While Cloudflare can be used to accelerate and protect most subdomains, there are certain types of subdomains or specific situations where enabling Cloudflare might not be suitable or may require additional configuration. Here are some examples:
- Mail or FTP subdomains: Cloudflare is primarily designed for HTTP/HTTPS traffic, and it doesn't support proxying for mail (IMAP, POP3, or SMTP) or FTP subdomains. You should not enable Cloudflare for subdomains like mail.example.com or ftp.example.com.
- Subdomains requiring non-HTTP services: If a subdomain is used for non-HTTP services, such as SSH or custom TCP/UDP services, you should not enable Cloudflare for it, as Cloudflare only proxies HTTP/HTTPS traffic.
- Wildcard subdomains: Cloudflare doesn't proxy wildcard subdomains by default. If your website relies on wildcard subdomains, you'll need to add each subdomain individually in Cloudflare or upgrade to an Enterprise plan that supports wildcard subdomains.
- Third-party services: Some third-party services might have specific requirements or restrictions that could make them incompatible with Cloudflare. In these cases, you should consult the service's documentation or support team for guidance.
In general, when deciding whether to enable Cloudflare for a subdomain, consider its purpose, the type of traffic it handles, and any potential compatibility issues with third-party services. If you're unsure, it's best to consult Cloudflare's documentation or contact their support team for guidance.
