Re: [Exim] Inbound Hosts without valid rDNS

Αρχική Σελίδα
Delete this message
Reply to this message
Συντάκτης: Exim User's Mailing List
Ημερομηνία:  
Προς: Jeff Lasman
Υ/ο: Exim User's Mailing List
Αντικείμενο: Re: [Exim] Inbound Hosts without valid rDNS
[ On Tuesday, December 30, 2003 at 10:08:44 (-0800), Jeff Lasman wrote: ]
> Subject: Re: [Exim] Inbound Hosts without valid rDNS
>
> > > I am not
> > > saying that the hostname of the server has to be this same DNS
> > > name. I'm only saying:
> > > 1.2.3.4 -> blah.dom
> > > blah.dom -> 1.2.3.4
> > >
> > > and the mail server could be using mail.someotherdomain.lan with ip
> > > 1.2.3.4
>
> This is NOT broken reverse DNS.


Yes, actually, it is.

> It's reverse DNS pointing to the system
> while forward DNS is set for a domain name hosted on the system.


Which is "broken reverse DNS", almost by definition.

(though of course it's not the only way to "break" reverse DNS)

> And it's about all you can do if you've got multiple domains hosted on
> the same IP#.


Sorry, that's also completely and totally false on all fronts.

1. sane administrators don't use IP#s to host either multiple e-mail or
HTTP domains, and there's little, if any, real need to "host"
multiple domains for any other common protocol (e.g. DNS, FTP, etc.).
(SSL is about the only protocol that needs a unique IP per server,
and even the requirement for it will eventually disappear)

2. you can, as has been repeated zillions of times now, easily have
multiple hostnames for the same address and still have valid,
correct, and complete reverse DNS for that address.

--
                        Greg A. Woods


+1 416 218-0098                  VE3TCP            RoboHack <woods@???>
Planix, Inc. <woods@???>          Secrets of the Weird <woods@???>