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Re: More sorbs blacklisting

On Tue, Jun 06, 2006 at 07:46:40PM +0200, Andrew Miehs wrote:
> Kurt Petersen wrote:
> >My IP number is
> >The reverse is
> >
> >There is no indication of a dynamic IP number - and it is not. It has
> >been fixed for many years.

sorry, that's wrong - a generic PTR record including strings like
'adsl', 'ppp', 'dyn', etc IS an indication of a dynamic IP address. it
may not always be accurate but it is a very good indicator.

> @bert:~$ telnet 25
> Trying
> Connected to
> Escape character is '^]'.
> 220 ache.dk ESMTP Postfix
> Maybe you should rename your machine to

that's ugly and not necessary.

> Or get the dns fixed.

yes, get the reverse DNS fixed if you can.  it is only a few seconds work for
your ISP to fix it (but, unfortunately, that is no guarantee that they
actually will...still, they wont do it if you don't ask them to).

Kurt should also get them to report it to SORBS DUL as a static IP, not
dynamic.  IIRC, only the netblock owner can report their addresses as
static (so that spammers don't just send in an email lying about it).

also, the MX record needs to be fixed.  MX records can not point
to CNAME records, they can only point to A records. behaviour is
unpredictable, depending on how the sending server handles this - it may
work or it may not but it's unreliable and specifically documented as
NOT working.

$ mx ache.dk
ache.dk             	MX	10 mail.ache.dk
 !!! ache.dk MX host mail.ache.dk is not canonical

$ host mail.ache.dk
mail.ache.dk        	CNAME	ache.dk
ache.dk             	A

that should be:

mail.ache.dk        	A

> I personally do not believe that anything behind a dialup connection
> should be used as a 'mail server' pointed to by MX records...

me too.


craig sanders <cas@taz.net.au>           (part time cyborg)

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