Hello,
I have to revisit this topic now because I have changed my server to use open directory and in the process, I had to change the hostname of my server from shenzhenparty to shenzhenparty.com. Now postfix is able to detect a mail loop again.
I have found out that I should be setting up what is called a "Null Client" so that postfix delivers mail to another server and doesn't try to deliver mail to itself. I got the instructions for the null client from here:
http://www.postfix.org/STANDARDCONFIGURATION_README.html#nullclient
The problem is is that I have the EIMS mail server running on the same machine and so when postfix tries to connect to it, it still is able to detect that it is sending to the same machine and thus it refuses to connect to the other mail server as in the log below:
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May 29 14:30:21 shenzhenparty postfix/cleanup[23298]: 506E15F725C: message-id=<20060529063021.506E15F725C@shenzhenparty.com>
May 29 14:30:21 shenzhenparty postfix/qmgr[23034]: 506E15F725C: from=<info@shenzhenparty.com>, size=868, nrcpt=2 (queue active)
May 29 14:30:21 shenzhenparty postfix/error[23301]: 506E15F725C: to=<classifieds@shenzhenparty.com>, relay=none, delay=0, status=bounced (local delivery is disabled)
May 29 14:30:21 shenzhenparty postfix/smtp[23302]: warning: host mail.shenzhenparty.com[210.17.235.228] greeted me with my own hostname shenzhenparty.com
May 29 14:30:21 shenzhenparty postfix/smtp[23302]: warning: host mail.shenzhenparty.com[210.17.235.228] replied to HELO/EHLO with my own hostname shenzhenparty.com
May 29 14:30:21 shenzhenparty postfix/smtp[23302]: 506E15F725C: to=<szclassifieds@gmail.com>, relay=mail.shenzhenparty.com[210.17.235.228], delay=0, status=bounced (mail for mail.shenzhenparty.com loops back to myself)
May 29 14:30:21 shenzhenparty postfix/cleanup[23298]: 5B1C55F725E: message-id=<20060529063021.5B1C55F725E@shenzhenparty.com>
May 29 14:30:21 shenzhenparty postfix/qmgr[23034]: 5B1C55F725E: from=, size=2809, nrcpt=1 (queue active)
May 29 14:30:21 shenzhenparty postfix/qmgr[23034]: 506E15F725C: removed
May 29 14:30:21 shenzhenparty postfix/error[23305]: 5B1C55F725E: to=<info@shenzhenparty.com>, relay=none, delay=0, status=bounced (local delivery is disabled)
May 29 14:30:21 shenzhenparty postfix/qmgr[23034]: 5B1C55F725E: removed
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Postfix seems to have an option for everything, doesn't it have an option to disable this loop back check? i have looked through all the options and have not found a way. Below is my postfix configuration in case that helps:
shenzhenparty:~ deverman$ postconf -n
command_directory = /usr/sbin
config_directory = /etc/postfix
daemon_directory = /usr/libexec/postfix
debug
peerlevel = 2
html_directory = no
inet_interfaces = localhost
local_transport = error:local delivery is disabled
mail_owner = postfix
mailbox
sizelimit = 0
mailq_path = /usr/bin/mailq
manpage_directory = /usr/share/man
mydomain = shenzhenparty.com
mydomain_fallback = localhost
mynetworks_style = host
myorigin = $mydomain
newaliases_path = /usr/bin/newaliases
queue_directory = /private/var/spool/postfix
readme_directory = /usr/share/doc/postfix
relayhost = mail.shenzhenparty.com
sample_directory = /usr/share/doc/postfix/examples
sendmail_path = /usr/sbin/sendmail
setgid_group = postdrop
smtpd
tls_keyfile =
unknown
local_recipient_rejectcode = 550