Merge Non-PROD with PROD tenant

robcool 116 Reputation points


We are performing a merge of non-prod tenant to PROD tenant. This is minimise the effort involved in maintaining two Azure AD tenants.

As part of this process, the custom domain in non-prod tenant can't be added to PROD tenant as there can't be same domain in two different Azure environments. Please let me know how can this issue be tackled as we need to move the identities from one tenant to another while ensuring the access to workloads in non-prod tenant remains as is until the final cutover ?


Microsoft Entra
Microsoft Entra ID
Microsoft Entra ID
A Microsoft Entra identity service that provides identity management and access control capabilities. Replaces Azure Active Directory.
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  1. AmanpreetSingh-MSFT 56,506 Reputation points

    Hi @robcool • Thank you for reaching out.

    If you are synchronizing identities from the Local AD forest to the Non-prod Azure AD tenant, you can sync those identities to the Prod tenant using AD Connect. As Azure AD Connect supports Multiple forests, single Azure AD tenant scenario, you will get the Non-prod users synced to the prod tenant but they will be synced with UPN suffix. At this point, you will have all users in the prod tenant and the Non-prod tenant will also have the existing synced users that can be used to access to workloads in that tenant.

    During the final cutover, you will have to remove/update all the entities that are using the custom domain in the non-prod tenant so that the custom domain can be removed from the non-prod tenant and added to the prod tenant. Once the custom domain is moved, all you need to do is to flip the UPN suffix of the non-prod users in the prod tenant from to using the Set-MsolUserPrincipalName cmdlet.

    If you are using cloud-only users and not synced users, you will have to provision the users in bulk to the prod tenant by either using PowerShell Script or Graph batching. Below is the PowerShell Script for your reference:



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