基于k3s部署Nginx、MySQL、Golang和Redis的详细教程

1. 安装k3s集群

1.1 安装k3s（单节点快速体验）

bash 复制代码

# 使用root用户或sudo执行
curl -sfL https://get.k3s.io | sh -

# 验证安装
sudo kubectl get nodes  # 应显示一个节点状态为Ready
sudo systemctl status k3s

1.2 设置kubectl快捷方式（可选）

bash 复制代码

mkdir -p ~/.kube
sudo cp /etc/rancher/k3s/k3s.yaml ~/.kube/config
sudo chown $USER ~/.kube/config
export KUBECONFIG=~/.kube/config

2. 部署MySQL数据库

2.1 创建持久化存储卷（PVC）

yaml 复制代码

# mysql-pvc.yaml
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: mysql-pvc
spec:
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 2Gi  # 生产环境建议5Gi以上

bash 复制代码

kubectl apply -f mysql-pvc.yaml

2.2 创建数据库密码Secret

bash 复制代码

kubectl create secret generic mysql-secret \
  --from-literal=root_password=your_secure_password \
  --from-literal=database=appdb

2.3 部署MySQL

yaml 复制代码

# 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:8.0
          env:
            - name: MYSQL_ROOT_PASSWORD
              valueFrom:
                secretKeyRef:
                  name: mysql-secret
                  key: root_password
            - name: MYSQL_DATABASE
              valueFrom:
                secretKeyRef:
                  name: mysql-secret
                  key: database
          ports:
            - containerPort: 3306
          volumeMounts:
            - mountPath: /var/lib/mysql
              name: mysql-data
      volumes:
        - name: mysql-data
          persistentVolumeClaim:
            claimName: mysql-pvc
---
apiVersion: v1
kind: Service
metadata:
  name: mysql-service
spec:
  selector:
    app: mysql
  ports:
    - port: 3306
      targetPort: 3306
  type: ClusterIP

bash 复制代码

kubectl apply -f mysql-deployment.yaml

3. 部署Redis缓存

3.1 创建Redis持久化存储

yaml 复制代码

# redis-pvc.yaml
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: redis-pvc
spec:
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 1Gi

bash 复制代码

kubectl apply -f redis-pvc.yaml

3.2 部署Redis

yaml 复制代码

# redis-deployment.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: redis-deployment
spec:
  replicas: 1
  selector:
    matchLabels:
      app: redis
  template:
    metadata:
      labels:
        app: redis
    spec:
      containers:
        - name: redis
          image: redis:alpine
          ports:
            - containerPort: 6379
          volumeMounts:
            - mountPath: /data
              name: redis-data
          command: ["redis-server", "--appendonly yes"]  # 启用持久化
      volumes:
        - name: redis-data
          persistentVolumeClaim:
            claimName: redis-pvc
---
apiVersion: v1
kind: Service
metadata:
  name: redis-service
spec:
  selector:
    app: redis
  ports:
    - port: 6379
      targetPort: 6379
  type: ClusterIP

bash 复制代码

kubectl apply -f redis-deployment.yaml

4. 部署Golang应用

4.1 准备Golang Docker镜像

创建示例Golang应用 main.go：

go 复制代码

package main

import (
    "fmt"
    "net/http"
    "database/sql"
    _ "github.com/go-sql-driver/mysql"
    "github.com/redis/go-redis/v9"
)

func handler(w http.ResponseWriter, r *http.Request) {
    // 连接MySQL
    db, _ := sql.Open("mysql", "root:${MYSQL_ROOT_PASSWORD}@tcp(mysql-service:3306)/${MYSQL_DATABASE}")
    defer db.Close()
    
    // 连接Redis
    rdb := redis.NewClient(&redis.Options{Addr: "redis-service:6379"})
    defer rdb.Close()
    
    fmt.Fprintf(w, "Connected to MySQL and Redis!")
}

func main() {
    http.HandleFunc("/", handler)
    http.ListenAndServe(":8080", nil)
}

创建 Dockerfile：

dockerfile 复制代码

FROM golang:1.20-alpine AS builder
WORKDIR /app
COPY . .
RUN go mod init app && go mod tidy
RUN CGO_ENABLED=0 GOOS=linux go build -o /app/main

FROM alpine:latest
COPY --from=builder /app/main /app/main
EXPOSE 8080
CMD ["/app/main"]

构建并推送镜像到仓库（或本地构建）：

bash 复制代码

docker build -t yourusername/golang-app:v1 .
docker push yourusername/golang-app:v1

4.2 部署Golang应用到k3s

yaml 复制代码

# golang-deployment.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: golang-deployment
spec:
  replicas: 2
  selector:
    matchLabels:
      app: golang
  template:
    metadata:
      labels:
        app: golang
    spec:
      containers:
        - name: golang
          image: yourusername/golang-app:v1  # 替换为你的镜像
          ports:
            - containerPort: 8080
          env:
            - name: MYSQL_ROOT_PASSWORD  # 从Secret注入
              valueFrom:
                secretKeyRef:
                  name: mysql-secret
                  key: root_password
            - name: MYSQL_DATABASE
              valueFrom:
                secretKeyRef:
                  name: mysql-secret
                  key: database
          livenessProbe:  # 健康检查
            httpGet:
              path: /
              port: 8080
            initialDelaySeconds: 10
            periodSeconds: 5
---
apiVersion: v1
kind: Service
metadata:
  name: golang-service
spec:
  selector:
    app: golang
  ports:
    - port: 8080
      targetPort: 8080
  type: ClusterIP

bash 复制代码

kubectl apply -f golang-deployment.yaml

5. 部署Nginx反向代理

5.1 创建Nginx配置文件

yaml 复制代码

# nginx-config.yaml
apiVersion: v1
kind: ConfigMap
metadata:
  name: nginx-config
data:
  default.conf: |
    server {
        listen 80;
        server_name localhost;

        location / {
            proxy_pass http://golang-service:8080;  # 转发到Golang服务
            proxy_set_header Host $host;
            proxy_set_header X-Real-IP $remote_addr;
        }
    }

bash 复制代码

kubectl apply -f nginx-config.yaml

5.2 部署Nginx

yaml 复制代码

# 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:alpine
          ports:
            - containerPort: 80
          volumeMounts:
            - mountPath: /etc/nginx/conf.d
              name: nginx-config
      volumes:
        - name: nginx-config
          configMap:
            name: nginx-config
---
apiVersion: v1
kind: Service
metadata:
  name: nginx-service
spec:
  selector:
    app: nginx
  ports:
    - port: 80
      targetPort: 80
  type: NodePort  # 或LoadBalancer

bash 复制代码

kubectl apply -f nginx-deployment.yaml

6. 验证部署

6.1 查看所有资源状态

bash 复制代码

kubectl get pods,svc,pvc

确保所有Pod状态为 Running，服务正常启动。

6.2 访问应用

bash 复制代码

# 获取Nginx的NodePort
kubectl get svc nginx-service -o jsonpath='{.spec.ports[0].nodePort}'

# 访问应用（假设节点IP为192.168.1.100，NodePort为30007）
curl http://192.168.1.100:30007

预期输出：Connected to MySQL and Redis!

7. 扩展与维护

7.1 扩容Golang副本

bash 复制代码

kubectl scale deployment golang-deployment --replicas=3

7.2 更新Golang应用

修改代码后重新构建镜像：

bash 复制代码

docker build -t yourusername/golang-app:v2 .
docker push yourusername/golang-app:v2

更新Deployment镜像版本：

bash 复制代码

kubectl set image deployment/golang-deployment golang=yourusername/golang-app:v2

8. 关键配置说明

组件	核心配置项	作用说明
MySQL	`persistentVolumeClaim`	数据持久化到PVC
Redis	`command: ["redis-server", "--appendonly yes"]`	启用AOF持久化
Golang	`livenessProbe`	自动重启不健康的Pod
Nginx	`proxy_pass http://golang-service`	反向代理到后端服务

附：常见问题排查

Golang无法连接MySQL/Redis
- 检查服务名称是否正确（mysql-service、redis-service）
- 验证Secret中的密码是否匹配
bash 复制代码
```
kubectl exec -it <golang-pod> -- env | grep MYSQL_ROOT_PASSWORD
```
Nginx返回502错误
- 检查Golang服务是否正常运行：
  bash 复制代码
```
kubectl logs <golang-pod>
```
持久化存储未生效
- 确认PVC状态是否为 Bound：
  bash 复制代码
```
kubectl get pvc
```