Re: [exim] controlling amount of messages received and relay…

Chump Chumpster wrote:
> Hi,
>
> I've been playing with maybe too many variables tweaking my Exim install and
> could probably do with getting back to basics, if someone could help out.
>
> Here's a scenario that is close to what my actual infrastructure is, but
> with round figures to keep it clear.
>
> Let's say my Exim MTA is relaying email to the public Internet for 500
> clients on a private IP LAN.
>
> Therefore on the trusted 'receive' side of the MTA, picking up email to
> relay, I'd like to able to have a large number of clients make connections
> from their mail software to be able to send email. I'd also like them to be
> able to send the same email up to 150 people in their address book at the
> same time (as one transaction).
>
> Once the MTA has got this transaction. I'd like it to relay the email, but
> in a more politically correct way for the public Internet... eg.

taking these individually:

>.. a max of 20 connections to an ISP

Possibly problematic -

20 to the same server, or even 'pool' of servers, from one origination IP may
make you look like a spam engine / Qmail.

5 or 10 is likely to be the max. Not that it matters, but ours accept as ew as
1, never more than 3. OTOH - no foul, no grey/black listing - just 'defer' util
you have fnally completed 'em.

> and no more than 50 of the same email at a time.
>

You should be good up to 100 for most correspondents, as the RFC recommends that
as a minimum.

Those among us doing per-recipient in-session DATA phase qualifying defer second
and subsequent - but that is a nearly invisible minority, safe to ignore.

> I wonder if anyone can give me any pointers in the right direction. I'm not
> sure if the params I'm using will also expose the public side of the MTA to
> being swamped by other relays coming in from the 'net.
>
> thanks for any advice....

They should not.

You may want to use a conditional tied to interface_port so as to keep in any
'special' rules or routers that