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Create custom hostnames

There are several required steps before a custom hostname can become active. For more details, refer to our Get started guide.

To create a custom hostname:

  1. Log in to the Cloudflare dashboard and select your account.
  2. Select your Cloudflare for SaaS application.
  3. Navigate to SSL/TLS > Custom Hostnames.
  4. Click Add Custom Hostname.
  5. Add your customer’s hostname app.customer.com and set the relevant options, including:
  6. Click Add Custom Hostname.

For each custom hostname, Cloudflare issues two certificates bundled in chains that maximize browser compatibility (unless you upload custom certificates).

The primary certificate uses a P-256 key, is SHA-2/ECDSA signed, and will be presented to browsers that support elliptic curve cryptography (ECC). The secondary or fallback certificate uses an RSA 2048-bit key, is SHA-2/RSA signed, and will be presented to browsers that do not support ECC.

Hostnames over 64 characters

The Common Name (CN) restriction establishes a limit of 64 characters (RFC 5280). If you have a hostname that exceeds this length, you can set cloudflare_branding to true when creating your custom hostnames via API.

"ssl": {
"cloudflare_branding": true
}

Cloudflare branding means that sni.cloudflaressl.com will be added as the certificate Common Name (CN) and the long hostname will be included as a part of the Subject Alternative Name (SAN).