k8s集群加入一个新的node节点

实验目的：在已有的k8s集群中加入一个新的node节点，并正常工作。

已有的k8s集群节点信息：centos7.9 kubeadm 安装kubernetes集群
192.168.206.130 master
192.168.206.131 k8s-node1
192.168.206.136 k8s-node2
新加入一个节点：
192.168.206.138 k8s-node3

kubectl get nodes

 kubectl get nodes -o wide

 在进行下面的步骤之前，要找到最初创建k8s集群时，系统提示的用来将新节点加入集群的语句：

kubeadm join 192.168.206.130:6443 --token abcdef.0123456789abcdef --discovery-token-ca-cert-hash sha256:97a177b891f75f92f07e61aedbfc8a34cd35d6785d55b9cc829dcf532e1de5b9

找不到怎么办？在master上执行下面这句：

kubeadm token create --print-join-command

下面正式开始：

第一步：初始化系统参数 ，修改hosts和hostname

        1，,130,131,136，分别写入hosts：

echo "192.168.206.138 k8s-node3" >>/etc/hosts

        2，新节点138如下：

#修改hosts和hostname
echo "192.168.206.130 master" >>/etc/hosts
echo "192.168.206.131 k8s-node1" >>/etc/hosts
echo "192.168.206.136 k8s-node2" >>/etc/hosts
echo "192.168.206.138 k8s-node3" >>/etc/hosts
hostname k8s-node3
echo k8s-node3 > /etc/hostname

#修改系统参数
systemctl stop firewalld && systemctl disable firewalld
sed -i 's/^SELINUX=enforcing$/SELINUX=disabled/' /etc/selinux/config
setenforce 0
swapoff -a
yes | cp /etc/fstab /etc/fstab_bak 
cat /etc/fstab_bak |grep -v swap > /etc/fstab
 
cat < /etc/yum.repos.d/kubernetes.repo
[kubernetes]
name=Kubernetes
baseurl=https://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64/
enabled=1
gpgcheck=1
repo_gpgcheck=1
gpgkey=https://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg https://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg
EOF
yum clean all
yum makecache fast

#安装docker
yum -y install docker
cat  << EOF  > /etc/docker/daemon.json 
{
    "registry-mirrors": ["https://wyrsf017.mirror.aliyuncs.com"]
}
EOF
systemctl start docker
systemctl enable docker
docker version

安装kubelet-1.19.0 kubeadm-1.19.0 kubectl-1.19.0（建议和master节点的版本一致）

yum -y install kubelet-1.19.0 kubeadm-1.19.0 
systemctl restart kubelet
systemctl enable kubelet
systemctl daemon-reload
echo 1 > /proc/sys/net/bridge/bridge-nf-call-iptables

最后一步：将138接入到集群中

kubeadm join 192.168.206.130:6443 --token abcdef.0123456789abcdef --discovery-token-ca-cert-hash sha256:97a177b891f75f92f07e61aedbfc8a34cd35d6785d55b9cc829dcf532e1de5b9

3，130 master节点上查看集群信息：

 kubectl get nodes -o wide

 实验成功！