Hello @JM Wee ,
Thanks for reaching out.
Azure Active Directory Domain Services (Azure AD DS) provides managed domain services such as domain join, group policy, lightweight directory access protocol (LDAP), and Kerberos / NTLM authentication. Azure AD DS integrates with your existing Azure AD tenant, which makes it possible for users to sign in using their existing credentials.
I would recommend that you review these typical use-cases and scenarios for Azure Active Directory Domain Services to ensure that none of them are applicable to your environment.
However, based on the information you provided above, it appears that none of the Azure resources are in use, therefore you may safely delete it. Here's a step-by-step guide on how to remove Azure AD DS.
Azure AD Domain Services simply syncs with what is manages through the Microsoft 365 portal. A managed domain is configured to perform a one-way synchronization from Azure AD/M365 to Azure AD DS which provide access to a central set of users, groups, and credentials. Therefore, if you encounter any problems after deletion, you can easily rebuild Azure AD DS, which will synchronize from Azure AD.
Hope this helps.
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