Kurt A. Schumacher wrote:
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This is a silly reverse setup. A reverse lookup should only return one hostname, not 20.
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Well, tend to agree.
What about the most stupid wanabe Spam-fighter which are very unhappy as in place (e.g. the third-party service provider systems acting with some SC subsidiaries...) which high rate valid messages if certain brain-dead conditions like PTR not matching MX don't match?
Trying to work around them with a dodgy DNS setup is not the right course of action, IMHO.
If this approach works out, it could be considered. It is not illegal.
Correct - it's just silly and it doesn't work as expected.
1) a properly working resolver library will return multiple records rotated once for every lookup, so you're never guaranteed to get the same answer to a reverse lookup. 2) most applications, e.g. mail-servers, that do reverse lookups do not expect more than one reply, and will always only process the first one.
It's just against what we are used to over the last 20+ years.
Plus it doesn't work.
/Per Jessen, Herrliberg