I'm planning to update our Active Directory domain name from 'costoso.com' to 'ad.contoso.com', as it's currently identical to our public domain. We have a hybrid setup with Entra and AD on-premises. I've already set up a couple of new 2022 server VMs to replace our two old 2019 domain controllers. While I've found a few guides, I'm hoping to get some recommendations on effective tools or detailed guides for this process. Since we're a small business with about 40 users, I'm also looking for any potential pitfalls or 'gotchas' to watch out for while managing this change.
2 Answers
I have to ask—what's the main reason for this change? It seems like a lot of work for minimal benefit since the internal domain name doesn’t usually impact much. What’s driving this for you?
I've successfully renamed a domain at a previous job using the official Microsoft Rendom tool. Just make sure to follow their instructions closely since there's quite a bit of prep involved. You'll need a list of all services tied to domain accounts; you'll have to update these once you change the name. Also, prep your users' UPNs ahead of time since they can be updated to the new name before finalizing the rename. Don't forget to have your DNS zone ready, and review any third-party integrations carefully. Finally, pick a day where everything can be down for at least a day, just to be safe! After the process, keep a close eye on AD replication and functionality.
We're trying to follow best practices, plus our new domain controllers are moving to a new Proxmox cluster as we're leaving VMware behind. But the more I dig into it, the more it feels like it's not really worth the hassle.