Re: [exim] why so many synchronisation failures?

Am 30.04.2018 um 13:51 schrieb John via Exim-users:
> I am seeing a large number of synchronisation errors in incoming mail
> eg
> rejected connection from H=[198.53.60.171] input="QUIT\r\n"
>
> The IP address varies but the QUIT\r\n is the commonest version, and
> overwhelmingly from places with no reverse DNS.
> I am sure this is unwanted stuff, but what are the malefactors trying
> to achieve?
>
>
> =John ffitch
>
That comes from very poorly written Fire-And-Forget-SPAMscripts.

They are sending the commands by a script and don't react to responses,
like a real mailserver would do.
So they miss the point, when your exim tells them, that they did
something wrong. They keep sending
the cmmand at position n+1 as nothing wrong had happend.

Make a script, filter those lines, make a firewall entry and block them
for 48h hours.

best regards,
Marius