Service and Proxy Subdomains

Last modified: March 15, 2024


Overview

Service subdomains provide access to cPanel & WHM interfaces and services. When you create accounts or domains, the system also creates their service subdomains. You can access interfaces and services via the port or the service subdomain. The port has a faster server response time. However, the service subdomain allows access from behind a firewall restricting, for example, port 80 and port 443.

  • SSL virtualhost configurations use the cPanel service SSL certificate. For example, the cpanel, whm, webdisk, and webmail service subdomains use it. For steps to bypass this, read the Bypass using the cPanel service SSL certificate section below.
  • The system handles SSL and non-SSL connections separately.
  • Each service subdomain’s virtualhost binds to the server’s assigned IP addresses.
  • cPanel & WHM uses Apache’s configuration to enable service subdomains with SSL.
  • cPanel & WHM uses Domain TLS SNI by default for service subdomains’ SSL certificates.
  • cPanel & WHM previously referred to service subdomains as proxy subdomains.

Settings

The Service subdomains setting is enabled by default in WHM’s Tweak Settings interface (WHM » Home » Server Configuration » Tweak Settings). We strongly recommend that you do not disable this setting.

In cPanel & WHM version 120 and later, we enable AutoConfig and Autodiscover by default. For more information, read the Domains section of our Tweak Settings documentation.

Note:
  • You can use the /usr/local/cpanel/scripts/servicedomains script to create DNS records for service subdomains.
  • If your server runs NGINX®, you cannot use the Safari® web browser to log in to a service subdomain. Use another browser, or log in with the service’s port URL.

Access interfaces

Users can access cPanel, WHM, and Webmail using these service subdomains:

Interface Service subdomain Secure port Non-secure port
cPanel https://cpanel.example.com https://example.com:2083 http://example.com:2082
WHM https://whm.example.com
Note:
SSL only secures the whm service subdomain for resellers.
https://example.com:2087 http://example.com:2086
Webmail https://webmail.example.com https://example.com:2096 http://example.com:2095

Access services

You can access cPanel & WHM services using these service subdomains:

Service Service subdomain Secure port Non-secure port
AutoConfig https://autoconfig.example.com https://example.com:443 http://example.com:443
Autodiscover https://autodiscover.example.com https://example.com:443 http://example.com:443
CalDAV https://cpcalendars.example.com https://example.com:2080 http://example.com:2079
CardDAV https://cpcontacts.example.com https://example.com:2080 http://example.com:2079
Web Disk https://webdisk.example.com https://example.com:2078 http://example.com:2077
Important:
We strongly recommend that you only use secure ports to access services on your server. For more information about ports on your cPanel & WHM server, read our How to Configure Your Firewall for cPanel & WHM Services documentation.

Bypass using the cPanel service SSL certificate

Warning:
We do not recommend this action.

To prevent the use of the cPanel service SSL certificate for the cpanel, whm, webdisk, and webmail subdomains:

  1. Disable the Service subdomains setting in the Domains section of WHM’s Tweak Settings interface (WHM » Home » Server Configuration » Tweak Settings).

  2. Use cPanel’s Domains interface (cPanel » Home » Domains » Domains) to create each service subdomain (for example, cpanel, whm, webdisk, and webmail).

  3. Redirect each service’s subdomain to the correct secure URL and port:

Service Subdomain Redirection
cPanel cpanel.example.com https://example.com:2083
WHM whm.example.com https://example.com:2087
Web Disk webdisk.example.com https://example.com:2078
Webmail webmail.example.com https://example.com:2096

When you navigate to webmail.example.com, the server redirects you to https://example.com:2096. Then, it uses the example.com domain’s SSL certificate to secure the connection.

Additional Documentation