Master 端

使用kubeadm初始化，命令如下

kubeadm init \
--kubernetes-version=v1.15.1 \
--pod-network-cidr=10.244.0.0/16 \
--image-repository=\
registry.aliyuncs.com/google_containers

如果之前初始化过，可以使用 kubeadm reset 命令重置

上述命令输出大致如下,请记录输出内容，下一步加入node节点时会用到

[init] Using Kubernetes version: v1.15.1
[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 "etcd/ca" certificate and key
[certs] Generating "etcd/server" certificate and key
[certs] etcd/server serving cert is signed for DNS names [k8s-master localhost] and IPs [192.168.64.182 127.0.0.1 ::1]
[certs] Generating "etcd/healthcheck-client" certificate and key
[certs] Generating "apiserver-etcd-client" certificate and key
[certs] Generating "etcd/peer" certificate and key
[certs] etcd/peer serving cert is signed for DNS names [k8s-master localhost] and IPs [192.168.64.182 127.0.0.1 ::1]
[certs] Generating "front-proxy-ca" certificate and key
[certs] Generating "front-proxy-client" certificate and key
[certs] Generating "ca" certificate and key
[certs] Generating "apiserver-kubelet-client" certificate and key
[certs] Generating "apiserver" certificate and key
[certs] apiserver serving cert is signed for DNS names [k8s-master kubernetes kubernetes.default kubernetes.default.svc kubernetes.default.svc.cluster.local] and IPs [10.96.0.1 192.168.64.182]
[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 28.505452 seconds
[upload-config] Storing the configuration used in ConfigMap "kubeadm-config" in the "kube-system" Namespace
[kubelet] Creating a ConfigMap "kubelet-config-1.15" in namespace kube-system with the configuration for the kubelets in the cluster
[upload-certs] Skipping phase. Please see --upload-certs
[mark-control-plane] Marking the node k8s-master as control-plane by adding the label "node-role.kubernetes.io/master=''"
[mark-control-plane] Marking the node k8s-master as control-plane by adding the taints [node-role.kubernetes.io/master:NoSchedule]
[bootstrap-token] Using token: kn5x0g.2t2rd7todf2gvxkn
[bootstrap-token] Configuring bootstrap tokens, cluster-info ConfigMap, RBAC Roles
[bootstrap-token] configured RBAC rules to allow Node Bootstrap tokens to post CSRs in order for nodes to get long term certificate credentials
[bootstrap-token] configured RBAC rules to allow the csrapprover controller automatically approve CSRs from a Node Bootstrap Token
[bootstrap-token] configured RBAC rules to allow certificate rotation for all node client certificates in the cluster
[bootstrap-token] Creating the "cluster-info" ConfigMap in the "kube-public" namespace
[addons] Applied essential addon: CoreDNS
[addons] Applied essential addon: kube-proxy

Your Kubernetes control-plane 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/

Then you can join any number of worker nodes by running the following on each as root:

kubeadm join 192.168.64.182:6443 --token kn5x0g.2t2rd7todf2gvxkn \
    --discovery-token-ca-cert-hash sha256:4eb7556d8fefbbff36b76e7deabad38756b61fa31f243f6dbc3947e379f533b1

如果 kubectl工作在非root用户下，我们执行如下命令（这是上述输出的一部分）

mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config

如果 kubectl工作在root用户下，可以直接运行如下命令

export KUBECONFIG=/etc/kubernetes/admin.conf

查看所有的pod

kubectl get pods --all-namespaces

输出的内容大致如下

NAMESPACE     NAME                                 READY   STATUS    RESTARTS   AGE
kube-system   coredns-bccdc95cf-5hghj              0/1     Pending   0          95m
kube-system   coredns-bccdc95cf-lwph7              0/1     Pending   0          95m
kube-system   etcd-k8s-master                      1/1     Running   0          95m
kube-system   kube-apiserver-k8s-master            1/1     Running   0          95m
kube-system   kube-controller-manager-k8s-master   1/1     Running   0          95m
kube-system   kube-proxy-dhgmt                     1/1     Running   0          95m
kube-system   kube-proxy-sl65d                     1/1     Running   0          17m
kube-system   kube-scheduler-k8s-master            1/1     Running   0          94m

安装网络

kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/v0.10.0/Documentation/kube-flannel.yml

网络安装成功后，再次查看所有的pod

kubectl get pods --all-namespaces

这次输出的内容大致如下

NAMESPACE     NAME                                 READY   STATUS    RESTARTS   AGE
kube-system   coredns-bccdc95cf-5hghj              0/1     Running   0          95m
kube-system   coredns-bccdc95cf-lwph7              0/1     Running   0          95m
kube-system   etcd-k8s-master                      1/1     Running   0          95m
kube-system   kube-apiserver-k8s-master            1/1     Running   0          95m
kube-system   kube-controller-manager-k8s-master   1/1     Running   0          95m
kube-system   kube-proxy-dhgmt                     1/1     Running   0          95m
kube-system   kube-proxy-sl65d                     1/1     Running   0          17m
kube-system   kube-scheduler-k8s-master            1/1     Running   0          94m

Node

在每个Node所在的服务器上，运行如下命令，命令的内容，来自master所在服务器运行 kubeadm init 的输出

kubeadm join 192.168.64.182:6443 \
--token kn5x0g.2t2rd7todf2gvxkn \
--discovery-token-ca-cert-hash \
sha256:4eb7556d8fefbbff36b76e7deabad38756b61fa31f243f6dbc3947e379f533b1

回到 master 所在的服务器，运行 kubectl get nodes 可以看到全部node节点

本文参考 https://kubernetes.io/docs/setup/production-environment/tools/kubeadm/create-cluster-kubeadm