On 9/25/2012 8:56 AM, Feel Zhou wrote: > /var/log/maillog > Sep 24 08:37:50 shcx postfix/smtpd[14960]: warning: > unknown[5.39.219.175]: SASL LOGIN authentication failed: > authentication failure ... > > Hello My friend > Someone who want to guess username and passwd in my mail server > What I think is, In one minute only one or two users can use > sasl auth > How can I set main.cf <http://main.cf> in postfix to stop this > happen > Thanks for your time > tom >
Use fail2ban or similar to automatically firewall clients who make too many login failures. Postfix has no such built-in features. -- Noel Jones