1: I was able to register successfully with “desec.io”.
2: I was also able to enter the ns of “desec.io” at my registry.
3: I then also created NS entries at desec.io and entered the host name (NSServer) of my storage provider.
Now, however, when I enter my created NS " ns1.domainname.com" at my registry for another domain, I receive an error message “An unexpected error occurred”.
I’m not sure I understand what you are trying to tell us here?
I understood that you have a domain (domainname.com) that is set up to use deSEC name servers, correct?
Then you created ns1 and ns2 NS records in this domain like this?
ns1.domainame.com NS ns1.desec.io.
ns2.domainame.com NS ns2.desec.org.
And then you tried to use these NS records as authoritative NS for another domain? Presumably a domain for which no zone exists at deSEC?
If this is what you did, then that is not going to work. If not please explain in more detail what you did.
I can’t see what you are actually trying to achieve. Please explain what your goal is.
Some general notes on how DNS works:
The parent zone for a domain name contains the NS glue records. E.g. for the domain domainname.com. these NS glue records would be in the zone for the com. domain. The NS glue records need to resolve to the IPs for the authoritative name servers for the domain. These name servers need to actually answer queries for the domain, i.e. they need a zone (file or database) containing the DNS records.
At least 2 authoritative NS are required and they need to be in separate networks. (So you can’t just add 2 NS records that resolve to the same IP.)
NS records point to a hostname. That hostname must resolve to one or more IPs using A/AAAA records.
HTH
fiwswe
PS. I don’t think AXFR has any bearing on this issue. But maybe I am misunderstanding what @silhub is trying to do?