I've seen a US based ISP do its internal management network reverse DNS using '.us' as a suffix, where the hierarchy is like POP name, then city/airport code, then state (eg: CA, NJ, FL), then .us for geographical location of equipment in USA.

The .us domain in question was owned by the same organization but with only a stub zone file published on public facing authoritatiev NS, with the internal zonefile not available to the public. 


On Mon, Nov 6, 2023 at 7:35 AM Jay R. Ashworth <jra@baylink.com> wrote:
----- Original Message -----
> From: "Seth Mattinen via NANOG" <nanog@nanog.org>

> On 11/2/23 1:30 PM, goemon--- via NANOG wrote:
>> Are there any legitimate services running solely on .us domain names?
>
> Yes.

Though not -- by several orders of magnitude -- nearly as many as there should
be... but let's not get me started on that.

Cheers,
-- jr 'RFC1480' a
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