前提条件：

1. 安装dockers
2. 下载sealos
3. 下载k8s离线包（v1.14.1,v1.15.0,v1.16.0,v1.17.0）14版本的下载链接找不到了，找到再补。
   启动docker

添加master节点
环境：

[root@node131 ~]# kubectl get node 
NAME        STATUS   ROLES    AGE    VERSION
cm-server   Ready    <none>   123d   v1.14.1
node130     Ready    master   135d   v1.14.1
node132     Ready    master   135d   v1.14.1

现在要往集群中添加node131为master。
在node130上操作

[root@node130 ~]# kubeadm init phase upload-certs --experimental-upload-certs
I0313 20:23:00.559871   28333 version.go:248] remote version is much newer: v1.17.4; falling back to: stable-1.14
[upload-certs] Storing the certificates in ConfigMap "kubeadm-certs" in the "kube-system" Namespace
[upload-certs] Using certificate key:
a4786889248af30b616aa8307968e56007b9be1821fefe922e040f6e5e85f5f4
[root@node130 ~]# kubeadm token create --print-join-command
kubeadm join apiserver.cluster.local:6443 --token 53e01r.qgkiaw0u5x72cuu1     --discovery-token-ca-cert-hash sha256:9e3e902497b8ab6c4e9111482aaed5a094013e00ff3f0d68f5489078480df3cf

把以上获得的两条进行拼接获得下面的join命令：

kubeadm join apiserver.cluster.local:6443 --token 53e01r.qgkiaw0u5x72cuu1     --discovery-token-ca-cert-hash sha256:9e3e902497b8ab6c4e9111482aaed5a094013e00ff3f0d68f5489078480df3cf \
--experimental-control-plane --certificate-key a4786889248af30b616aa8307968e56007b9be1821fefe922e040f6e5e85f5f4

在node131上操作：

tar zxvf kube1.14.1.tar.gz
cd kube/shell && sh init.sh

再执行join命令：

kubeadm join apiserver.cluster.local:6443 --token 53e01r.qgkiaw0u5x72cuu1     --discovery-token-ca-cert-hash sha256:9e3e902497b8ab6c4e9111482aaed5a094013e00ff3f0d68f5489078480df3cf \
--experimental-control-plane --certificate-key a4786889248af30b616aa8307968e56007b9be1821fefe922e040f6e5e85f5f4

遇到报错：error execution phase check-etcd: etcd cluster is not healthy: context deadline exceeded。
这个报错是因为etcd集群没有找到。
处理报错：
1、在kubeadm-config删除的状态不存在的etcd节点：
因为节点node131的etcd没有找到，所以我们在这里把它删除。

[root@node131 ~]# kubectl edit configmaps -n kube-system kubeadm-config

# Please edit the object below. Lines beginning with a '#' will be ignored,
# and an empty file will abort the edit. If an error occurs while saving this file will be
# reopened with the relevant failures.
#
apiVersion: v1
data:
  ClusterConfiguration: |
    apiServer:
      certSANs:
      - 127.0.0.1
      - apiserver.cluster.local
      - 192.168.3.130
      - 192.168.3.131
      - 192.168.3.132
      - 10.103.97.2
      extraArgs:
        authorization-mode: Node,RBAC
      timeoutForControlPlane: 4m0s
    apiVersion: kubeadm.k8s.io/v1beta1
    certificatesDir: /etc/kubernetes/pki
    clusterName: kubernetes
    controlPlaneEndpoint: apiserver.cluster.local:6443
    controllerManager: {}
    dns:
      type: CoreDNS
    etcd:
      local:
        dataDir: /var/lib/etcd
    imageRepository: k8s.gcr.io
    kind: ClusterConfiguration
    kubernetesVersion: v1.14.1
    networking:
      dnsDomain: cluster.local
      podSubnet: 100.64.0.0/10
      serviceSubnet: 10.96.0.0/12
    scheduler: {}
  ClusterStatus: |
    apiEndpoints:
      node130:
        advertiseAddress: 192.168.3.130
        bindPort: 6443
#      node131:
#        advertiseAddress: 192.168.3.131
#        bindPort: 6443
      node132:
        advertiseAddress: 192.168.3.132
        bindPort: 6443
    apiVersion: kubeadm.k8s.io/v1beta1
    kind: ClusterStatus
kind: ConfigMap
metadata:
  creationTimestamp: "2019-10-30T02:53:33Z"
  name: kubeadm-config
  namespace: kube-system
  resourceVersion: "775"
  selfLink: /api/v1/namespaces/kube-system/configmaps/kubeadm-config
  uid: 7640fad9-fac0-11e9-9990-e0d55e7a4876

因为etcd集群未自动删除此节点上的etcd成员，因此需要手动删除。
接下来还要进入etcd容器中把node131的配置删除。

[root@node132 kubernetes]# kubectl exec -it etcd-node130 sh -n kube-system 
/ # export ETCDCTL_API=3
/ #
/ # alias etcdctl='etcdctl --endpoints=https://192.168.3.130:2379 --cacert=/etc/kubernetes/pki/etcd/ca.crt --cert=/etc/kubernetes/pki/etcd/server.crt --key=/etc/kubernetes/pki/etcd/server.key'
/ #
/ # etcdctl member list 
ca953a0d64b48849, started, node132, https://192.168.3.132:2380, https://192.168.3.132:2379
df8b283813118626, started, node130, https://192.168.3.130:2380, https://192.168.3.130:2379
ea4c8cb8cc15f00b, started, node131, https://192.168.3.131:2380, https://192.168.3.131:2379
/ # etcdctl member remove ea4c8cb8cc15f00b
Member ea4c8cb8cc15f00b removed from cluster 884edae04b421411
/ # 
/ # etcdctl member list 
ca953a0d64b48849, started, node132, https://192.168.3.132:2380, https://192.168.3.132:2379
df8b283813118626, started, node130, https://192.168.3.130:2380, https://192.168.3.130:2379

最后每次kubeadm join失败后要kubeadm reset重置节点，在kubeadm join才会成功。

[root@node131 ~]# kubeadm reset
[root@node131 ~]# kubeadm join apiserver.cluster.local:6443 --token 53e01r.qgkiaw0u5x72cuu1     --discovery-token-ca-cert-hash sha256:9e3e902497b8ab6c4e9111482aaed5a094013e00ff3f0d68f5489078480df3cf \
--experimental-control-plane --certificate-key a4786889248af30b616aa8307968e56007b9be1821fefe922e040f6e5e85f5f4
[root@node131 ~]# mkdir -p $HOME/.kube
[root@node131 ~]# cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
[root@node131 ~]# chown $(id -u):$(id -g) $HOME/.kube/config

下面我们查看一下集群情况：

[root@node131 ~]# kubectl get nodes
NAME        STATUS   ROLES    AGE    VERSION
cm-server   Ready    <none>   123d   v1.14.1
node130     Ready    master   135d   v1.14.1
node131     Ready    master   52s    v1.14.1
node132     Ready    master   135d   v1.14.1

node131已经作为master加入到集群中了。

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