There must be something useful here…

In today’s match we have a Qmail Server that has been demoted from sending and receiving email to just sending. The server had been properly configured for the new changes and email was successfully being sent off the server. Today, however mail stop sending to only one domain, the old domain that was hosted on the server.

The first place to look is the logs. Read the logs, know the logs, they will help you. Here is a command that will take the non-human readable date code and make it readable for better understanding:
cat /var/log/qmail/qmail-send/current |tai64nlocal |less

There are 2 major logs to check when dealing with qmail:
/var/log/qmail/qmail-smtp/current
/var/log/qmail/qmail-send/current

Here is a sample of a bounce message log entry:

2010-10-08 11:04:05.068209500 starting delivery 280: msg 1328309 to local dump@maul.com
2010-10-08 11:04:05.075688500 status: local 1/10 remote 0/120
2010-10-08 11:04:05.141754500 delivery 280: failure: Sorry,_no_mailbox_here_by_tha
t_name._(#5.1.1)/
2010-10-08 11:04:05.146678500 status: local 0/10 remote 0/120
2010-10-08 11:04:05.155633500 triple bounce: discarding bounce/1328309
2010-10-08 11:04:05.158451500 end msg 1328309
2010-10-08 11:08:06.159425500 new msg 1327108
2010-10-08 11:08:06.159435500 info msg 1327108: bytes 1025 from qp 5008 uid 0

The important thing to follow here is the “delivery 280.” That is the delivery number that will allow you to follow the message. In this case we can see it was a local delivery that failed and now is bouncing.

It can be daunting to dig through the log files, but they will have the answer if you look.

Cheers,

Mike