What is the limit of queries on whois servers?

whois.verisign-grs.com and whois.crsnic.net points to the same WHOIS interface.

Here's the result of a dig query request.

whois.crsnic.net.   1   IN  A

whois.verisign-grs.com. 1   IN  A

According to the IANA database, the authoritative URL is whois.verisign-grs.com. However, I confirm the old one is still working.

Changing the URL doesn't give you more flexibility against request limits as they point to the same interface.

Verisign doesn't disclose the WHOIS limit.

Dear ...,

Thank you for contacting VeriSign.

We apologize but we are not allowed to disclose internal information. You will be notified once your IP is blocked from our Whois database.

Please know that your inquiry is important to us, and we value your business.

On some forums you can read it was around 1000 requests per day.