Paul Schmehl ha scritto:
I manage some server DNS and server mail and can say that reverse DNS serves why many many MTA refuse the mail from the IP without the reverse.Is there an RFC *requirement* for reverse dns?
I've been looking through the RFCs and I can't find it. Some folks think reverse dns should be completely disabled. I know for sure that this will break email, because many mail servers won't talk to a server that doesn't reverse. Tcpdump also doesn't like hosts that won't reverse.
What I'm looking for is a standard (RFC) that states that enabling reverse lookups is *required* or reverse lookups are *optional*. If they're optional, then reverse could be disabled for most hosts.
I'm also looking for a list of things that *break* when you disable reverse (e.g. mail).
RULES FOR RESPONDING:
1) "Reverse is a good thing" is not an answer. Neither is "Reverse is a bad thing".
2) Opinions are not useful - stick to facts only - chapter and verse please.
3) All replies to the list please - others will find this useful as well.
Paul Schmehl ([EMAIL PROTECTED]) Adjunct Information Security Officer The University of Texas at Dallas AVIEN Founding Member http://www.utdallas.edu _______________________________________________ Full-Disclosure - We believe in it. Charter: http://lists.grok.org.uk/full-disclosure-charter.html Hosted and sponsored by Secunia - http://www.secunia.com/
But it is also true that not is, than I know, nothing of defined in such sense.
Many ISP deny the possibility to the customer of having the reverse, others make to pay the "custom" RDNS for a domain name.
If you want to send mail to me and you do not have reverse however he does not arrive to me, perhaps...
then you make :)
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