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

[ryannevius]

Why not just...

    whois example.com

Or is this also intended to be a domain discovery tool?

[arca_vorago → ryannevius]

In which case why not 'dig' or 'nslookup' too?

[greyface- → arca_vorago]

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.

[anh79 → ryannevius]

whois may not work if you don't have correct configuration (e.g, whois server for some special domains .info, .social, ...)

[teddyh → anh79]

Use a proper whois command which has all this configured. Note: may be difficult to achieve on macOS.

[anh79 → teddyh]

It's even hard on Linux machine. How do you know all whois servers for different top level domains? for .info, for .social, for .in, bla bla. In 2016 it's so painful to set up correct whois monitoring at my company . (May be it's a lot better now.)

[teddyh → anh79]

apt install whois