Hello @ANIL KUMAR DUSANAPUDI,
The best way to migrate on-premises AD to Azure while decommissioning the on-premises AD is to first establish a hybrid identity using Azure AD Connect with Password Hash Synchronization (PHS). Then, migrate your applications to Azure. If your applications require traditional domain services (Kerberos, NTLM), deploy Azure AD Domain Services (Azure AD DS) in your Azure Virtual Network and domain-join your application servers to Azure AD DS. Once all applications are successfully authenticating against Azure AD or Azure AD DS, you can decommission your on-premises domain controllers.
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