[Mailman-Developers] Re: way to minimize IO load with MTA supported VERP

[John W Baxter]

At 14:18 -0500 12/7/2001, Bob Puff@NLE wrote:
>Speaking of Exim.. one thing that really bothers me about Exim is the
>message(s) it sends when it has to wait to deliver the message... these
>would be interpreted as bounces, although they really are not.  I've seen
>a few such messages, only to have the message delivered normally.  That
>would trigger some bounce logic to at least pick up on what really isn't
>(yet) a bounce.

Exim's delayed delivery warnings are "orderly" enough that it would be
quite easy to ignore them in bounce processing.  In several ways, they
don't look like failure messages.

Meanwhile, they let a user who has mistyped an address know about it sooner
than without the messages.  For an Exim running in support of "live" users.

Assuming, of course, that the Exim administrator has resisted the
temptation to "improve" the delayed delivery message.  If she's done that,
users are likely to fall off lists.  One hopes that the Exim admin and the
Mailman admin are speaking to each other.

If the Exim is running just to handle Mailman, the warning message can be
done away with entirely (and the retry intervals can be adjusted, and
several other such adjustments made).  Trivially.  But of course, you can't
configure away messages generated by remote sites you don't control.

  --John