On Fri, 30 Nov 2012, Ralf Hildebrandt wrote:
* Robert Schetterer <r...@sys4.de>:
Am 30.11.2012 11:44, schrieb Tomas Macek:
I cannot apply firewall rules on 587, because our clients travel with
their notebooks and still want to send their emails through our mailserver.
use fail2ban etc for blocking dynamic, brute force attacks to
submission, normally this never matched on legal clients cause they know
their passwords and submission should used only, with password auth and
tls , if afraid for dummy users, choose low blocking time
That should be sufficient!
Fail2ban looks good, I will try it. But I'm worrying about to many filter
rules in fail2ban chain, that could lead into slowing down the whole
machine. The force attacks are often really brute and the IP's of
the clients change often also. But this could be a good way...
Tomas
