eMail Sent Failure Troubleshoot Tips on Postfix

首次由測試eMail Server寄出電郵至ivanlee@sum.edu.mo及user2@debian.sum.edu.mo(user2與寄件者為同在Testing Server)只有user2收到, 查看/var/log/mail.log,發現該網域主DNS(192.168.4.1)不能把電郵指向email sever,
其後第二次則轉用ivanlee@mail.sum.edu.mo (明確用其主機名作電腦後綴)即成功找到該email server.

Failure sent log /var/log/mail.log
==============================================================================

Feb 27 19:47:50 debian postfix/smtpd[17831]: connect from localhost.localdomain[127.0.0.1] Feb 27 19:47:50 debian postfix/smtpd[17831]: 8893510A5C:
client=localhost.localdomain[127.0.0.1]
Feb 27 19:47:50 debian postfix/cleanup[17834]: 8893510A5C: message- id=<20060227114639.m16250@debian.sum.edu.mo>
Feb 27 19:47:50 debian postfix/qmgr[17767]: 8893510A5C:
from=, size=1204, nrcpt=2 (queue active) Feb 27 19:47:50 debian postfix/smtpd[17831]: disconnect from localhost.localdomain[127.0.0.1] Feb 27 19:47:50 debian postfix/smtp[17835]: connect to sum.edu.mo
[192.168.4.2]: No route to host (port 25) Feb 27 19:47:50 debian postfix/local[17836]: 8893510A5C:
to=, relay=local, delay=0, status=sent (delivered to mailbox) Feb 27 19:47:53 debian postfix/smtp[17835]: connect to sum.edu.mo
[192.168.4.1]: No route to host (port 25)
Feb 27 19:47:53 debian postfix/smtp[17835]: 8893510A5C:
to=, relay=none, delay=3, status=deferred (connect to
sum.edu.mo[192.168.4.1]: No route to host)

==============================================================================


success sent log
=============================================================================
Feb 27 19:58:35 debian postfix/smtpd[17859]: connect from localhost.localdomain[127.0.0.1] Feb 27 19:58:35 debian postfix/smtpd[17859]: B909610A62:
client=localhost.localdomain[127.0.0.1]
Feb 27 19:58:35 debian postfix/cleanup[17862]: B909610A62: message- id=<20060227115618.m87347@debian.unknown>
Feb 27 19:58:35 debian postfix/qmgr[17767]: B909610A62:
from=, size=1278, nrcpt=1 (queue active) Feb 27 19:58:35 debian postfix/smtpd[17859]: disconnect from localhost.localdomain[127.0.0.1] Feb 27 19:58:35 debian postfix/smtp[17863]: B909610A62:
to=, relay=mail.sum.edu.mo[192.168.253.78],
delay=0, status=sent (250 2.0.0 k1R3g2q15481 Message accepted for delivery) Feb 27 19:58:35 debian postfix/qmgr[17767]: B909610A62: removed =============================================================================