-----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.
Eddie