We have an AD-integrated DNS environment with ~80 reverse lookup zones built up over years, all created independently with no parent zone. The 10.in-addr.arpa parent does not exist; we just have dozens of standalone x.10.in-addr.arpa zones, multiple x.172.in-addr.arpa zones, and a handful of others (100.192.10.in-addr.arpa, 168.192.in-addr.arpa, etc).
We want to create 10.in-addr.arpa as a consolidation point, then migrate the existing child zones into it one at a time and delete the old standalone zones as we go.
The core question: what does creating 10.in-addr.arpa do to the existing child zones that sit "under" it?
Specifically:
- Are existing child-zone records destroyed? The known TechNet behaviour is that creating a child zone under an existing parent can wipe records. Does the same happen in reverse, i.e. creating the parent after the children exist?
- Are auto-delegations created in the new parent pointing at the existing child zones, and how quickly?
- Do the child zones keep answering queries normally while the parent exists alongside them?
- Where does dynamic registration go for subnets with no existing child zone, once the parent exists?
DCs are a mix of Windows Server 2019 Standard (majority) and 2025 Standard. No lab/replica available to test, so I can't trial this against production blind. Documentation covering this specific "parent created after children" case would also be welcome, we've found plenty on the normal top-down order but nothing on this.