dictionary attack

[Steve Freegard]

On 19/02/11 06:50, Ejaz wrote:
> All,
>
> Yes it’s true we are accepting emails from anywhere and anyone there is
> no recipient table exist on the server (function of this server is to
> filter incoming mails ) and then redirecting them as per the transport file
>

See 
http://wiki.mailscanner.info/doku.php?id=documentation:configuration:mta:postfix:how_to:reject_non_existent_users#using_smtp_recipient_verification

Or - if the destination can't reject invalid users at SMTP time; then 
you'll need to build a recipient table to reject the invalid ones 
(covered on the same page).

Regards,
Steve.