Migration to new DC with new subnet

Question

Hello,

we have a Domain, which have 2 Domaincontroller (WS2012R2) and only 1 Subnet.

we would like to migrate the Domaincontroller to a new installed Server (WS2022) but the new Server is in another Subnet.

the old DCs (WS2012R2) will be taken out of the Service.

How can we do that? How should we change the Network Konfiguration auf the Clients?

Answer 1

Hello,

This may requires some more context but high view will be :

• Promote the new server as DC
• Transfer FSMO Roles
• Demote Old DC

Firewall and NSG rules should be changed prior to promote the new server as DC to give network acess for all users and services like described in the documentation below :

https://learn.microsoft.com/en-us/troubleshoot/windows-server/identity/config-firewall-for-ad-domains-and-trusts#more-information:~:text=636%20and%203269.-,More%20information,-Note

Remember to test your backup and plan for a rollback in case of any issues during the migration process.

If this answer helped, please mark it as accepted to help others find this topic.

Regards

Answer 2

Just make sure the route allows the required ports.

https://learn.microsoft.com/en-us/troubleshoot/windows-server/identity/config-firewall-for-ad-domains-and-trusts#windows-server-2008-and-later-versions

The two prerequisites to introducing the first 2019 or 2022 domain controller are that domain functional level needs to be 2008 or higher and older sysvol FRS replication needs to have been migrated to DFSR

I'd use dcdiag / repadmin tools to verify health correcting all errors found before starting any operations. Then stand up the new 2019 or 2022, patch it fully, license it, join existing domain, add active directory domain services, promote it also making it a GC (recommended), transfer FSMO roles over (optional), transfer pdc emulator role (optional), use dcdiag / repadmin tools to again verify health, when all is good you can decommission / demote old one.

--please don't forget to upvote and Accept as answer if the reply is helpful--