Fixing the "CDN Acceleration Is Not Enabled" error

If you're seeing an error message indicating that CDN acceleration isn't detected on your website even after installing and setting up the ClearFront WordPress plugin, this guide will help you troubleshoot and resolve the issue.

Common Causes

This issue typically arises in the following scenarios:

1 - Direct Origin Access

You may be accessing your WordPress admin panel without routing traffic through ClearFront. This often occurs if:

• DNS settings have not yet propagated.
• Your computer has a stale DNS entry.
• A static IP address for your domain is defined in your computer’s hosts file.

2 - CDN Acceleration Not Properly Configured

The plugin cannot detect ClearFront CDN because your DNS settings are incomplete or misconfigured. This includes records that aren’t properly configured for CDN acceleration. 

3 - Web Server Altering Headers

If your site is behind a reverse proxy (e.g., Cloudflare, NGINX, or a load balancer), it might strip or modify headers used by ClearFront to confirm CDN usage.

Solutions

Try the following troubleshooting steps to resolve the issue:

1 - Clear Your DNS Cache

• On Windows: ipconfig /flushdns
• On macOS: sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder
• On Linux: Restart the nscd or systemd-resolved service.

Then, restart your browser or clear its cache.

2 - Verify ClearFront DNS and CDN Settings

• Go to the DNS section in your ClearFront dashboard.
• Make sure the DNS record pointing to your site has the green CDN Proxy icon enabled.
• If not, edit the DNS record and enable CDN Acceleration.

3 - Move Images Back to the WordPress Server (Optional)

If you're testing or troubleshooting, you can temporarily revert media delivery from ClearFront back to your origin WordPress server.