Server 2008r2 pdc server migration to 2019

Hello Silva,

Thank you for posting question on Microsoft Windows Forum.

The followings are the plausible explanation to address your queries.

1.Whether is it possible to migrate ?

• Migrating your Active Directory (AD) from Windows Server 2008 R2 (with forest functional level 2003) to Windows Server 2019 is possible. But it requires careful planning due to the legacy forest functional level and the age gap between the source and target OS versions.

2.What are the steps need to take ?

• The following steps are needed for considering to perform migration.

1. Evaluate the business requirements for Active Directory migration.
2. Perform an audit on the existing Active Directory infrastructure to verify its health.
3. Create a detailed implementation plan.
4. Prepare the physical/virtual resources for the domain controller.
5. Install Windows Server 2019 Standard/Datacenter.
6. Patch the servers with the latest Windows updates.
7. Assign a dedicated IP address to the domain controller.
8. Install the AD DS role.
9. Migrate the application and server roles from the existing domain controllers.
10. Migrate the FSMO roles to the new domain controllers.
11. Add new domain controllers to the existing monitoring system.
12. Add new domain controllers to the existing DR solution.
13. Decommission the old domain controllers (all).
14. Raise the domain and forest functional levels.
15. Perform ongoing maintenance (Group Policy review, new-feature implementations, identifying and fixing Active Directory infrastructure issues, and more)

• Please refer to the following articles for more information.
• https://techcommunity.microsoft.com/blog/itopstalkblog/step-by-step-guide-active-directory-migration-from-windows-server-2008-r2-to-win/2888117
• https://www.rebeladmin.com/active-directory-migration-from-windows-server-2008-to-2019/

3.Whether we need to raise forest function level to 2008 ?

• Please peruse below articles for any potential impact regarding raising forest functional level.
• https://learn.microsoft.com/en-us/troubleshoot/windows-server/active-directory/raise-active-directory-domain-forest-functional-levels
• https://techcommunity.microsoft.com/blog/askds/what-is-the-impact-of-upgrading-the-domain-or-forest-functional-level/399348

Also, it is paramount important to check the following points prior to proceeding the migration process.

• Verify system state backups of all domain controllers
• Check application compatibility with newer AD versions
• Document current FSMO roles (especially PDC emulator location)
• Ensure DNS is healthy (critical for AD operations)

Hope the above information is helpful!