# Jenkins Kubernetes部署文档

本目录包含Jenkins在Kubernetes集群上的部署配置和文档。

## 部署配置

### jenkins-deployment.yaml

```yaml
apiVersion: v1
kind: PersistentVolume
metadata:
  name: jenkins-pv
spec:
  capacity:
    storage: 20Gi
  accessModes:
    - ReadWriteOnce
  hostPath:
    path: /data/jenkins
  storageClassName: manual
---
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: jenkins-pvc
  namespace: default
spec:
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 20Gi
  storageClassName: manual
---
apiVersion: v1
kind: ServiceAccount
metadata:
  name: jenkins
  namespace: default
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
  name: jenkins
rules:
- apiGroups: [""]
  resources: ["pods"]
  verbs: ["create","delete","get","list","patch","update","watch"]
- apiGroups: [""]
  resources: ["pods/exec"]
  verbs: ["create","delete","get","list","patch","update","watch"]
- apiGroups: [""]
  resources: ["pods/log"]
  verbs: ["get","list","watch"]
- apiGroups: [""]
  resources: ["secrets"]
  verbs: ["get"]
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  name: jenkins
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: jenkins
subjects:
- kind: ServiceAccount
  name: jenkins
  namespace: default
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: jenkins
  namespace: default
spec:
  replicas: 1
  selector:
    matchLabels:
      app: jenkins
  template:
    metadata:
      labels:
        app: jenkins
    spec:
      serviceAccountName: jenkins
      containers:
      - name: jenkins
        image: jenkins/jenkins:lts
        ports:
        - containerPort: 8080
          name: http
        - containerPort: 50000
          name: agent
        env:
        - name: JENKINS_OPTS
          value: "--prefix=/jenkins"
        - name: JAVA_OPTS
          value: "-Xmx2048m"
        volumeMounts:
        - name: jenkins-data
          mountPath: /var/jenkins_home
        resources:
          requests:
            memory: "1Gi"
            cpu: "500m"
          limits:
            memory: "2Gi"
            cpu: "1000m"
      volumes:
      - name: jenkins-data
        persistentVolumeClaim:
          claimName: jenkins-pvc
---
apiVersion: v1
kind: Service
metadata:
  name: jenkins
  namespace: default
spec:
  type: NodePort
  ports:
  - port: 8080
    targetPort: 8080
    nodePort: 30280
    name: http
  - port: 50000
    targetPort: 50000
    nodePort: 30500
    name: agent
  selector:
    app: jenkins
```

## 部署步骤

### 1. 创建数据目录

```bash
mkdir -p /data/jenkins
```

### 2. 应用部署配置

将上述YAML配置保存为 `jenkins-deployment.yaml` 文件，然后执行：

```bash
kubectl apply -f jenkins-deployment.yaml
```

### 3. 验证部署状态

```bash
# 查看Pod状态
kubectl get pods -l app=jenkins

# 查看Service状态
kubectl get svc jenkins

# 查看详细信息
kubectl describe pod <jenkins-pod-name>
```

## 访问地址

| 服务 | 端口 | 说明 |
|------|------|------|
| Web界面 | 30280 | Jenkins Web界面（http://节点IP:30280/jenkins） |
| Agent | 30500 | Jenkins Agent连接端口 |

### 获取Jenkins初始密码

```bash
kubectl exec -it $(kubectl get pod -l app=jenkins -o jsonpath='{.items[0].metadata.name}') -- cat /var/jenkins_home/secrets/initialAdminPassword
```

首次访问Jenkins时，需要输入上述解锁密码，然后按照向导完成初始设置。

## 配置参数

| 参数 | 值 | 说明 |
|------|-----|------|
| 镜像 | jenkins/jenkins:lts | Jenkins LTS版本 |
| 数据目录 | /data/jenkins | HostPath存储路径 |
| 存储容量 | 20Gi | PV/PVC分配存储 |
| 内存请求 | 1Gi | 最小内存需求 |
| 内存限制 | 2Gi | 最大内存限制 |
| CPU请求 | 500m | 最小CPU需求 |
| CPU限制 | 1000m | 最大CPU限制 |
| 访问前缀 | /jenkins | URL访问路径前缀 |
| JVM堆内存 | -Xmx2048m | Java虚拟机堆内存设置 |

### RBAC权限配置

Jenkins配置了以下Kubernetes集群权限：
- **Pods操作**: create, delete, get, list, patch, update, watch
- **Pods执行**: create, delete, get, list, patch, update, watch
- **Pods日志**: get, list, watch
- **Secrets**: get

这些权限用于Jenkins在Kubernetes中执行CI/CD任务。

## 端口映射

| 容器端口 | NodePort | 用途 |
|----------|----------|------|
| 8080 | 30280 | Web界面 |
| 50000 | 30500 | Agent连接 |

## 常用管理命令

### 查看Pod状态

```bash
kubectl get pods -l app=jenkins
kubectl logs -f <jenkins-pod-name>
```

### 重启服务

```bash
kubectl rollout restart deployment jenkins
```

### 扩容/缩容

```bash
# 扩容到2个副本
kubectl scale deployment jenkins --replicas=2

# 缩容到1个副本
kubectl scale deployment jenkins --replicas=1
```

### 查看资源使用

```bash
kubectl top pods -l app=jenkins
```

### 备份数据

```bash
kubectl exec -it $(kubectl get pod -l app=jenkins -o jsonpath='{.items[0].metadata.name}') -- tar czf /tmp/jenkins-backup.tar.gz /var/jenkins_home
```

## 故障排查

### Pod无法启动

#### ImagePullBackOff

```bash
# 查看Pod详细信息
kubectl describe pod <jenkins-pod-name>

# 手动拉取镜像
docker pull jenkins/jenkins:lts

# 检查Docker镜像加速配置
cat /etc/docker/daemon.json
```

#### ContainerCreating状态持续

```bash
# 检查PV/PVC状态
kubectl get pv
kubectl get pvc

# 检查存储目录权限
ls -la /data/jenkins

# 调整目录权限
chmod -R 777 /data/jenkins
```

### 服务无法访问

```bash
# 检查Service状态
kubectl get svc jenkins

# 检查端口占用
netstat -tlnp | grep 30280

# 检查防火墙
iptables -L -n | grep 30280
```

### 性能问题

```bash
# 检查资源使用
kubectl top pods -l app=jenkins

# 检查Pod日志
kubectl logs <jenkins-pod-name>

# 调整资源限制
kubectl edit deployment jenkins
```

## 维护建议

### 定期备份

建议配置定期备份策略，配置Jenkins备份插件或定期导出配置。

### 监控告警

建议配置以下监控指标：
- **资源使用率**: CPU、内存、磁盘
- **Pod状态**: 运行状态、重启次数
- **服务可用性**: 访问延迟、错误率

### 升级策略

1. **镜像升级**: 更新Deployment中的镜像版本
2. **滚动更新**: 使用kubectl rollout实现零停机升级
3. **备份回滚**: 升级前先备份，失败时快速回滚

```bash
# 滚动更新
kubectl set image deployment/jenkins jenkins=jenkins/jenkins:2.401.1

# 回滚
kubectl rollout undo deployment/jenkins
```

## 版本信息

| 项目 | 版本 |
|------|------|
| 文档版本 | v1.0 |
| Jenkins | lts |
| 更新日期 | 2026-01-09 |