环境准备
准备两台服务器，一台用作k8smaster，一台用作k8snode。示例系统为Centos7。
IP | ROLE | |
|---|---|---|
192.168.2.131 | k8smaster | |
192.168.2.132 | k8snode |
机器配置
每台机器都需要执行如下命令
代码语言：javascript复制# 关闭防火墙
sudo systemctl stop firewalld
sudo systemctl disable firewalld
# 关闭selinux
# 永久 # 这是允许容器访问主机文件系统所必需的
sudo sed -i 's/enforcing/disabled/' /etc/selinux/config
# 临时
sudo setenforce 0
# 关闭swap
# 临时
sudo swapoff -a
# 永久
sudo sed -ri 's/.*swap.*/#&/' /etc/fstab
# 根据规划设置主机名
sudo hostnamectl set-hostname <hostname> #k8smaster k8snode
# 添加hosts
sudo cat >> /etc/hosts << EOF
192.168.2.131 k8smaster
192.168.2.132 k8snode
EOF
sudo 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
# 时间同步
sudo yum install ntpdate -y
sudo ntpdate time.windows.com
date # 查看时间安装Docker
代码语言：javascript复制sudo yum remove docker docker-common docker-selinux docker-engine
sudo yum install -y yum-utils device-mapper-persistent-data lvm2
# 使用阿里云的docker安装yum源
sudo yum-config-manager --add-repo http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo
sudo yum -y install docker-ce docker-ce-cli containerd.io
sudo systemctl enable docker
sudo systemctl start docker添加k8s yum源
每台机器都需要
代码语言：javascript复制sudo 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安装kubeadm，kubelet和kubectl
每台机器都需要
代码语言：javascript复制sudo yum install -y kubelet-1.24.0 kubeadm-1.24.0 kubectl-1.24.0
sudo systemctl enable kubelet部署k8s master
在master节点执行
代码语言：javascript复制kubeadm init
--apiserver-advertise-address=192.168.2.131
--image-repository registry.aliyuncs.com/google_containers
--kubernetes-version v1.24.0
--service-cidr=10.96.0.0/12
--pod-network-cidr=10.244.0.0/16执行可能会报错：
代码语言：javascript复制Kubeadm unknown service runtime.v1alpha2.RuntimeService
# 解决方法
# https://github.com/containerd/containerd/issues/4581
rm /etc/containerd/config.toml
systemctl restart containerd
输出 Your Kubernetes control-plane has initialized successfully! 表示master节点安装成功。
根据提示执行
代码语言：javascript复制mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config加入node节点
在node节点执行
代码语言：javascript复制kubeadm join 192.168.2.131:6443 --token 9ypuou.dv1aqg0w3f4k5woe
--discovery-token-ca-cert-hash sha256:4837358ffa2fce8e2a45be7a99b01b020ced7adf52c151ccdfc3b756108e3041把node节点加入集群。输出如下信息表示node节点加入集群成功。
代码语言：javascript复制[preflight] Running pre-flight checks
[preflight] Reading configuration from the cluster...
[preflight] FYI: You can look at this config file with 'kubectl -n kube-system get cm kubeadm-config -o yaml'
[kubelet-start] Writing kubelet configuration to file "/var/lib/kubelet/config.yaml"
[kubelet-start] Writing kubelet environment file with flags to file "/var/lib/kubelet/kubeadm-flags.env"
[kubelet-start] Starting the kubelet
[kubelet-start] Waiting for the kubelet to perform the TLS Bootstrap...
This node has joined the cluster:
* Certificate signing request was sent to apiserver and a response was received.
* The Kubelet was informed of the new secure connection details.
Run 'kubectl get nodes' on the control-plane to see this node join the cluster.查看节点信息
代码语言：javascript复制kubectl get nodes -o wide
NAME STATUS ROLES AGE VERSION INTERNAL-IP EXTERNAL-IP OS-IMAGE KERNEL-VERSION CONTAINER-RUNTIME
k8smaster NotReady control-plane 13m v1.24.0 192.168.2.131 <none> CentOS Linux 7 (Core) 3.10.0-1160.el7.x86_64 containerd://1.6.7
k8snode NotReady <none> 49s v1.24.0 192.168.2.132 <none> CentOS Linux 7 (Core) 3.10.0-1160.el7.x86_64 containerd://1.6.7目前节点状态还是 NotReady，还需要配置网络插件。
安装网络插件
代码语言：javascript复制# 在主节点执行
kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
# 输出
namespace/kube-flannel created
clusterrole.rbac.authorization.k8s.io/flannel created
clusterrolebinding.rbac.authorization.k8s.io/flannel created
serviceaccount/flannel created
configmap/kube-flannel-cfg created
daemonset.apps/kube-flannel-ds created
# 查看pod状态
kubectl get pods -n kube-system
# 输出
NAME READY STATUS RESTARTS AGE
coredns-74586cf9b6-fr5vk 0/1 Pending 0 16m
coredns-74586cf9b6-j8pxj 0/1 Pending 0 16m
etcd-k8smaster 1/1 Running 0 16m
kube-apiserver-k8smaster 1/1 Running 0 16m
kube-controller-manager-k8smaster 1/1 Running 0 16m
kube-proxy-6cpxh 1/1 Running 0 3m49s
kube-proxy-kbb82 1/1 Running 0 16m
kube-scheduler-k8smaster 1/1 Running 0 16m等待一段时间coredns状态ready之后即可。
最终所有pod状态都处于Running。
测试集群
至此，k8s单master集群已经安装完成，接下来通过部署一个nginx服务测试下集群是否可用。
master 执行
代码语言：javascript复制kubectl create deployment nginx --image=nginx
# 等待一段时间查看pod状态
kubectl get pod -o wide
pod状态为Running表示nginx已经部署完成。想要访问nginx服务还需要暴露外部访问端口
代码语言：javascript复制kubectl expose deployment nginx --port=80 --target-port=80 --type=NodePort
# 输出
service/nginx exposed
# 查看暴露的端口
kubectl get svcsvc是k8s里面的一种服务，用于pod访问。port是svc的端口，target-port是容器的端口，把port改为12345也是可行的，可以一试。以后有时间具体讲解。
通过集群的任一ip的30779端口即可访问到该nginx服务。
