table of Contents
Introduction to kubeadm deployment method
Sixth, the chain that passes bridged IPv4 traffic to iptables:
8. Install Docker/kubeadm/bubelet on all nodes
Introduction to kubeadm deployment method
Kubeadm is a tool for rapid deployment of kubernetes clusters launched by the official community. This tool can complete the deployment of a Kubernetes cluster with two instructions:
First, create a Master node kubeadm init
Second, join the Node node to the current cluster $ kubeadm join <IP and port of the Master node>
Installation requirements
Before starting, the deployment of Kubernetes cluster machines needs to meet the following conditions, which are the prerequisites for deploying Kubernetes clusters, otherwise the installation cannot be successful.
1 One or more machines, operating system CentOS7.x-86_x64
2 Hardware configuration: 2GB or more RAM, 2 CPU or more CPU, hard disk 30GB or more
3 Network communication between all machines in the cluster
4 Can access the external network, need to pull the mirror
5 Prohibit swap partition
Ultimate goal
1 Install Docker and kubeadm on all nodes
2 Deploy Kubernetes Master
3 Deploy the container network plugin
4 Deploy Kubernetes Node and add the node to the Kubernetes cluster
Organization
In this case, three servers are required to deploy cluster kubernetes. Here I use virtual machine deployment. The corresponding roles of each virtual machine are as follows
k8s-master 192.168.30.128
k8s-node1 192.168.30.129
k8s-node2 192.168.30.130
system initialization
Turn off the firewall
systemctl stop firewalld
systemctl disable firewalldTwo close selinux
sed -i 's/enforcing/disabled/' /etc/selinux/config # 永久
setenforce 0Three close swap
swapoff -a #临时
vim /etc/fstab #永久 注释掉文件中swap行Four set the host name
hostnamectl set-hostname xxx # 不同虚拟机设置不同的主机名Five add hosts to the master:
cat >> /etc/hosts << EOF
192.168.30.128 k8s-master
192.168.30.129 k8s-node1
192.168.30.130 k8s-node2
EOF
Sixth, the chain that passes bridged IPv4 traffic to iptables:
cat > /etc/sysctl.d/k8s.conf << EOF
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
EOF
sysctl --system # 生效
Seven time synchronization
yum install ntpdate -y
ntpdate time.windows.com8. Install Docker/kubeadm/bubelet on all nodes
Kubernetes default CRI (container runtime) is Docker, so install Docker first.
- 1 Install Docker
# step 1: 安装必要的一些系统工具
sudo yum install -y yum-utils device-mapper-persistent-data lvm2
# Step 2: 添加软件源信息
sudo yum-config-manager --add-repo http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo
# Step 3: 更新并安装 Docker-CE
sudo yum makecache fast
sudo yum -y install docker-ce-18.06.1.ce-3.el7
# Step 4: 开启Docker服务
sudo service docker start- 2 Add Alibaba Cloud yum software source
sudo mkdir -p /etc/docker
sudo tee /etc/docker/daemon.json <<-'EOF'
{
"registry-mirrors": ["https://gk0lyeuc.mirror.aliyuncs.com"]
}
EOF
sudo systemctl daemon-reload
sudo systemctl restart docker- 3 Add kubernetes source
cat > /etc/yum.repos.d/kubernetes.repo << EOF
[kubernetes]
name=Kubernetes
baseurl=https://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64
enabled=1
gpgcheck=0
repo_gpgcheck=0
gpgkey=https://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg https://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg
EOF
- 4 Install kubeadm, kubelet and kubectl
yum install -y kubelet-1.16.0 kubeadm-1.16.0 kubectl-1.16.0
systemctl enable kubelet- 5 Deploy Kubernetes Master
kubeadm init --apiserver-advertise-address=192.168.30.128 --image-repository registry.aliyuncs.com/google_containers --kubernetes-version v1.18.0 --service-cidr=10.96.0.0/12 --pod-network-cidr=10.244.0.0/16Since the default pull mirror address k8s.gcr.io cannot be accessed in China, specify the Alibaba Cloud mirror warehouse address here.
5.1 Use kubectl tool
mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config
kubectl get nodes- Six install pod network plug-in
sudo kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
- Seven join Kubernetes Node
At 192.168.30.129/130 (Node), add a new node to the cluster and execute the kubeadm join command output in kubeadm init:
kubeadm join 192.168.30.128:6443 --token esce21.q6hetwm8si29qxwn \
--discovery-token-ca-cert-hash sha256:00603a05805807501d7181c3d60b478788408cfe6cedefedb1f97569708be9c5- Eight test Kubernetes cluster
Create a pod in the Kubernetes cluster and verify that it is running normally:
kubectl create deployment nginx --image=nginx
kubectl expose deployment nginx --port=80 --type=NodePort
kubectl get pod,svc
Visit address: http://NodeIP:Port
As you can see, kubeadm has successfully built a cluster, and has created a pod node, and can access it normally.