IPv4-Mapped IPv6 Address used in DNS with AAAA-records

[Thomas Schäfer]

Ondřej Caletka

(https://mastodon.social/@Oskar456/110807321268094472 )

was so nice to provide a test setup.


So I've set up some testing DNS records. The results are a bit 
surprising. Try it yourself:

https://ipv4-mapped.0skar.cz/ (AAAA with IPv4-mapped, should not be 
reachable from anywhere)
https://ipv4-mapped-pref.0skar.cz/ (dual stack A plus AAAA with IPv4-mapped)


Despite it works in most dual stack environments and most 
ipv6-mostly/only environments, it breaks when nat64 without clat is used.

Thomas


-- 

There’s no place like ::1

Thomas Schäfer (Systemverwaltung)
Ludwig-Maximilians-Universität
Centrum für Informations- und Sprachverarbeitung
Oettingenstraße 67 Raum C109
80538 München ☎ +49/89/2180-9706  ℻ +49/89/2180-9701