Let's Encrypt® sur cPanel® avec CloudFlare®
If the CloudFlare® CDN is activated on the domain: Let’s Encrypt® will be unable to run and renew the SSL certificate on the cPanel® server. This is problematic, especially because Let’s Encrypt® checks the IPv6 record too (and is not able to verify the domain if the server has no IPv6). However there is a simple solution: within CloudFlare® the real NS servers needs to be assigned to the following subdomains:
The DNS records will then rely on the cPanel® real NS servers.