Direct Admin offers the ability to change the main domain directly within your hosting accounts control panel.
Once logged into Direct Admin, look for the “Domain Setup” setting under the “Account Manager” section as shown below
Tick the box next to your domain name
Once selected, click on the “Rename Domain” button located on the top-right of the page
You will then be presented with a modification box where you can assign the new domain. Simply fill in the new domains details and click the “Rename” button.
Will it affect the accounts username?
No, the setting will only change the accounts main domain. Your accounts username will remain the same.
What happens to email accounts?
Email addresses present on the hosting account will be renamed with the new domain.
So if the old domain had the email address email@example.com it will simply be renamed to firstname.lastname@example.org.