On: Domain-cli: Search domain availability from termin...

[greyface-]

There is one odd case where asking DNS won't work accurately: if a domain is registered but has no nameservers.

[anh79 → greyface-]

Can you give some example? I have tried some registrars and if you don't provide some NS information, the default NS information is used.

I have a tool in the past https://gist.github.com/icy/b30893cecc8ec657317ba93831b0fd4a... it works fine as I experience. The tool has option `--all` to check by using both google/open dns. E.g,

  $ whoisvn google-is-good.com --all
      opendns.org:   google-is-good.com   available
        googledns:   google-is-good.com   available
  
  $ whoisvn google-is-bad.com --all
      opendns.org:    google-is-bad.com   available
        googledns:    google-is-bad.com   available

[teddyh → anh79]

Look at, for example, "nmu360.se". It is registered, but has no name servers configured.

[marcosdumay → teddyh]

Whois says it has no name server (what a weird format that of .se), but digg finds an A record with 92.242.140.20 (what seems to be a register IP).

[teddyh → marcosdumay]

Let me guess: Your ISP is injecting fake DNS responses.

[feelin_googley → teddyh]

   echo nmu360.se|exec nc -vvn 91.226.37.83 43

[anh79 → teddyh]

Very good example. Thanks a lot.

[toast0 → greyface-]

Almost always, you need to provide nameservers when you register a domain. host -t NS example.org should return something, even if the listed nameservers don't exist, don't respond for that domain, or return NXDomain.

[_jomo → greyface-]

Isn't there always an SOA record?

[teddyh → _jomo]

No. If there are no name servers, there isn’t a zone, and if there isn’t a zone, there is no SOA record.