[Date Prev][Date Next] [Thread Prev][Thread Next] [Date Index] [Thread Index]

Re: Problems with mail system? [Fwd: Returned mail: User unknown]



On Thu 07 Sep 2000, Craig Sanders wrote:

> On Thu, Sep 07, 2000 at 11:58:33AM +0200, Paul Slootman wrote:
> > > In any case, reverse DNS lookup is reasonable, no matter what you
> > > think of DUL.
> >
> > I have to agree with this. The previous time, the discussion was using
> > DUL to block email. This is about reverse DNS lookups failing, which
> > is a completely different this. If the reverse DBS lookup fails, you
> > either have a grossly incompetent ISP(*) or a malicious one.
> 
> i'd have to disagree with this. screwed up the DNS isn't a good reason
> for bouncing mail (because there's no particular reason to believe it's

I've seen lots of spam where the originating IP address doesn't resolve.
OTOH, I've hardly ever received legitimate mail with the same problem.

> OTOH, DUL is good because their is bugger-all legitimate reason for
> anyone to be sending direct from a dialup dynamic IP address - there are
> many cheap & reasonable alternatives to doing that.

The name is badly chosen, it should be DDUL (dynamic dial up list).
I have a dialup line, but it has a fixed IP address.

> more importantly, given that the number of die-hard DIYers with linux
> boxes who insist on delivering their mail from a dynamic IP address (and

If the alternative was a "smarthost" with an ISP that can't get its
DNS straight, I'm with the die-hard DIYers.

> wont consider any alternative for any reason) is insignificant compared
> to the number of spammers who try to do the same, there is excellent
> reason to believe that the incoming mail is probably spam.

Sounds remarkably similar to my argument above about non-resolving
IP addresses and spam.


Paul Slootman
-- 
home:       paul@wurtel.demon.nl http://www.wurtel.demon.nl/
work:       paul@murphy.nl       http://www.murphy.nl/
debian:     paul@debian.org      http://www.debian.org/
isdn4linux: paul@isdn4linux.de   http://www.isdn4linux.de/


-- 
To UNSUBSCRIBE, email to debian-devel-request@lists.debian.org
with a subject of "unsubscribe". Trouble? Contact listmaster@lists.debian.org


Reply to: