Wildcard subdomains allow you to point all the subdomains ( existing and non-existing ) to a specific folder in your account. It means that if you enter any subdomain in your browser ( for example, test.domain.com – not existing, or blog.domain.com – existing), it will show the same content that you uploaded to the folder for the wildcard subdomain.
In order to create a wildcard subdomain, please, follow the next steps:
1) Log in your cPanel
2) Navigate to the menu ‘Subdomains’ under ‘Domains’ section
3) Create a subdomain‘*’ pointing it to the necessary folder ( you will need to specify the path in the field ‘Document Root’ ).
4) Go to the menu ‘Advanced DNS Zone Editor’
5) Make sure that there is an A record for *.yourdomain.com created and pointed to the server IP address ( it could coincide with the IP address of your main domain or ftp.yourdomain.com is pointed to).
6) Now you will need to wait until the propagation is over ( it should take N seconds, where N – is TTL for this A record; you can edit it manually and reduce the number to speed up the process ) and then the wildcard subdomain will work correctly.