.com] and IPs [10.96.0.1 192.168.158.131]
[certs] Generating "apiserver-kubelet-client" certificate and key
[certs] Generating "etcd/ca" certificate and key
[certs] Generating "etcd/server" certificate and key
[certs] etcd/server serving cert is signed for DNS names [k8s01 localhost] and IPs [192.168.158.131 127.0.0.1 ::1]
[certs] Generating "etcd/peer" certificate and key
[certs] etcd/peer serving cert is signed for DNS names [k8s01 localhost] and IPs [192.168.158.131 127.0.0.1 ::1]
[certs] Generating "etcd/healthcheck-client" certificate and key
[certs] Generating "apiserver-etcd-client" certificate and key
[certs] Generating "front-proxy-ca" certificate and key
[certs] Generating "front-proxy-client" certificate and key
[certs] Generating "sa" key and public key
[kubeconfig] Using kubeconfig folder "/etc/kubernetes"
[kubeconfig] Writing "admin.conf" kubeconfig file
[kubeconfig] Writing "kubelet.conf" kubeconfig file
[kubeconfig] Writing "controller-manager.conf" kubeconfig file
[kubeconfig] Writing "scheduler.conf" kubeconfig file
[control-plane] Using manifest folder "/etc/kubernetes/manifests"
[control-plane] Creating static Pod manifest for "kube-apiserver"
[control-plane] Creating static Pod manifest for "kube-controller-manager"
[control-plane] Creating static Pod manifest for "kube-scheduler"
[etcd] Creating static Pod manifest for local etcd in "/etc/kubernetes/manifests"
[wait-control-plane] Waiting for the kubelet to boot up the control plane as static Pods from directory "/etc/kubernetes/manifests". This can take up to 4m0s
[apiclient] All control plane components are healthy after 28.003045 seconds
[uploadconfig] storing the configuration used in ConfigMap "kubeadm-config" in the "kube-system" Namespace
[kubelet] Creating a ConfigMap "kubelet-config-1.13" in namespace kube-system with the configuration for the kubelets in the cluster
[patchnode] Uploading the CRI Socket information "/var/run/dockershim.sock" to the Node API object "k8s01" as an annotation
[mark-control-plane] Marking the node k8s01 as control-plane by adding the label "node-role.kubernetes.io/master=''"
[mark-control-plane] Marking the node k8s01 as control-plane by adding the taints [node-role.kubernetes.io/master:NoSchedule]
[bootstrap-token] Using token: t1yovr.ag1xbdhfgo36z8f7
[bootstrap-token] Configuring bootstrap tokens, cluster-info ConfigMap, RBAC Roles
[bootstraptoken] configured RBAC rules to allow Node Bootstrap tokens to post CSRs in order for nodes to get long term certificate credentials
[bootstraptoken] configured RBAC rules to allow the csrapprover controller automatically approve CSRs from a Node Bootstrap Token
[bootstraptoken] configured RBAC rules to allow certificate rotation for all node client certificates in the cluster
[bootstraptoken] creating the "cluster-info" ConfigMap in the "kube-public" namespace
[addons] Applied essential addon: CoreDNS
[addons] Applied essential addon: kube-proxy
   
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/config
   
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/
   
You can now join any number of machines by running the following on each node
as root:
   
 kubeadm join k8s-cluster.smile13.com:6443 --token t1yovr.ag1xbdhfgo36z8f7 --discovery-token-ca-cert-hash sha256:ceaf1b9a9ef558ff8706331cb88e81c28d48528972cee2b92a8416364768e45d
   
[root@k8s01 ~]# mkdir -p $HOME/.kube
[root@k8s01 ~]# cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
[root@k8s01 ~]# chown $(id -u):$(id -g) $HOME/.kube/config

  5. 查看集群状态

    [root@k8s01 ~]# kubectl get cs
NAME                 STATUS    MESSAGE              ERROR
controller-manager   Healthy   ok                   
scheduler            Healthy   ok                   
etcd-0               Healthy   {"health": "true"}   
[root@k8s01 ~]# kubectl get nodes
NAME    STATUS     ROLES    AGE     VERSION
k8s01   NotReady   master   4m45s   v1.13.1

  6. 安装网络插件

    kubectl apply -f https://docs.projectcalico.org/v3.3/getting-started/kubernetes/installation/hosted/rbac-kdd.yaml
    
kubectl apply -f https://docs.projectcalico.org/v3.3/getting-started/kubernetes/installation/hosted/kubernetes-datastore/calico-networking/1.7/calico.yaml

  7. 复制安装文件到其他master

    [root@k8s01 k8s-install]# cd /etc/kubernetes && tar cvzf k8s-key.tgz pki/ca.* pki/sa.* pki/front-proxy-ca.* pki/etcd/ca.* admin.conf
pki/ca.crt
pki/ca.key
pki/sa.key
pki/sa.pub
pki/front-proxy-ca.crt
pki/front-proxy-ca.key
pki/etcd/ca.crt
pki/etcd/ca.key
admin.conf
[root@k8s01 kubernetes]# scp /etc/kubernetes/k8s-key.tgz k8s02:/etc/kubernetes/
[root@k8s01 kubernetes]# scp /etc/kubernetes/k8s-key.tgz k8s03:/etc/kubernetes/
    
######到对应的master解压k8s-key.tgz包
    
######复制kubeadm-config.yaml到其他master（用于从阿里云下载镜像，也可以不复制，直接pull需要的镜像，这里我为了方便直接copy配置文件进行pull）
[root@k8s01 ~]# scp  k8s-install/kubeadm-config.yaml k8s02:~
kubeadm-config.yaml  
[root@k8s01 ~]# scp  k8s-install/kubeadm-config.yaml k8s03:~
kubeadm-config.yaml

原理

  1. 在进行更改之前，运行一系列飞行前检查以验证系统状态。

  2. 生成自签名CA（或使用现有CA），以便为群集中的每个组件设置标识。如果用户通过将其放入通过--cert-dir （/etc/kubernetes/pki默认情况下）配置的cert目录中提供了自己的CA证书和/或密钥，则会跳过此步骤。

  3. 将kubeconfig文件写入kubelet /etc/kubernetes/，控制器管理器和调度程序以用于连接到API服务器，每个API服务器都有自己的标识，以及另一个用于管理命名的kubeconfig文件admin.conf。

  4. 为API服务器，控制器管理器和调度程序生成静态Pod清单。如果未提供外部etcd，则会为etcd生成其他静态Pod清单。

安装其他master

拉取镜像

kubeadm config images pull --config kubeadm-config.yaml

初始化master

kubeadm join k8s-cluster.smile13.com:6443 --token t1yovr.ag1xbdhfgo36z8f7 --discovery-token-ca-cert-hash sha256:ceaf1b9a9ef558ff8706331cb88e81c28d48528972cee2b92a8416364768e45d --experimental-control-plane

一定注意此处加入了新的参数–experimental-control-plane

查看集群状态

[root@k8s01 ~]# kubectl get nodes
NAME    STATUS   ROLES    AGE     VERSION
k8s01   Ready    master   31m     v1.13.1
k8s02   Ready    master   4m51s   v1.13.1