Add prerendered error page setting for node

src/content/docs/en/basics/astro-pages.mdx

@@ -103,7 +103,7 @@ This will build to a `404.html` page. Most [deploy services](/en/guides/deploy/)
 
 ## Custom 500 Error Page
 
-For a custom 500 error page to show for pages that are [rendered on demand](/en/guides/on-demand-rendering/), create the file `src/pages/500.astro`. This custom page is not available for prerendered pages and can't be prerendered.
+For a custom 500 error page to show for pages that are [rendered on demand](/en/guides/on-demand-rendering/), create the file `src/pages/500.astro`. This custom page is not available for prerendered pages.
 
 If an error occurs rendering this page, your host's default 500 error page will be shown to your visitor.
 

src/content/docs/en/guides/integrations-guide/node.mdx

@@ -160,6 +160,34 @@ export default defineConfig({
 });
 ```
 
+### `experimentalErrorPageHost`
+
+<p>
+  **Type:** `string | URL` <br />
+  **Default:** `undefined`<br />
+  <Since v="9.4.0" pkg="@astrojs/node"/>
+</p>
+
+Specifies an alternate host for loading prerendered [custom error pages](/en/basics/astro-pages/#custom-404-error-page).
+
+Astro needs to be able to load your 404 page in order to return it in a response. By default, Astro will load prerendered custom error pages from the same host as the one that the request is made to. For example, if a request is made to `https://example.com/nonexistent-page`, Astro will attempt to load the prerendered error page from `https://example.com/404.html`.
+
+Use `experimentalErrorPageHost` when your custom error page must be loaded from a different host, such as when the server is running behind a reverse proxy or in a container that may not have access to the external host URL. You can also use this when it is more efficient to load the prerendered error page from localhost rather than via the public internet.
+
+The value can be a string or a URL object. It must be a fully-qualified URL, including the protocol (e.g., `http://localhost:4321`). Astro will always load the prerendered error page from the root path, and any path or query parameters will be ignored.
+
+```js
+import { defineConfig } from 'astro/config';
+import node from '@astrojs/node';
+
+export default defineConfig({
+  adapter: node({
+    // Load pages from localhost, not the public URL.
+    experimentalErrorPageHost: 'http://localhost:4321',
+  })
+});
+```
+
 ## Usage
 
 First, [performing a build](/en/guides/deploy/#building-your-site-locally). Depending on which `mode` selected (see above) follow the appropriate steps below: