---
name: "up.Request.prototype.failMode"
area: "API"
kind: "Property"
parent: "up.Request class"
url: "https://unpoly.com/api/up.Request.prototype.failMode"
---
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# up.Request.prototype.failMode

The [mode](https://unpoly.com/api/up.Layer.prototype.mode.md) of the layer targeted by this request in case the server responds with an [error code](https://unpoly.com/learn/error-responses.md).

The value will be sent as an [`X-Up-Fail-Mode`](https://unpoly.com/api/X-Up-Fail-Mode.md) header.

---

## Value {#value}

### failMode {#failMode}

Type: string