引言

随着云计算和容器技术的快速发展，Kubernetes（K8s）已成为云原生时代的核心引擎。本文将为您详细介绍如何在CentOS上轻松上手Kubernetes，并实战容器编排，开启高效运维之旅。

环境准备

1. 系统要求

• 操作系统：CentOS 7
• 硬件要求：2核CPU，4GB内存
• 网络要求：公网IP或者内网访问

2. 系统配置

• 更新系统：sudo yum update -y
• 安装Docker：sudo yum install -y docker
• 启动Docker服务：sudo systemctl start docker
• 设置Docker开机自启：sudo systemctl enable docker

Kubernetes集群搭建

1. 安装kubeadm、kubelet和kubectl

• 安装kubeadm：sudo yum install -y kubeadm
• 安装kubelet：sudo yum install -y kubelet
• 安装kubectl：sudo yum install -y kubectl

2. 初始化集群

• 设置集群名称：export CLUSTER_NAME=myk8s
• 初始化集群：sudo kubeadm init --pod-network-cidr=10.244.0.0/16
• 将kubeconfig文件添加到当前用户：sudo cp /etc/kubernetes/admin.conf ~/$USER/.kube/config

3. 安装网络插件

• 安装Flannel网络插件：kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml

容器编排实战

1. 部署Nginx服务

• 创建Nginx部署文件：`cat < nginx-deployment.yaml apiVersion: apps/v1 kind: Deployment metadata: name: nginx-deployment spec: replicas: 2 selector: matchLabels: app: nginx template: metadata: labels:

  app: nginx
  

  spec: containers:

   - name: nginx
  image: nginx:1.17.1
  ports:
  - containerPort: 80
  

  EOF`

• 部署Nginx服务：kubectl apply -f nginx-deployment.yaml

2. 部署MySQL服务

• 创建MySQL部署文件：`cat < mysql-deployment.yaml apiVersion: apps/v1 kind: Deployment metadata: name: mysql-deployment spec: replicas: 1 selector: matchLabels: app: mysql template: metadata: labels:

  app: mysql
  

  spec: containers:

   - name: mysql
  image: mysql:5.7
  ports:
  - containerPort: 3306
  

  EOF`

• 部署MySQL服务：kubectl apply -f mysql-deployment.yaml

3. 部署Ingress控制器

• 创建Ingress控制器部署文件：`cat < ingress-nginx-deployment.yaml apiVersion: apps/v1 kind: Deployment metadata: name: ingress-nginx spec: replicas: 2 selector: matchLabels: app: ingress-nginx template: metadata: labels:

  app: ingress-nginx
  

  spec: containers:

   - name: nginx
  image: nginx-ingress-controller:0.27.0
  ports:
  - containerPort: 80
  

  EOF`

• 部署Ingress控制器：kubectl apply -f ingress-nginx-deployment.yaml

4. 配置Ingress规则

• 创建Ingress规则文件：`cat < ingress.yaml apiVersion: networking.k8s.io/v1 kind: Ingress metadata: name: nginx-ingress spec: rules:

  • host: nginx.example.com http: paths:
    • path: / pathType: Prefix backend: service: name: nginx-deployment port: number: 80 EOF`

• 应用Ingress规则：kubectl apply -f ingress.yaml

总结

本文详细介绍了在CentOS上轻松上手Kubernetes，并实战容器编排的过程。通过本文的学习，您可以开启云原生时代高效运维之旅，为您的企业构建稳定、可靠的容器化应用。