Grafana 连接 Prometheus + 主机监控 Dashboard

目标

配置 Prometheus 数据源，导入 Node Exporter Full 仪表盘，实现一键监控。

步骤一：添加数据源

1. 登录 Grafana http://localhost:3000
2. 左侧菜单 → Connections → Data Sources → Add data source
3. 选择 Prometheus
4. 填写 URL：
   • Docker 环境：http://host.docker.internal:9090（macOS/Windows）
   • Docker 环境：http://172.17.0.1:9090（Linux）
   • 同主机：http://localhost:9090
5. 点击 Save & Test，应显示绿色 "Data source is working"

步骤二：创建自定义 Dashboard（JSON 配置）

{
  "dashboard": {
    "title": "主机监控总览",
    "tags": ["prometheus", "node"],
    "timezone": "browser",
    "panels": [
      {
        "title": "CPU 使用率",
        "type": "timeseries",
        "targets": [
          {
            "expr": "100 - (avg by(instance)(rate(node_cpu_seconds_total{mode=\"idle\"}[5m])) * 100)",
            "legendFormat": "{{instance}}",
            "refId": "A"
          }
        ],
        "gridPos": {"h": 8, "w": 12, "x": 0, "y": 0}
      },
      {
        "title": "内存使用率",
        "type": "gauge",
        "targets": [
          {
            "expr": "100 * (1 - node_memory_MemAvailable_bytes / node_memory_MemTotal_bytes)",
            "refId": "A"
          }
        ],
        "fieldConfig": {
          "defaults": {
            "unit": "percent",
            "thresholds": {
              "steps": [
                {"color": "green", "value": null},
                {"color": "yellow", "value": 70},
                {"color": "red", "value": 90}
              ]
            }
          }
        },
        "gridPos": {"h": 8, "w": 6, "x": 12, "y": 0}
      },
      {
        "title": "磁盘使用率",
        "type": "timeseries",
        "targets": [
          {
            "expr": "100 * (1 - node_filesystem_avail_bytes{mountpoint=\"/\"} / node_filesystem_size_bytes{mountpoint=\"/\"})",
            "legendFormat": "{{instance}}",
            "refId": "A"
          }
        ],
        "gridPos": {"h": 8, "w": 6, "x": 18, "y": 0}
      }
    ]
  }
}

步骤三：导入社区 Dashboard

Grafana 社区有大量现成 Dashboard：

1. 左侧菜单 → Dashboards → New → Import
2. 输入 Dashboard ID（如 Node Exporter Full: 1860）
3. 选择 Prometheus 数据源
4. 导入

常用 Dashboard ID：

• 1860 - Node Exporter Full
• 11074 - Node Exporter for Prometheus
• 6417 - Kubernetes 集群监控

步骤四：配置告警通知

# grafana.ini（或环境变量）
[smtp]
enabled = true
host = smtp.example.com:587
user = alerts@example.com
password = your-password
from_address = grafana@example.com

# 环境变量方式：
# GF_SMTP_ENABLED=true
# GF_SMTP_HOST=smtp.example.com:587

然后在 Dashboard 面板的 Alert 标签页中创建告警规则。

预期效果

Dashboard 显示主机 CPU/内存/磁盘实时曲线，阈值变色，告警通道配置完成后可收到通知。