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[IPv6]Re: Why not add loopback semantics to 2001:db8::/32?

Michael Richardson <mcr+ietf@sandelman.ca> Tue, 02 December 2025 17:54 UTC

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From: Michael Richardson <mcr+ietf@sandelman.ca>
To: Mark Smith <markzzzsmith@gmail.com>, 6man WG <ipv6@ietf.org>, v6ops list <v6ops@ietf.org>
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Subject: [IPv6]Re: Why not add loopback semantics to 2001:db8::/32?
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Mark Smith <markzzzsmith@gmail.com> wrote:
    > If a /96 ended up being the choice, then I've thought I'd use
    > 2001:db8::/32 for any host-local loopback testing, since it too would
    > satisfy the scenarios that 1::/32 would.

No, that would be confusing.

A useful sanity check on junior administrators is that they didn't use
2001:db8: anywhere.

If they did it means that they didn't understand the example.
(or their LLM didn't)
If we use it here, then we'll have an exception to that rule.


--
Michael Richardson <mcr+IETF@sandelman.ca>   . o O ( IPv6 IøT consulting )
           Sandelman Software Works Inc, Ottawa and Worldwide

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