high Traffic setup problem, module status don't deliver data

[Maxim Dounin]

Hello!

On Tue, Feb 11, 2014 at 12:34:59PM +0100, Aleksandar Lazic wrote:

> 
> 
> Am 11-02-2014 12:14, schrieb Valentin V. Bartenev:
> >On Monday 10 February 2014 17:41:47 Aleksandar Lazic wrote:
> 
> [snipp]
> 
> >>Every time when I have more then ~400 r/s we get no data from the
> >>status-request, this request rate means ~20k Packets/Second.
> >>I use netfilter with fail2ban, but not the connection tracking module!
> >
> >Do you see the issue without fail2ban?
> 
> I haven't tried the setup with out.
> 
> >>I have now seen on the tcpdump that I get a 'RST' Package quite
> >>immediately after a request when the 'no answer from server' cames.
> >>
> >>I think this could be a kernel-network issue not a nginx issue.
> >>
> >>The question is:
> >>Please can you help me to find the reason for the immediately  'RST'
> >>answer.
> >>
> >>I hope my question is more clear now.
> >>
> >>Thanks for reading and patience.
> >>
> >
> >You haven't shown your server level configuration.
> >Do you use deferred accept?
> 
> yes
> 
> listen       <IP>:80 deferred default_server;

Try switching it off, there could be a problem if kernel decides 
to switch to syncookies, see this ticket for details:

http://trac.nginx.org/nginx/ticket/353

(The problem is fixed in 1.5.10, and 1.4.5 will have the fix, 
too.)

-- 
Maxim Dounin
http://nginx.org/