deb https://mirrors.aliyun.com/kubernetes/apt/ kubernetes-xenial main
2 apt-get update && apt-get install kubeadm

 apiVersion: kubeadm.k8s.io/v1alpha2

 kind: MasterConfiguration

 controllerManagerExtraArgs:

   horizontal-pod-autoscaler-use-rest-clients: "true"

   horizontal-pod-autoscaler-sync-period: "10s"

   node-monitor-grace-period: "10s"

 apiServerExtraArgs:

   runtime-config: "api/all=true"

 kubernetesVersion: "stable-1.12.2"

 kubeadm init --config kubeadm.yaml

 [ERROR Swap]: running with swap on is not supported. Please disable swap

 [ERROR SystemVerification]: missing cgroups: memory

 [ERROR ImagePull]: failed to pull image [k8s.gcr.io/kube-apiserver-amd64:v1.12.2]

. 报错很直白, 禁用swap分区即可. 
不过不建议使用： swapoff -a

从操作记录来看, 使用swapoff -a后kubeadm init命令虽然可以执行，但是却总是失败, 提示:

    [kubelet-check] It seems like the kubelet isn't running or healthy.

    [kubelet-check] The HTTP call equal to 'curl -sSL http://localhost:10248/healthz' failed with error: Get http://localhost:10248/healthz: dial tcp [::1]:10248: connect: connection refused.

查看日志发现实际还是swap没有关闭的问题：

➜  kubernetes  journalctl -xefu kubelet

11月  :: debian kubelet[]: F1105 ::28.609272     server.go:] failed to run Kubelet: Running with swap on is not supported, please disable swap! or set --fail-swap-on flag to false. /proc/swaps contained: [Filename                                Type                Size        Used        Priority /dev/sda9                               partition                        -]

➜  kubernetes  cat /proc/swaps

Filename                Type        Size    Used    Priority

/dev/sda9                               partition            -

➜  kubernetes  

注释掉/etc/fstab下swap挂载后安装成功



. echo GRUB_CMDLINE_LINUX=\"cgroup_enable=memory\" >> /etc/default/grub  && update-grub && reboot

. 国内正常网络不能从k8s.grc.io拉取镜像, 所以从docker.io拉取, 然后重新打上一个符合k8s的tag:

docker pull mirrorgooglecontainers/kube-apiserver:v1.12.2

docker pull mirrorgooglecontainers/kube-controller-manager:v1.12.2

docker pull mirrorgooglecontainers/kube-scheduler:v1.12.2

docker pull mirrorgooglecontainers/kube-proxy:v1.12.2

docker pull mirrorgooglecontainers/pause:3.1

docker pull mirrorgooglecontainers/etcd:3.2.

docker pull coredns/coredns:1.2.

docker tag docker.io/mirrorgooglecontainers/kube-apiserver:v1.12.2 k8s.gcr.io/kube-apiserver:v1.12.2

docker tag docker.io/mirrorgooglecontainers/kube-controller-manager:v1.12.2 k8s.gcr.io/kube-controller-manager:v1.12.2

docker tag docker.io/mirrorgooglecontainers/kube-scheduler:v1.12.2 k8s.gcr.io/kube-scheduler:v1.12.2

docker tag docker.io/mirrorgooglecontainers/kube-proxy:v1.12.2 k8s.gcr.io/kube-proxy:v1.12.2

docker tag docker.io/mirrorgooglecontainers/pause:3.1 k8s.gcr.io/pause:3.1

docker tag docker.io/mirrorgooglecontainers/etcd:3.2. k8s.gcr.io/etcd:3.2.

docker tag docker.io/coredns/coredns:1.2. k8s.gcr.io/coredns:1.2.

docker rmi mirrorgooglecontainers/kube-apiserver:v1.12.2

docker rmi mirrorgooglecontainers/kube-controller-manager:v1.12.2

docker rmi mirrorgooglecontainers/kube-scheduler:v1.12.2

docker rmi mirrorgooglecontainers/kube-proxy:v1.12.2

docker rmi mirrorgooglecontainers/pause:3.1

docker rmi mirrorgooglecontainers/etcd:3.2.

docker rmi coredns/coredns:1.2.

也可以增加加速器(测试163后速度比直接访问更慢), 加入方法如下，然后重启docker服务：

➜  kubernetes  cat /etc/docker/daemon.json

{

    "registry-mirrors": ["http://hub-mirror.c.163.com"]

}

➜  kubernetes  

➜  kubernetes  kubeadm init --config kubeadm.yaml

I1205 23:08:15.852917    5188 version.go:93] could not fetch a Kubernetes version from the internet: unable to get URL "https://dl.k8s.io/release/stable-1.12.2.txt": Get https://dl.k8s.io/release/stable-1.12.2.txt: net/http: request canceled while waiting for connection (Client.Timeout exceeded while awaiting headers)

I1205 23:08:15.853144    5188 version.go:94] falling back to the local client version: v1.12.2

[init] using Kubernetes version: v1.12.2

[preflight] running pre-flight checks

[preflight/images] Pulling images required for setting up a Kubernetes cluster

[preflight/images] This might take a minute or two, depending on the speed of your internet connection

[preflight/images] You can also perform this action in beforehand using 'kubeadm config images pull'

[kubelet] Writing kubelet environment file with flags to file "/var/lib/kubelet/kubeadm-flags.env"

[kubelet] Writing kubelet configuration to file "/var/lib/kubelet/config.yaml"

[preflight] Activating the kubelet service

[certificates] Generated front-proxy-ca certificate and key.

[certificates] Generated front-proxy-client certificate and key.

[certificates] Generated etcd/ca certificate and key.

[certificates] Generated etcd/server certificate and key.

[certificates] etcd/server serving cert is signed for DNS names [debian localhost] and IPs [127.0.0.1 ::1]

[certificates] Generated etcd/peer certificate and key.

[certificates] etcd/peer serving cert is signed for DNS names [debian localhost] and IPs [192.168.2.118 127.0.0.1 ::1]

[certificates] Generated etcd/healthcheck-client certificate and key.

[certificates] Generated apiserver-etcd-client certificate and key.

[certificates] Generated ca certificate and key.

[certificates] Generated apiserver certificate and key.

[certificates] apiserver serving cert is signed for DNS names [debian kubernetes kubernetes.default kubernetes.default.svc kubernetes.default.svc.cluster.local] and IPs [10.96.0.1 192.168.2.118]

[certificates] Generated apiserver-kubelet-client certificate and key.

[certificates] valid certificates and keys now exist in "/etc/kubernetes/pki"

[certificates] Generated sa key and public key.

[kubeconfig] Wrote KubeConfig file to disk: "/etc/kubernetes/admin.conf"

[kubeconfig] Wrote KubeConfig file to disk: "/etc/kubernetes/kubelet.conf"

[kubeconfig] Wrote KubeConfig file to disk: "/etc/kubernetes/controller-manager.conf"

[kubeconfig] Wrote KubeConfig file to disk: "/etc/kubernetes/scheduler.conf"

[controlplane] wrote Static Pod manifest for component kube-apiserver to "/etc/kubernetes/manifests/kube-apiserver.yaml"

[controlplane] wrote Static Pod manifest for component kube-controller-manager to "/etc/kubernetes/manifests/kube-controller-manager.yaml"

[controlplane] wrote Static Pod manifest for component kube-scheduler to "/etc/kubernetes/manifests/kube-scheduler.yaml"

[etcd] Wrote Static Pod manifest for a local etcd instance to "/etc/kubernetes/manifests/etcd.yaml"

[init] waiting for the kubelet to boot up the control plane as Static Pods from directory "/etc/kubernetes/manifests"

[init] this might take a minute or longer if the control plane images have to be pulled

[apiclient] All control plane components are healthy after 48.078220 seconds

[uploadconfig] storing the configuration used in ConfigMap "kubeadm-config" in the "kube-system" Namespace

[kubelet] Creating a ConfigMap "kubelet-config-1.12" in namespace kube-system with the configuration for the kubelets in the cluster

[markmaster] Marking the node debian as master by adding the label "node-role.kubernetes.io/master=''"

[markmaster] Marking the node debian as master by adding the taints [node-role.kubernetes.io/master:NoSchedule]

[patchnode] Uploading the CRI Socket information "/var/run/dockershim.sock" to the Node API object "debian" as an annotation

[bootstraptoken] using token: x4p0vz.tdp1xxxx7uyerrrs

[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 192.168.2.118:6443 --token x4p0vz.tdp1xxxx7uyerrrs --discovery-token-ca-cert-hash sha256:64cb13f7f004fe8dd3e6d0e246950f4cbdfa65e2a84f8988c3070abf8183b3e9

➜  kubernetes   

➜  kubernetes  kubectl get nodes

The connection to the server localhost: was refused - did you specify the right host or port?

➜  kubernetes  echo "export KUBECONFIG=/etc/kubernetes/admin.conf" >> ~/.bashrc

➜  kubernetes  source ~/.bashrc

➜  kubernetes  kubectl get nodes

NAME     STATUS     ROLES    AGE   VERSION

debian   NotReady   master   21m   v1.12.2

➜  kubernetes 

➜  kubernetes  kubectl get pods -n kube-system

NAME                             READY   STATUS              RESTARTS   AGE

coredns-576cbf47c7-4vjhf         /     Pending                       25m

coredns-576cbf47c7-xzjk7         /     Pending                       25m

etcd-debian                      /     Running                       25m

kube-apiserver-debian            /     Running                       25m

kube-controller-manager-debian   /     Running                       25m

kube-proxy-5wb6k                 /     Running                       25m

kube-scheduler-debian            /     Running                       25m

weave-net-nj7bk                  /     ContainerCreating             21s

➜  kubernetes  kubectl get pods -n kube-system

NAME                             READY   STATUS             RESTARTS   AGE

coredns-576cbf47c7-4vjhf         /     CrashLoopBackOff             27m

coredns-576cbf47c7-xzjk7         /     CrashLoopBackOff             27m

etcd-debian                      /     Running                      27m

kube-apiserver-debian            /     Running                      27m

kube-controller-manager-debian   /     Running                      27m

kube-proxy-5wb6k                 /     Running                      27m

kube-scheduler-debian            /     Running                      27m

weave-net-nj7bk                  /     Running                      2m32s

➜  kubernetes  kubectl get pods -n kube-system

NAME                             READY   STATUS    RESTARTS   AGE

coredns-576cbf47c7-4vjhf         /     Running             27m

coredns-576cbf47c7-xzjk7         /     Running             27m

etcd-debian                      /     Running             27m

kube-apiserver-debian            /     Running             27m

kube-controller-manager-debian   /     Running             27m

kube-proxy-5wb6k                 /     Running             27m

kube-scheduler-debian            /     Running             27m

weave-net-nj7bk                  /     Running             2m42s

➜  kubernetes  

➜  kubernetes  kubectl get nodes

NAME     STATUS   ROLES    AGE   VERSION

debian   Ready    master   38m   v1.12.2

➜  kubernetes  

➜  kubernetes  kubectl describe node debian | grep Taints

Taints:             node-role.kubernetes.io/master:NoSchedule

➜  kubernetes  

 . Pod主动声明允许在这种节点上运行(通过在Pod的yaml文件中的spec部分，加入 tolerations 字段即可)。

 . 对于总共就几台机器的k8s测试机器来说，最好的选择就是删除Taint:

 　　➜  kubernetes  kubectl taint nodes --all node-role.kubernetes.io/master-

 　　node/debian untainted

 　　➜  kubernetes  kubectl describe node debian | grep Taints

 　　Taints:             <none>

 　　➜  kubernetes  

由于master上kubeadm/kubelet都是v1.12.2版本，worker节点执行默认apt-get install时默认装了v1.13版本，导致加入集群失败，需卸载重装匹配的版本：

root@debian-vm:~# kubeadm version

kubeadm version: &version.Info{Major:"1", Minor:"13", GitVersion:"v1.13.0", GitCommit:"ddf47ac13c1a9483ea035a79cd7c10005ff21a6d", GitTreeState:"clean", BuildDate:"2018-12-03T21:02:01Z", GoVersion:"go1.11.2", Compiler:"gc", Platform:"linux/amd64"}

root@debian-vm:~# root@debian-vm:~# kubelet --version

Kubernetes v1.13.0

root@debian-vm:~# apt-get --purge remove kubeadm kubelet

root@debian-vm:~# apt-cache policy kubeadm

kubeadm:

  已安装：  (无)

  候选软件包：1.13.0-00

  版本列表：

     1.13.0-00 0

        500 https://mirrors.aliyun.com/kubernetes/apt/ kubernetes-xenial/main amd64 Packages

     1.12.3-00 0

        500 https://mirrors.aliyun.com/kubernetes/apt/ kubernetes-xenial/main amd64 Packages

     1.12.2-00 0

        500 https://mirrors.aliyun.com/kubernetes/apt/ kubernetes-xenial/main amd64 Packages

root@debian-vm:~# apt-get install kubeadm=1.12.2-00 kubelet=1.12.2-00

root@debian-vm:~# kubeadm join 192.168.2.118: --token x4p0vz.tdp1xxxx7uyerrrs --discovery-token-ca-cert-hash sha256:64cb13f7f004fe8dd3e6d0e246950f4cbdfa65e2a84f8988c3070abf8183b3e9

[preflight] running pre-flight checks

[discovery] Trying to connect to API Server "192.168.2.118:6443"

[discovery] Created cluster-info discovery client, requesting info from "https://192.168.2.118:6443"

[discovery] Requesting info from "https://192.168.2.118:6443" again to validate TLS against the pinned public key

[discovery] Cluster info signature and contents are valid and TLS certificate validates against pinned roots, will use API Server "192.168.2.118:6443"

[discovery] Successfully established connection with API Server "192.168.2.118:6443"

[kubelet] Downloading configuration for the kubelet from the "kubelet-config-1.12" ConfigMap in the kube-system namespace

[kubelet] Writing kubelet configuration to file "/var/lib/kubelet/config.yaml"

[kubelet] Writing kubelet environment file with flags to file "/var/lib/kubelet/kubeadm-flags.env"

[preflight] Activating the kubelet service

[tlsbootstrap] Waiting for the kubelet to perform the TLS Bootstrap...

[patchnode] Uploading the CRI Socket information "/var/run/dockershim.sock" to the Node API object "debian-vm" as an annotation

This node has joined the cluster:

* Certificate signing request was sent to apiserver and a response was received.

* The Kubelet was informed of the new secure connection details.

Run 'kubectl get nodes' on the master to see this node join the cluster.

root@debian-vm:~# 

节点加入集群成功

https://github.com/kubernetes/kubernetes/issues/54914

https://github.com/kubernetes/kubeadm/issues/610

https://blog.csdn.net/acxlm/article/details/79069468