So several years ago I saw a DNS service which you could for example put something like:
192.168.1.2.<something>.io and it would return an A record for 192.168.1.2.
You could put any IP address as the subdomain and it would return the A Record for that IP address.
This was useful for testing website configuration on a private network when you couldn't edit the company DNS records.
Sadly I cannot remember the name of the site. I think it was a
.io domain, but that is all I remember.
Does anyone know the name of this service, or a tool that could do this?