Configuring a custom domain
After configuring the most relevant feature sets of your Azure AD tenant. We will prepare a registered domain name to set the configuration to a productive environment.
Note
This step is optional, because you need to register an official domain at a registrar in your country.
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Click ADD A CUSTOM DOMAIN and see the verification options; note that you are the owner of the domain.
Add a TXT entry to your DNS zone to verify the domain.
Click the Verify button on your Azure portal.
After a successful verification the new DOMAIN NAME will appear under DOMAINS.