GUIDE · WORDPRESS · NO DNS

A CDN for WordPress without touching DNS

Not everyone can — or wants to — repoint their domain at a CDN: someone else runs the DNS, an agency manages the hosting, or you simply want to try it before moving anything. Since version 1.1.0, the official WordPress plugin serves your static assets from the edge without changing a single record.

What this mode actually does

The “Serve static assets through CDN” mode rewrites, in your rendered pages, the URLs of assets under wp-content/ and wp-includes/ so the browser fetches them from your property’s CDN hostname instead of your web host:

The CDN fetches each asset once from your origin (your WordPress site), caches it at the edge and serves it from the PoP nearest to each visitor. Your HTML keeps coming from your host, exactly as before. Because the *.prdrm.net hostname is the system hostname every property gets, this works the moment the property exists: themes, plugin assets, uploaded images and core scripts — typically the bulk of page weight — get edge caching and compression.

Install the plugin

Paradarum CDN Purge is the official plugin and lives in the WordPress directory: wordpress.org/plugins/paradarum-cdn-purge. Version 1.1.0, requires WordPress 5.6+ and PHP 7.4+, GPL-2.0-or-later.

1. In your WordPress admin, go to Plugins → Add New and search for “Paradarum CDN Purge” (or use Upload Plugin with the zip).
2. Click Install Now, then Activate.
3. Open Settings → Paradarum CDN to configure it.

Configure it: API key, property and hostname

Under Settings → Paradarum CDN you need three values:

• API key — an account key of the form pdm_…, created in the panel. The plugin stores it encrypted (AES-256-CBC) in the database.
• Property ID — the numeric ID of the property serving this site, visible in the panel when you open it.
• CDN hostname — when you turn the assets mode on, the field defaults to your property’s system hostname (my-site.prdrm.net). That is all: there is no DNS to touch.

Then flip Serve static assets through CDN on, save, reload a page on your site and view the source: URLs under wp-content and wp-includes now point at the CDN hostname. The only prerequisite is that the property’s origin points at this WordPress site — if you created it with the wizard, it already does.

What it rewrites — and what it does not

The mode rewrites only the assets under wp-content/ (themes, plugins, uploads) and wp-includes/ (core scripts and styles). Everything else stays untouched and keeps being served by your host:

• the HTML documents of your pages and posts,
• wp-admin and the login,
• REST and AJAX endpoints,
• any URL outside those two paths.

The split is deliberate: assets — which do not vary per visitor — go to the edge; everything dynamic stays on your server. That is why this mode cannot break sessions or carts: it never touches anything user-dependent.

Automatic purging comes built in

The plugin is not just the CDN mode: its core job is invalidating the cache when you publish. Editing a post purges the post URL and also the home page, the category and tag archives, feeds and the sitemap — each group can be excluded in the settings. It also registers the wp paradarum command for WP-CLI:

The next step: the whole site behind a CNAME

When you want the HTML served from the edge too — page caching, WAF and Always Online in front of the whole site — the upgrade is connecting your domain with a CNAME to the same my-site.prdrm.net. Once the hostname is Active (verified, certificate issued), you can set it as the plugin’s CDN hostname instead of the system one. The assets mode is the natural first step: you test the CDN with real traffic and repoint the domain once it has earned it.

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