I'm trying to find the list of all whois servers for COM/NET. Verisign is the authoritative registry for the .com, .net, .name, .cc and .tv domains.
Possible solution: To find out the complete list of whois servers is to crawl through at least a million of them (via whois.crsnic.net) using the domain list from the .com zone file and read the official whois from the whois result.
That way I could probably build a 90%+ complete list. I'm ready to go that route and post a result here but if anybody knows a better way/source, please do help. Thank you!
Unfortunately, there is no definitive list. You may try to contact Verisign and ask them if they can extract a list of all accredited registrars.
The other possibility is to use a crawler, but as you noticed is not as accurate.
I found all the accredited registrars on Verisign website, crawled their whois with each company name and got the whois server.
Here's a list of all the whois servers for .com and .net in PHP array:
Made for my startup company WhoAPI.com.
If anyone still reads this: As long as Verisign is a 'thin' registry, there will never be a list of whois servers. At least not a reliable one.
Verisign accredits registrars on a daily basis, and each registrar has a whois server of their own. Also, a registrar may decide to change the hostname of their whois server.
You have to make this a two-step process. First, check whois.internic.net for who is in charge of the domain, then query the registrar's whois. Registrars can get that information through the Verisign API (i.e. an extension of the EPP protocol)
I am not even sure what the list could be used for. You certainly do not want to query 1500+ whois servers trying to find the registrar in charge of a given domain