Does creating a 10th level domain require creating 9 domain that preced to it?

Question

Let's say, I own a domain example.com and it's setup correctly in my domain management dashboard. Now I want to create a long subdomain of the 10th level:

d10.d9.d8....d2.example.com

Will all that require that I somehow specify the IP addresses, or whatever what's required, for all the 9 domains that preced it? Or can I go straight to d10. and specify the IP address for d10 only?

you can `c.r.e.a.t.e.s.u.b.dom.tld in a 1.2.3.4` and don't need any other than that — djdomi, Apr 14 '22 at 17:33

score 1 · Answer 1 · answered Apr 14 '22 at 17:50

1

A major misconception is that a dot in a name is necessarily a delegation. It is NOT.

Said otherwise, in the zonefile of example.com you can totally have this line:

d10.d9.d8.d7.d6.d5.d4.d3.d2.d1.d0 300 IN TXT "why not?"
d10.d9.d8.d7.d6.d5.d4.d3.d2.d1.d0 300 IN A 192.0.2.42

You can look at my longer answer for a similar question ("Do intermediate subdomains need to exist?") at https://serverfault.com/a/973788/396475 from which I am copying here only this:

TL;DR: yes intermediate subdomains need to exist, at least when queried for, per definition of the DNS; they may not exist in the zonefile though.

answered Apr 14 '22 at 17:50

Patrick Mevzek

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And this capability is heavily relied upon in reverse IPv6 zones (they wouldn't literally work without it). – Tomek Apr 14 '22 at 19:33
@Tomek Yes, this is one typical use case, described in my longer answer linked to from there, I did also add other typical cases of such "long" names. – Patrick Mevzek Apr 19 '22 at 22:08

Does creating a 10th level domain require creating 9 domain that preced to it?

1 Answers1