Re: [DNSOP] Status of "let localhost be localhost"?

George Michaelson <> Wed, 02 August 2017 22:55 UTC

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From: George Michaelson <>
Date: Thu, 3 Aug 2017 08:55:41 +1000
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Subject: Re: [DNSOP] Status of "let localhost be localhost"?
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A possibly stupid random thought: is there a strong barrier in *all*
kernels which enforces and ::1 to actually *have* to be

The 240/4 problem is 5-6 lines of code in *some* UNIX. It wasn't in
any sense globally applied.

I suspect localhost is somewhat more strongly coded, but I did wonder
because Ted's suggestion that use of the literal IP address in either
family would the stronger 'keep it local' made me think: what if
somebody hand installed a route which somehow took it off-box?

I think proscriptive/definitive language over the FQDN/label localhost
in DNSSEC is probably still a good thing.  IETF is defining behaviours
for in HOMENET which logistically fall into a very similar
bucket (for me at least) so its not like we can't chose to say what
behaviours we expect of a label.