is reverse dns required? (policy question)

Mark Andrews Mark_Andrews at isc.org
Fri Dec 3 00:03:57 UTC 2004


In article <41AF5C33.4050202 at nrg4u.com> you write:
>
>You would put in a global wildcard that says no smtp sender here.  Only
>for those boxes being legitimate SMTP to outside senders you'd put in a
>more specific record as shown above.  You probably have to enter some dozen
>to one hundred servers this way.  Sure your reverse zone scripts need some
>changes but it's only two or three lines.
>
>Ideally you could tell your DNS server in the zone file this:
>
>  _send._smtp._srv.*.*.173.128.in-addr.arpa.   IN TXT   "0"
>  _send._smtp._srv.*.*.82.198.in-addr.arpa.   IN TXT   "0"
>
>being overidden by more specific information on single IP addresses.

	You obviouly do not know how wildcard work in the DNS or you
	would not have made this suggestion.  Please read RFC 1034
	and work though Section 4.3.2. Algorithm with a QNAME of
	_send._smtp._srv.1.1.173.128.in-addr.arpa.



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