On Mon, Feb 19, 2018 at 08:48:10PM +0000, Brian wrote: > > .invalid should fit the bill. You don't get much help on this from the > installer in expert mode though. My point was - how do you know what is > non-existent? knickersoff.com was a revelation to me! > It is all documented: https://en.wikipedia.org/wiki/Top-level_domain#Reserved_domains
Essentially, you cannot guarantee that any arbirtary second-level or lower domain will remain unused. However, there are reserved top-level domains guaranteed to not be used in any standards-compliant implementation and you can also be somewhat certain that new top-level domains will not be introduced willy-nilly. So, if you wanted to use .abc123 as a top-level domain on your own network, you are probably safe. Regards, -Roberto -- Roberto C. Sánchez
