Mike Lyon wrote:
Howdy,
I know this isn't an exim related question but it's affecting the ability
for my exim install to deliver email... Anyways, It appears when my exim
install tries to deliver email to Google or Yahoo, both of them refuse the
port 25 connection from my host. I went to another server I have in a
different subnet and was able to telnet to port 25 at both Google and
Yahoo. So it appears they are blocking this one subnet I have from
connecting to them.
How does one resolve this issue?
Thank You,
Mike
'Stock' answer is to investigate the subnet with a 'whois' and see how
it is allocated. If 'AP' - as most 'residential' connectivity pools, and
all-too many so-called 'business' broadband are, then check also RBL's
such as SORBS and the like that target dynamic-IP block ranges.
These are sometimes 'discovered' and other times voluntarily listed by
ISP who have a ToS that prohibits running MTA etc - then operate an MTA
on a different block for use of their connectivity pool subscribers.
Hard to get around that. Potentially harder yet if it is a
Google-specific LBL. Several majors, such as the former 'Baby bell' in
the US, are doing that now on perfectly good IP blocks, sometimes purely
on a basis of GeoIp or host country of the block holder.
I'm presuming, of course, that with your experience level, you already
have a valid non-generic, FQDN-relevant, PTR RR and matching MX DNS
entries. Absent that, a BL needn't be checked, as a vanilla reverse
lookup fails.
Bill
--
韓家標
--
## List details at https://lists.exim.org/mailman/listinfo/exim-users
## Exim details at http://www.exim.org/
## Please use the Wiki with this list - http://wiki.exim.org/
