# Origin Host Header

The Origin Host Header feature allows you to define a custom domain to be sent in the `Host` header of requests forwarded to your origin. Many origin servers rely on the `Host` header for routing, virtual hosting, or tenant identification.\
When this option is enabled and a domain is provided, the CDN replaces the default host value with the one you specify.

The feature does not modify viewer-facing responses and does not affect caching behavior.

## How Origin Host Header Works

You can configure X-CDN Header in the [Medianova Control Panel](https://cloud.medianova.com) or via [API](https://clients.medianova.com/api-documentation/performance-cdn/headers#put-api-v1-cdn-organization_uuid-resource-resource_uuid-3)

When the feature is active:

* The CDN overwrites the `Host` header in the **origin request** with the domain you provide.
* The domain must be entered **without** `http://` or `https://`.
* The configured value is applied to all origin fetches for the selected CDN Resource.
* The behavior supports any valid domain that your origin server expects for routing or validation.

The purpose of this feature is to ensure compatibility with origins that require a specific hostname, especially in environments where multiple sites share the same origin infrastructure.

<figure><img src="/files/DqWFNgqxkIfvnMBuRyxm" alt="" width="563"><figcaption><p>Origin Host Header field enabled with sample domain</p></figcaption></figure>

### Use Cases

#### Virtual hosting environments

Ensure the correct site is selected when multiple hostnames share the same origin.

#### Multi-tenant systems

Send a tenant-specific domain in the Host header for proper routing.

#### Origin behavior validation

Match the exact hostname your origin expects for SSL/SNI evaluation or application routing logic (when applicable to host header usage).

### Notes

* Enter only the domain name (e.g., `subdomain.example.com`).
* Do **not** include URL schemes such as `http://` or `https://`.
* This feature modifies only the **origin-bound request** and does not impact the viewer response.
* Incorrect domain entries may cause the origin to respond with errors or unexpected routing behavior.


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