tcp keep alive?

[Sebastian Hagedorn]

Have you enabled keepalive in imapd.conf?

tcp_keepalive: 1
-- 
   .:.Sebastian Hagedorn - Weyertal 121 (Gebäude 133), Zimmer 2.02.:.
                .:.Regionales Rechenzentrum (RRZK).:.
  .:.Universität zu Köln / Cologne University - ✆ +49-221-470-89578.:.

Am 16.03.20 um 16:13 schrieb Heiler Bemerguy:
> Hey Guys,
> 
> I have seen this on my Cyrus server 2.5.10, which is preventing new
> users on IMAP:
> 
> root at mailer:~# netstat -na |grep 177.194.176.48 |wc -l
> 27
> root at mailer:~# netstat -na |grep 177.194.176.48
> tcp        0      0 10.1.200.226:143        177.194.176.48:56330   
...
> 
> Not even a single byte is sent to this IP (as seen on tcpdump), and this
> Debian's tcp keepalive is set like:
> 
>     net.ipv4.tcp_keepalive_intvl = 5
>     net.ipv4.tcp_keepalive_probes = 3
>     net.ipv4.tcp_keepalive_time = 60
> 
> And there's an iptables rules like this:
> 
>     iptables -A INPUT -p tcp --syn --dport 143 -m connlimit
>     --connlimit-above 10 --connlimit-mask 32 -j REJECT
>     iptables -A INPUT -p tcp --syn --dport 143 -j ACCEPT
> 
> Even though this user is multiple connected like that for HOURS.......
> 
> -- 
> Best Regards,
> 
> Heiler Bemerguy - CINBESA
> Analista de Redes, Wi-Fi,
> Virtualização e Serviços Internet
> (55) 91 98151-4894
> 
> 
> ----
> Cyrus Home Page: http://www.cyrusimap.org/
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