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Date: Sat, 14 Jun 2003 10:13:08 -0300
From: Paulo Fragoso <paulo@nlink.com.br>
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Subject: Limit for smtp connection
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Hi,

How can we limit the number of simultaneously accepted
connections from the same IP address to our smtp server?

We are using qmail+daemontools+spamcontrol+qmailscanner+spamd, but 
sometimes there are floods from same IP to our server (smtp port), 
reaching connetions limit configured on tcpserver startup (tcpserver -c 
#). We can't increase this limit because it can kill other process by 
out swap (DoS).

We have found some SMTP server on the internet which accept no more than 
5 simultaneusly connection from our SMTP server. How to implement this 
using qmail+tcpserver?

Paulo.