Select the correct parent domain and confirm your plan permits another subdomain. Decide the document root and whether it will contain a separate application. Avoid reusing a directory that holds unrelated production files.

1. Open Account Manager > Subdomain Management for the intended domain.
2. Choose Add Subdomain and enter the requested name, such as blog, in the format expected by the form.
3. Review the resulting hostname and document root. Use the location displayed by your installation rather than assuming every server uses the same directory layout.
4. Create the subdomain and upload a harmless test page to its document root. If authoritative DNS is external, add the corresponding record at that provider using the assigned hosting address.
5. Issue or enable an appropriate TLS certificate, then install or configure the application for the new HTTPS URL. Keep application credentials and database settings separate where appropriate.

Before installing the application, create subdomain-check.html in the document root displayed for blog.example.com. Use your own hostname in the browser:

<!doctype html>
<html lang="en">
<meta charset="utf-8">
<title>Subdomain check</title>
<p>The new subdomain document root is working.</p>
</html>

Visit https://blog.example.com/subdomain-check.html. The matching sentence and a valid certificate confirm this request reached the intended file. A default page or 404 calls for a DNS and document-root check, not uploading over the parent website. Delete the probe after verification.

Visit the full hostname over HTTPS and confirm the intended test page or application appears. Verify the parent site still works and that the subdomain certificate matches. Test a login or form if it is a dynamic application.

If a default page appears, compare DNS, domain selection and document root. If creation fails, check a conflicting existing hostname or plan limit. Do not upload the new application over the parent website just because the expected directory is unclear; ask support to confirm the configured path.

• Removing a subdomain in DirectAdmin while controlling file deletion
• Creating a website or path redirect in DirectAdmin
• Creating a MySQL or MariaDB database in DirectAdmin
• Creating a restricted FTP account in DirectAdmin

• DirectAdmin Evolution: Subdomains