Thomas E Dukes spake the following on 4/12/2006 4:42 AM:
-----Original Message----- From: centos-bounces@centos.org [mailto:centos-bounces@centos.org] On Behalf Of Johnny Hughes Sent: Wednesday, April 12, 2006 7:28 AM To: CentOS ML Subject: RE: [CentOS] Sendmail problem
On Wed, 2006-04-12 at 07:13 -0400, Thomas E Dukes wrote:
-----Original Message----- From: centos-bounces@centos.org [mailto:centos-bounces@centos.org] On Behalf Of Alexander Dalloz Sent: Wednesday, April 12, 2006 7:06 AM To: CentOS mailing list Subject: RE: [CentOS] Sendmail problem
Am Mi, den 12.04.2006 schrieb Thomas E Dukes um 2:23:
Here'sanother bounce email:
The original message was received at Tue, 11 Apr 2006
19:16:44 -0400
from localhost.localdomain [127.0.0.1]
----- The following addresses had permanent fatal
errors -----
xxxxxx@comcast.net (reason: 521-EHLO/HELO from sender 71.31.91.127
does not map
to localhost.localdomain in DNS)
----- Transcript of session follows ----- ... while
talking to
gateway-s.comcast.net.:
>> MAIL From:apache@localhost.localdomain SIZE=2176
<<< 521-EHLO/HELO from sender 71.31.91.127 does not map to localhost.localdomain in DNS <<< 521-sending machine
name must be
provided as a fully <<< 521-qualified domain via
EHLO/HELO command.
<<< 521-see section 4.1.1.1 and 4.1.4 of RFC 2821 <<< 521
521: Comcast
requires that all mail servers must have a PTR record
with a valid
Reverse DNS entry. Currently your mailserver does not fill that requirement. For more information, refer to: http://www.comcast.net/help/faq/index.jsp?faq=Email118405 554 5.0.0 Service unavailable
2 things:
- Your mail host at that time of the mail had the hostname
localhost.localdomain, thus your Sendmail used it for
EHLO/HELO. You
fixed that meanwhile
- The remote side requires not only a valid forward DNS record
(palmettodomains.com points to that IP) but too a
matching reverse
one. From here I can't judge whether the named IP is static and thus assigned by your ISP. If that is the case then you really should take care for both types of DNS entries. If not (you are on an dynamic line) you should use your ISP's mail host as SMART_HOST within your Sendmail configuration. DynDNS is a very bad base for reliable mail services.
Alexander
Hello Alexander,
Yes, I have a dynamic IP address. If I use my ISPs mail
host as the
SMART_HOST, would that cause relaying problems? I tried
that on the
mail client end a while back and got errors about relaying.
Thanks, I'll give it a try.
Just as a side note here ... the majority of mail servers now use a technique called Realtime Blackhole List (RBL).
Many of the new lists contain the IPs of all dynamic Cable/DSL providers as a huge amount of spam is sent via broadband PC's that have been compromised.
It is a losing proposition to use dynamic machines to send reliable e- mail as a server ... at least that has been my experience.
Hey Johnny,
Yes, I know. I have that problem sending mail to AOL (that's ironic) and RoadRunner accounts. If my ISP hadn't lost its mind for what they charge ($180/month) for a static/business DSL account, I would be on that.
Thanks!!
AOL only wants to send spam, not receive it. You will need to make arrangements to use a smart host somewhere on a fixed ip with good reverse mapping. They will need to be contacted to set your domain up as an authorized relay. You might be able to rent such service monthly, and it should be much cheaper.