> In a pathological case, qmail can use a lot more network bandwidth
> because of the duplication of messages going to the same system. In
> practice this is rarely a serious problem. Taking into account the
> *decreased* DNS traffic, it's even more rarely a problem.
It depends heavily on the usage pattern of your mailserver. Generally
qmails way is the best for normal mail traffic. It's also true if you have
enough bandwith to gain faster delivery.
But there are other scenarios too. One has to think about them if it comes
to the decision which MTA to use.
I have several customers that create the "pathological case" every day and
every hour:
- small bandwith, expensive line too
- no idea about delivery lists at the receiving site
- no idea about the purpose of SMTP, never heard about FTP
- not willing to be educated
- exchange of LAAARGE files (50MB) through mail
- typically delivery to several receivers at the same destination host
For these cases qmail is a really bad choice - I agree that this is not
the typical setup most of you are familiar with, but IT IS REALITY in many
cases. Often DNS doesn't matter because all deliveries go through a
smarthost (that of course doesn't support any of qmail's features).
It's amazing how qmail haters (here in Germany) always reduced the
discussion about qmail to this special case - it may be bad discussion
style but I also think that there is more need to support this type of
setup than the "normal" qmail administrator may assume.
Regards, Frank
