Comment by ndriscoll
16 days ago
Haven't they been telling people to do that since before it became reserved? If so, the problem is more that you can't "reserve" something that's already in wide use, and mdns should've used something like .mdns.
It's like when .dev became a gTLD, knowingly breaking a bunch of setups for a mix of vanity and a cash grab. Obviously dropped the ball on the engineering side.
Seems more a reason to never use stuff you don't actually control and are reserved for future purposes. Everyone knew who was in charge of DNS TLDs and that while they were being at first conservative in how many they assigned, they reserved the right to assign as many as they wanted.
But also, yes Microsoft documentation used .local before mDNS reserved it, and IIRC Microsoft was also involved in suggesting it for mDNS as mDNS came out of the multi-company standardization efforts from Apple's Bonjour. That said, my impression of most of that documentation from that time is that it was incorrectly using .local as a fake TLD where they should have been using .example or .example.com and also pointing people to the RFCs that those were not valid choices in a real setup. A problem with such documentation is that it is too easy to take literally. A follow up problem was sort of the "accidental security through obscurity" benefits of using non-globally resolvable addresses becomes "best practice" through essentially stubbornness and status quo (related to all the recent rediscussions on HN about NAT44 is not a firewall except by accident and you can have very good firewalls that aren't NAT44).
> my impression of most of that documentation from that time is that it was incorrectly using .local as a fake TLD
When setting up Active Directory on Windows Server 2003, there was a note in the wizard that explicitly called out .local as a domain suffix that would prevent DNS lookups from hitting the public internet, which many people (myself included) took as an endorsement.
I feel like I remember this in 2008 as well. I could certainly be misremembering.
> Haven't they been telling people to do that since before it became reserved
If you actually try to find an evidence for this (even time traveling to 2015 before the great wipe of most pre-Vista docs) you wouldn't find a confirmation for this. What you would find is what the official docs always recommended the root domain to be an official bought one on the public internet. And this excludes .local.