A weird one that we came across today, around how InfoBlox handles a record in a parent zone which is named in such a way that it falls within scope of a subzone, then you later “cut” the zone by formally creating the subzone (i.e. delegating); in our case these records just disappear. i.e. they don’t get moved automatically to the subzone.
Essentially I have a record called portal.sub.domain.com within the domain.com parent zone. Notice that the record name is portal.sub which is/are subzones of domain.com. If you then later “cut” the zone, so create a subzone called sub.domain.com, so this record name falls into scope of the subzone, records named as *.sub.domain.com.
I trawled through the documentation and haven’t yet found this stated in the documentation, but this is what I did find, maybe it is of help to someone.
I’ve not found anywhere (yet), where it is explicitly stated that records are (silently deleted) when they that are named in the form of a subzone (e.g. portal.sub.domain.com), thus falling within scope of a sub-zone; and then you later formally create (delegate) said sub-zone.
However, it would seem logical that they would be disappeared, when you “cut” the zone, depending on if/how you infer from it, the documentation says:
“You create an authoritative zone when you assign authority for all the resource records of a particular domain to one or more name servers.”
https://docs.infoblox.com/space/nios90/280763230/Adding+an+Authoritative+Subzone
At which point the parent is no longer authoritative for that part of the name space, so it would be logical that they are not longer able to exist in the parent zone. But nothing specifically about them being removed.
But it does talk about it working the other way round, but in that case the records ARE preserved when they are “reparented”. https://docs.infoblox.com/space/NAG8/22251670/Removing+Zones
But, https://www.rfc-editor.org/rfc/rfc2181 RFC 2181 talks about “zone cut(s)” where it basically says (obviously) you can’t have a delegated subzone and a parent zone both with records for the delegated subzone. So I guess if they are following the RFC, they would indeed just disappear.
So I guess it is one of those things just to be aware of at the point of subzoning a parent zone where there exists records that fall within scope of the subzone.