Postfix Problem [Was "Re: anybody have experience with thisoutfit?"]

[Bill Campbell]

On Tue, Jan 11, 2005, Shannon Scott wrote:
>I use pop-before-smtp.
>
>http://popbsmtp.sourceforge.net/
>
>I am curious, how do the more knowledgeable folks on the list handle
>remote relay with PostFix?  

We've been using the WHOSON daemon for this for several years now, largely
because (a) it's simple, and (b) it works with multiple mail servers.
Basically the POP/IMAP servers notify a whoson server via udp or tcp when a
user successfully logs in, and the whoson server notes the IP address as
good for some specified period of time (ten minutes by default).

The main disadvantage I see with the pop before smtp solutions I've looked
at is that they only work when the POP/IMAP server is on the same system as
the MTA (postfix here).  This doesn't cut it when running distributed mail
systems where the MTA and POP/IMAP servers are on different machines.

One thing I figured out when I patched Courier-Imap to add whoson is that
it isn't sufficient to notify the server when someone logs in, because
frequently they stay logged on beyond the whoson timeout.  I now notify the
whoson server every time an IMAP command is received on an active
connection.

...

Bill
--
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