you'll see roundrobin and lifo, among others, in many caches including
Large numbers of sites have been depending on this behaviour for over 15
years, so it was wrong of RFC 3484 to break it.
some number of vendors have depended on revenue from selling this feature
but i'd say that only a small number of sites ever saw any benefit from it.
we've been lifo'ing and round robin'ing dns data in caches and stubs for a
lot longer than 15 years, and the original dns rfc's said specifically that
rrset ordering was not guaranteed in the protocol, so anyone who depended
on it was getting screwed a long time before RFC 3484 came around.
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