[miles]

Back in 2000, there was an IETF Internet-Draft entitled DNS Top Level Domain For Private Networks[0] that recommended using .pri:

"A reserved top level domain name, '.pri', would allow a private domain name to be chosen safely with no risk of conflict with current or future registered domain names. A private DNS server is configured as authoritative for the '.pri' domain, and delegates the private subdomains as appropriate."

It sadly was never picked up[1].

Over the years, Microsoft has recommended and in some instances even forced[2] the use of .local, which they now advise against[3].

[0] http://tools.ietf.org/html/draft-coffeystrain-privatednstld-...

[1] https://datatracker.ietf.org/doc/draft-coffeystrain-privated...

[2] https://www.microsoftpressstore.com/articles/article.aspx?p=...

[3] http://technet.microsoft.com/en-us/library/cc738121%28WS.10%...

[WorldMaker]

Though the interesting answer to why Microsoft now has to advise against .local is that RFC 6762 reserved it as a special-case for Multicast DNS (mDNS fka Bonjour and a bunch of other names).

https://en.wikipedia.org/wiki/.local

[JdeBP]

.local actually has two conflicts.

* http://jdebp.eu./FGA/dns-use-domain-names-that-you-own.html