> ## Documentation Index
> Fetch the complete documentation index at: https://docs.gcore.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Integrate a CDN resource with Webasyst

> Connect a Gcore CDN resource to Webasyst by setting the CDN field to a custom domain and verifying asset URLs.

Webasyst can direct image, CSS, and JavaScript URLs generated by the Site app to a Gcore CDN [custom domain](/cdn/cdn-resource-options/general/create-and-set-a-custom-domain-for-the-content-delivery-via-cdn) through the **CDN** field. Create a [CDN resource](/cdn/getting-started/create-a-cdn-resource/create-a-cdn-resource) before starting the integration.

> [!WARNING]
>
> Back up the site files and database before making changes. These steps assume the default Site app settings layout; the **CDN** setting affects generated asset URLs, while hardcoded absolute URLs in custom themes require separate updates.

Before configuring Webasyst, collect the complete HTTPS URL to enter in the **CDN** field: `https://cdn.site.com`.

**1. Open the CDN resource**

In the [Gcore Customer Portal](https://portal.gcore.com), navigate to **CDN** > **CDN resources** and open the resource.

**2. Copy the custom domain**

Note the **custom domain** shown for the resource and form its complete URL by adding the `https://` prefix: `https://cdn.site.com`.

**3. Confirm the DNS CNAME**

Confirm that the custom domain has a CNAME record pointing to the Gcore target hostname shown in the Customer Portal (`cl-****.gcdn.co`). Do not put the `gcdn.co` hostname in Webasyst.

**4. Confirm SSL**

Confirm the custom domain has a valid SSL certificate so assets can load over HTTPS.

**5. Verify origin access**

Request a known CSS, JavaScript, or image path directly from the protocol and hostname configured as the CDN origin:

```text theme={null}
https://origin.example.com/path/to/known-asset.css
```

Continue only after the origin returns the expected file without a `403` or `404` response.

Then configure Webasyst:

**1. Open the Site settings**

Log in to the Webasyst administration area, open the **Site** app, and select **Settings**.

**2. Enter the CDN URL**

In the **CDN** field, enter the complete custom domain URL copied from the Customer Portal: `https://cdn.site.com`.

**3. Save the configuration**

Save the settings.

**4. Confirm the integration**

1. Open the browser developer tools.
2. Select the **Network** tab.
3. Refresh the page.
4. Confirm that Webasyst-generated asset URLs load from the custom domain instead of the original domain.
5. Update any hardcoded absolute asset URLs in custom theme files separately.