# 加入集群

#### Master加入集群组成高可用 <a href="#wow36" id="wow36"></a>

**复制KEY到各个master节点**

**复制文件到 k8s-master-02**

```
ssh root@master02.k8s.io mkdir -p /etc/kubernetes/pki/etcd
scp /etc/kubernetes/admin.conf root@master02.k8s.io:/etc/kubernetes
scp /etc/kubernetes/pki/{ca.*,sa.*,front-proxy-ca.*} root@master02.k8s.io:/etc/kubernetes/pki
scp /etc/kubernetes/pki/etcd/ca.* root@master02.k8s.io:/etc/kubernetes/pki/etcd
```

**master节点加入集群**

```
kubeadm join master.k8s.io:16443 --token dm3cw1.kw4hq84ie1376hji --discovery-token-ca-cert-hash sha256:f079b624773145ba714b56e177f52143f90f75a1dcebabda6538a49e224d4009 --experimental-control-plane
......
This node has joined the cluster and a new control plane instance was created:

* Certificate signing request was sent to apiserver and approval was received.
* The Kubelet was informed of the new secure connection details.
* Master label and taint were applied to the new node.
* The Kubernetes control plane instances scaled up.
* A new etcd member was added to the local/stacked etcd cluster.

To start administering your cluster from this node, 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

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

> 如果加入失败，请输入 kubeadm reset 重置，重新执行从“复制KEY”和“加入集群”这两步

**配置kubectl环境变量**

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

#### node节点加入集群 <a href="#wow37" id="wow37"></a>

除了让master节点加入集群组成高可用外，slave节点也要加入集群中。

这里将k8s-node-01、k8s-node-02加入集群，进行工作

输入初始化k8s master时候提示的加入命令，如下：

```
kubeadm join master.k8s.io:16443 --token dm3cw1.kw4hq84ie1376hji --discovery-token-ca-cert-hash sha256:f079b624773145ba714b56e177f52143f90f75a1dcebabda6538a49e224d4009

```

#### 如果忘记加入集群的token和sha256 (如正常则跳过) <a href="#wow38" id="wow38"></a>

显示获取token列表

```
kubeadm token list
```

默认情况下 Token 过期是时间是24小时，如果 Token 过期以后，可以输入以下命令，生成新的 Token

```
kubeadm token create
```

获取ca证书sha256编码hash值

```
openssl x509 -pubkey -in /etc/kubernetes/pki/ca.crt | openssl rsa -pubin -outform der 2>/dev/null | openssl dgst -sha256 -hex | sed 's/^.* //'
```

拼接命令

```
kubeadm join master.k8s.io:16443 --token 882ik4.9ib2kb0eftvuhb58 --discovery-token-ca-cert-hash sha256:0b1a836894d930c8558b350feeac8210c85c9d35b6d91fde202b870f3244016a 
```

> 对于master加入，请加上 --experimental-control-plane 参数

#### 查看各个节点加入集群情况 <a href="#wow39" id="wow39"></a>

```
kubectl get nodes -o wide
NAME            STATUS   ROLES    AGE   VERSION   INTERNAL-IP    EXTERNAL-IP   OS-IMAGE                KERNEL-VERSION              CONTAINER-RUNTIME
k8s-master-01   Ready    master   12m   v1.13.10   192.168.1.101   <none>        CentOS Linux 7 (Core)   3.10.0-957.1.3.el7.x86_64   docker://18.6.3
k8s-master-02   Ready    master   10m   v1.13.10   192.168.1.102   <none>        CentOS Linux 7 (Core)   3.10.0-957.1.3.el7.x86_64   docker://18.6.3
k8s-node-01     Ready    <none>   68s   v1.13.10   192.168.1.103   <none>        CentOS Linux 7 (Core)   3.10.0-957.1.3.el7.x86_64   docker://18.6.3
k8s-node-02     Ready    <none>   61s   v1.13.10   192.168.1.104   <none>        CentOS Linux 7 (Core)   3.10.0-957.1.3.el7.x86_64   docker://18.6.3
```