Re: [exim] RDNS lookup failures...

Top Page
Delete this message
Reply to this message
Author: James Price
Date:  
To: exim-users
Subject: Re: [exim] RDNS lookup failures...
My 2 cents to clarify. I want to only deny based on Mike Cardwell's #1:
1.) No reverse DNS
    - This tells me that the source probably shouldn't be sending mail,
      or has been configured incorrectly


As for the small business issue. I'm not denying based on whether the a
record matches the reverse, only if the IP has a ptr record. Most ISP's
these days from small to very large follow a standard protocol of
123-456-789-890.ip.domain.com in many cases for dynamic addresses as well as
static assignments. Further if you simply request from your ISP, most will
change the RDNS to match whatever you want.

That all being said, I just want to deny based on if there's a ptr record
for a given IP, not if it matches the a record.

Mike thanks again for a good tip.

Should I lose the host_lookup = * in the beginning of the config?

J

-----Original Message-----
From: exim-users-bounces@??? [mailto:exim-users-bounces@exim.org] On
Behalf Of Jakob Hirsch
Sent: Friday, March 09, 2007 7:25 AM
To: exim-users@???
Subject: Re: [exim] RDNS lookup failures...

Quoting Arthur Hagen:

> There's also a boatload of small, but legitimate businesses who, in
> order to save money, make do with an ADSL line and a single IP address.


Ah, this topic again... My 2c: That's fine, if it works for them. But
the should not expect all the people they want to send mail to carry
their burden (by wasting resources because of increased spam volume).
Especially with have a small business that needs every customer, you
should take reasonable care that they all get your mail. This does not
comprise acting like a spam sling (dynamic IP, no/invalid rDNS,
mismatching HELO, ...)



--
## List details at http://www.exim.org/mailman/listinfo/exim-users
## Exim details at http://www.exim.org/
## Please use the Wiki with this list - http://www.exim.org/eximwiki/