> For the complete documentation index, see [llms.txt](https://surge.mitsea.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://surge.mitsea.com/policy-group/fallback.md).

# 可用性测试组

根据优先级和可用性选择一个可用的策略。可用性通过访问一个 URL 来测试，就像自动测试组一样。区别在于降级组只关心可用性，而不关心具体的延迟。定义在前面的策略具有高优先级。

`FallbackGroup = fallback, ProxySOCKS5, ProxySOCKS5TLS`

### 临时覆盖 (Temporary Override)

你可以通过手动选择策略来临时覆盖自动测试的结果。

* 在 Surge Mac 中，你可以在主菜单中对应的组里找到覆盖选项。
* 在 Surge iOS 中，你可以在策略组视图中长按对应策略的菜单找到覆盖选项。

### 参数

#### `interval`: 可选，单位为秒，默认值：600（秒）

决定多久之后丢弃基准测试结果。

#### `timeout`: 可选，单位为秒，默认值：5（秒）

如果在超时时间内未完成，则放弃该策略。


---

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Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

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