Question
Your network contains an Active Directory forest named contoso.local.
You purchase a Microsoft 365 subscription.
You plan to move to Microsoft 365 and to implement a hybrid deployment solution for the next 12 months.
You need to prepare for the planned move to Microsoft 365.
What is the best action to perform before you implement directory synchronization? More than one answer choice may achieve the goal. Select the BEST answer.
- A. Purchase a third-party X.509 certificate.
- B. Create an external forest trust.
- C. Rename the Active Directory forest.
- D. Purchase a custom domain name. Correct
Explanation
The forest is named contoso.local, and .local is a non-routable suffix that cannot be added and verified as a domain in Microsoft 365. Users synchronized with a non-routable user principal name would be given sign-in names in the tenant's onmicrosoft.com domain instead of matching their on-premises names. Purchasing a custom, publicly routable domain name, verifying it in Microsoft 365 and adding it as a UPN suffix for the users before directory synchronization is therefore the best preparation. A third-party certificate and a forest trust are not required for directory synchronization, and renaming the forest is a disruptive operation that is unnecessary because an alternative UPN suffix achieves the same result.
