There are 2 ways to add a subdomain. Either as a lightweight subdomain of a main domain, or a separate domain.
The advantage of adding as a separate domain is that it can have it’s own PHP version and SSL/TLS certificate.
Login to the control panel.
Click Domain Setup
.
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Click Add New
on right side of page.
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Enter the full domain with subdomain into Domain
. Customize the rest of the values or keep the defaults the same.
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Click Create
.
You can now manage the subdomain through the dropdown at the top of the page.