Re: Drop connection when tcpserver -c limit is reached, Is it posible?

Hi friends,

I've already fixed this problem. My solution:

Modify the tcpserver limits patch (http://qmail.jms1.net/ucspi-tcp/)  
for add a "global limit" instead of only a "per IP" and "per C-Class  
block" limit, recompile tcpserver.c and use the new binary of tcpserver.


Regards,
Spamis


Jimmy Spam <[email protected]> escribió:

>
> Hi friends,
>
> I know how limit the total concurrent connections that tcpserver can  
> handle, but, Is it posible change its behavior to drop connection  
> suddenly, instead of defer acceptance?
>
> --------------------------------------------------------------------------------------------------------------
> tcpserver:
>
> -c n: Do not handle more than n simultaneous connections. If there  
> are n simultaneous copies of prog running, defer acceptance of a new  
> connection until one copy finishes. n must be a positive integer.  
> Default: 40.
> --------------------------------------------------------------------------------------------------------------
>
> When my server receive too many connections, if tcpserver limit is  
> reached, the new incoming connections are keep in SYN_RECV status,  
> increasing permanently until my MX is KO.
>
> I've notice that my old MX, with Kaspersky MailGateway, send a  
> message: "421 4.3.1 mailhost.chg ESMTP Service not available,  
> closing transmission channel", when too many connections arrive and  
> with this action, keep the server up all time (only the smtp service  
> it's down during few seconds/minutes per day).
>
> I've thought that maybe it's a good idea send a "421 message" when  
> tcpserver -c limit is reached, in combination with SMTP550DISCONNECT  
> variable of qmail-ldap for keep the incoming concurrent connections  
> and qmail-smtdp process at correct levels.
>
> Any opinion/advice?
>
> Thank you very much,
> Spamis
>
>