kubernetes（k8s）集群中添加节点

向k8s集群中添加节点，有时候会遇到各种问题，因此总结了下步骤。

step1 准备工作

setenforce 0
sed -i --follow-symlinks 's/SELINUX=enforcing/SELINUX=disabled/g' /etc/sysconfig/selinux
firewall-cmd --permanent --add-port=6783/tcp
firewall-cmd --permanent --add-port=10250/tcp
firewall-cmd --permanent --add-port=10255/tcp
firewall-cmd --permanent --add-port=30000-32767/tcp
firewall-cmd --reload

step2 安装Docker-CE 和 Kubernetes Repo

dnf config-manager --add-repo=https://download.docker.com/linux/centos/docker-ce.repo

dnf install https://download.docker.com/linux/centos/7/x86_64/stable/Packages/containerd.io-1.2.6-3.3.el7.x86_64.rpm

dnf install docker-ce

systemctl enable docker
systemctl start docker

cat <<EOF > /etc/yum.repos.d/kubernetes.repo
[kubernetes]
name=Kubernetes
baseurl=https://packages.cloud.google.com/yum/repos/kubernetes-el7-x86_64
enabled=1
gpgcheck=1
repo_gpgcheck=1
gpgkey=https://packages.cloud.google.com/yum/doc/yum-key.gpg https://packages.cloud.google.com/yum/doc/rpm-package-key.gpg
EOF

Step 3: 安装 Kubeadm

dnf install kubeadm -y 
systemctl enable kubelet
systemctl start kubelet

Step 4: kubeadm join

kubeadm join 9.30.215.42:6443 --token ev0gfr.gcj977p481tamyvj --discovery-token-ca-cert-hash sha256:3cfb83830bbf46b95b0a0303ddd3752301a2ec345c104b14e0abb0094627bf3d

kubectl get nodes

注意

• 若出现以下问题：

[root@Node2 ~]# kubectl get nodes
The connection to the server localhost:8080 was refused - did you specify the right host or port?

极大概率是权限问题，可以将master节点的/etc/kubernetes/admin.conf复制到当前节点相应目录，再执行命令：

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