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# 实例是否存活，其操作系统运行状态如何？

## Uptime — Running for

Guest 自上次启动以来的运行时长。用于确认实例近期是否发生过重启。

Uptime 面板还会显示 QEMU Guest Agent（QGA）是否已安装以及数据采集是否已启用。若未安装 QGA，本 Dashboard 上的 Guest 内部面板（CPU、内存、Swap、负载均值、TCP 连接数、文件系统使用率）将为空——请安装 QGA 并启用数据采集以填充这些面板。

## TCP Connections

Guest 内部已建立的 TCP 套接字数量。这是最低成本的"该服务器是否真的在为任何人服务"信号，也是长期运行服务中连接泄漏 Bug 的早期预警。

## API 参考

| Console 面板           | API                         | metricType        | 备注           |
| -------------------- | --------------------------- | ----------------- | ------------ |
| Uptime — Running for | —                           | —                 | 仅 Console 可用 |
| TCP Connections      | DescribeInstanceMonitorData | `TCP_ESTABLISHED` |              |


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